Radium-223 in women with hormone receptor-positive bone-metastatic breast cancer receiving endocrine therapy: pooled analysis of two international, phase 2, randomized, double-blind, placebo-controlled trials

BACKGROUND

Most women with advanced breast cancer have skeletal metastases. Radium-223 is an alpha-emitting radionuclide that selectively targets areas of bone metastases.

METHODS

Two double-blind, placebo-controlled studies of radium-223 were conducted in women with hormone receptor-positive (HR+), bone-predominant metastatic breast cancer. All patients received endocrine therapy (ET), as a single agent of the investigator's choice (Study A) or exemestane + everolimus (Study B). Patients were randomized to receive radium-223 (55 kBq/kg) or placebo intravenously every 4 weeks for six doses. Accrual was halted following unblinded interim analyses per protocol amendments, and both studies were terminated. We report pooled analyses of symptomatic skeletal event-free survival (SSE-FS; primary endpoint), radiologic progression-free survival (rPFS) and overall survival (OS; secondary), and time to bone alkaline phosphatase (ALP) progression (exploratory).

RESULTS

In total, 382 patients were enrolled, and 196 SSE-FS events (70% planned total) were recorded. Hazard ratios (95% confidence intervals) and nominal p values for radium-223 + ET versus placebo + ET were: SSE-FS 0.809 (0.610-1.072), p = 0.1389; rPFS 0.956 (0.759-1.205), p = 0.7039; OS 0.889 (0.660-1.199), p = 0.4410; and time to bone ALP progression 0.593 (0.379-0.926), p = 0.0195. Radium-223- or placebo-related treatment-emergent adverse events were reported in 50.3% versus 35.1% of patients (grade 3/4: 25.7% vs. 8.5%), with fractures/bone-associated events in 23.5% versus 23.9%.

CONCLUSIONS

In patients with HR+ bone-metastatic breast cancer, numeric differences favoring radium-223 + ET over placebo + ET for the primary SSE-FS endpoint were suggestive of efficacy, in line with the primary outcome measure used in the underlying phase 2 studies. No similar evidence of efficacy was observed for secondary progression or survival endpoints. Adverse events were more frequent with radium-223 + ET versus placebo + ET, but the safety profile of the combination was consistent with the safety profiles of the component drugs. Clinical trial registration numbers Study A: NCT02258464, registered October 7, 2014. Study B: NCT02258451, registered October 7, 2014.

Neoadjuvant anthracycline-based (5-FEC) or anthracycline-free (docetaxel/carboplatin) chemotherapy plus trastuzumab and pertuzmab in HER2 + BC patients according to their TOP2A: a multicentre, open-label, non-randomized phase II trial

PURPOSE

Previous studies have reported the benefit of dual HER2-targeting combined to neoadjuvant chemotherapy in HER2-amplified breast cancer (HER2 + BC). Moreover, besides the cardiac toxicity following their association to Trastuzumab, anthracyclines chemotherapy may not profit all patients. The NeoTOP study was designed to evaluate the complementary action of Trastuzumab and Pertuzumab, and the relevance of an anthracycline-based regimen according to TOP2A amplification status.

METHODS

Open-label, multicentre, phase II study. Eligible patients were aged ≥ 18 with untreated, operable, histologically confirmed HER2 + BC. After centralized review of TOP2A status, TOP2A-amplified (TOP2A+) patients received FEC100 for 3 cycles then 3 cycles of Trastuzumab (8 mg/kg then 6 mg/kg), Pertuzumab (840 mg/kg then 420 mg/kg), and Docetaxel (75mg/m2 then 100mg/m2). TOP2A-not amplified (TOP2A-) patients received 6 cycles of Docetaxel (75mg/m2) and Carboplatin (target AUC 6 mg/ml/min) plus Trastuzumab and Pertuzumab. Primary endpoint was pathological Complete Response (pCR) using Chevallier's classification. Secondary endpoints included pCR (Sataloff), Progression-Free Survival (PFS), Overall Survival (OS), and toxicity.

RESULTS

Out of 74 patients, 41 and 33 were allocated to the TOP2A + and TOP2A- groups respectively. pCR rates (Chevallier) were 74.4% (95%CI: 58.9-85.4) vs. 71.9% (95%CI: 54.6-84.4) in the TOP2A + vs. TOP2A- groups. pCR rates (Sataloff), 5-year PFS and OS were 70.6% (95%CI: 53.8-83.2) vs. 61.5% (95%CI: 42.5-77.6), 82.4% (95%CI: 62.2-93.6) vs. 100% (95%CI: 74.1-100), and 90% (95%CI: 69.8-98.3) vs. 100% (95%CI: 74.1-100). Toxicity profile was consistent with previous reports.

CONCLUSION

Our results showed high pCR rates with Trastuzumab and Pertuzumab associated to chemotherapy. They were similar in TOP2A + and TOP2A- groups and the current role of neoadjuvant anthracycline-based chemotherapy remains questioned.

TRIAL REGISTRATION NUMBER

NCT02339532 (registered on 14/12/14).

p4EBP1 staining predicts outcome in ER-positive endocrine-resistant metastatic breast cancer patients treated with everolimus and exemestane

BACKGROUND

To identify patients most likely to respond to everolimus, a mammalian target of rapamycin (mTOR) inhibitor, a prospective biomarker study was conducted in hormone receptor-positive endocrine-resistant metastatic breast cancer patients treated with exemestane-everolimus therapy.

METHODS

Metastatic tumor biopsies were processed for immunohistochemical staining (p4EBP1, PTEN, pAKT, LKB1, and pS6K). ESR1, PIK3CA and AKT1 gene mutations were detected by NGS. The primary endpoint was the association between the p4EBP1 expression and clinical benefit rate (CBR) at 6 months of everolimus plus exemestane treatment.

RESULTS

Of 150 patients included, 107 were evaluable for the primary endpoint. p4EBP1 staining above the median (Allred score ≥6) was associated with a higher CBR at 6 months (62% versus 40% in high-p4EBP1 versus low-p4EBP1, χ2 test, p = 0.026) and a longer progression-free survival (PFS) (median PFS of 9.2 versus 5.8 months in high-p4EBP1 versus low-p4EBP1; p = 0.02). When tested with other biomarkers, only p4EBP1 remained a significant predictive marker of PFS in multivariate analysis (hazard ratio, 0.591; p = 0.01).

CONCLUSIONS

This study identified a subset of patients with hormone receptor-positive endocrine-resistant metastatic breast cancer and poor outcome who would derive less benefit from everolimus and exemestane. p4EBP1 may be a useful predictive biomarker in routine clinical practice.

CLINICAL TRIAL REGISTRATION

NCT02444390.

European value-based healthcare benchmarking: moving from theory to practice

BACKGROUND

Value-based healthcare (VBHC) is a conceptual framework to improve the value of healthcare by health, care-process and economic outcomes. Benchmarking should provide useful information to identify best practices and therefore a good instrument to improve quality across healthcare organizations. This paper aims to provide a proof-of-concept of the feasibility of an international VBHC benchmarking in breast cancer, with the ultimate aim of being used to share best practices with a data-driven approach among healthcare organizations from different health systems.

METHODS

In the VOICE community-a European healthcare centre cluster intending to address VBHC from theory to practice-information on patient-reported, clinical-related, care-process-related and economic-related outcomes were collected. Patient archetypes were identified using clustering techniques and an indicator set following a modified Delphi was defined. Benchmarking was performed using regression models controlling for patient archetypes and socio-demographic characteristics.

RESULTS

Six hundred and ninety patients from six healthcare centres were included. A set of 50 health, care-process and economic indicators was distilled for benchmarking. Statistically significant differences across sites have been found in most health outcomes, half of the care-process indicators, and all economic indicators, allowing for identifying the best and worst performers.

CONCLUSIONS

To the best of our knowledge, this is the first international experience providing evidence to be used with VBHC benchmarking intention. Differences in indicators across healthcare centres should be used to identify best practices and improve healthcare quality following further research. Applied methods might help to move forward with VBHC benchmarking in other medical conditions.

Intrathecal Catheter for Chemotherapy in Leptomeningeal Carcinomatosis From HER2-Negative Metastatic Breast Cancer

PURPOSE

Most oncological treatments for leptomeningeal metastasis (LM) do not cross the blood-brain barrier (BBB). One therapeutic option is intrathecal (IT) chemotherapy. Both the brain-implanted Omaya reservoir and lumbar puncture (LP) are classic routes for IT chemotherapy delivery. An intrathecal catheter (IC) connected to a subcutaneous port is a recently developed option for the management of chemotherapy infusions. It is essential to evaluate the efficacy and safety of chemotherapy infusion using such device.

METHODS

We conducted a retrospective monocentric study within Institut de cancerologie de l'Ouest at Angers, including all patients with advanced breast cancer (aBC) with LM implanted with an IT device for IT chemotherapy between January 2013 and May 2020. The primary endpoint was overall survival (OS) and secondary endpoints included surgical feasibility, patient safety, and progression-free survival (PFS). The catheter was inserted through an LP, the tip was positioned at the right level and connected to a subcutaneous port implanted under the skin of the anterior thoracic wall. IT chemotherapy is painless and easy for qualified nurses to administer on an outpatient basis.

RESULTS

Thirty women underwent the implantation. No failures occurred during the procedure. A total of 77% of patients reported no complications after implantation. Only three complications required surgical treatment. The median number of IT chemotherapy courses per patient was 8 (range, 2-27). The tolerance profile for iterative IT chemotherapy was manageable in ambulatory care. With a median follow-up of 76.5 months (95% confidence interval [CI], 11.6-not available), the median OS was 158 days (95% CI, 87-235), and the median PFS was 116 days (95% CI, 58-174).

CONCLUSION

Infusing chemotherapy using an implanted catheter is an efficient option for managing IT chemotherapy with a good tolerance profile. Patient-reported outcomes for the evaluation of IT chemotherapy toxicity are currently being developed.

AMEERA-4: a randomized, preoperative window-of-opportunity study of amcenestrant versus letrozole in early breast cancer

BACKGROUND

Window-of-opportunity (WOO) studies provide insights into the clinical activity of new drugs in breast cancer.

METHODS

AMEERA-4 (NCT04191382) was a WOO study undertaken to compare the pharmacodynamic effects of amcenestrant, a selective estrogen receptor degrader, with those of letrozole in postmenopausal women with newly diagnosed, operable estrogen receptor-positive, human epidermal growth factor receptor 2-negative (ER+/HER2-) breast cancer. Women were randomized (1:1:1) to receive amcenestrant 400 mg, amcenestrant 200 mg, or letrozole 2.5 mg once daily for 14 days before breast surgery. The primary endpoint was change in Ki67 between baseline and Day 15 (i.e., day of surgery).

RESULTS

Enrollment was stopped early because of slow recruitment, in the context of the COVID-19 pandemic. The modified intent-to-treat population consisted of 95 study participants with baseline and post-treatment Ki67 values, whereas the safety population included 104 participants who had received at least one dose of study medication. Relative change from baseline in Ki67 was - 75.9% (95% confidence interval [CI] - 81.9 to - 67.9) for amcenestrant 400 mg, - 68.2% (- 75.7 to - 58.4) for amcenestrant 200 mg, and - 77.7% (- 83.4 to - 70.0) for letrozole (geometric least-squares mean [LSM] estimates). Absolute change in ER H-score from baseline (LSM estimate) was - 176.7 in the amcenestrant 400 mg arm, - 202.9 in the amcenestrant 200 mg arm, and - 32.5 in the letrozole arm. There were no Grade ≥ 3 treatment-related adverse events.

CONCLUSIONS

Both amcenestrant and letrozole demonstrated antiproliferative activity in postmenopausal women with previously untreated, operable ER+/HER2- breast cancer and had good overall tolerability.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT04191382 https://clinicaltrials.gov/ct2/show/NCT04191382 . Registered 9 December 2019.

Landscape of baseline and acquired genomic alterations in circulating tumor DNA with abemaciclib alone or with endocrine therapy in advanced breast cancer

PURPOSE

To identify potential predictors of response and resistance mechanisms in patients with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) advanced breast cancer (ABC) treated with the CDK4/6 inhibitor abemaciclib +/- endocrine therapy (ET), baseline and acquired genomic alterations in circulating tumor DNA (ctDNA) were analyzed and associated with clinical outcomes.

PATIENTS AND METHODS

MONARCH 3: postmenopausal women with HR+, HER2- ABC and no prior systemic therapy in the advanced setting were randomized to abemaciclib or placebo plus nonsteroidal aromatase inhibitor (NSAI). nextMONARCH: women with HR+, HER2- metastatic breast cancer that progressed on/after prior ET and chemotherapy were randomized to abemaciclib alone (two doses) or plus tamoxifen. Baseline and end-of-treatment plasma samples from patients in MONARCH 3 and nextMONARCH (monotherapy arms) were analyzed to identify somatic genomic alterations. Association between genomic alterations and median progression-free survival (mPFS) was assessed.

RESULTS

Most patients had ≥1 genomic alteration detected in baseline ctDNA. In MONARCH 3, abemaciclib+NSAI was associated with improved mPFS versus placebo+NSAI, regardless of baseline alterations. ESR1 alterations were less frequently acquired in the abemaciclib+NSAI arm than placebo+NSAI. Acquired alterations potentially associated with resistance to abemaciclib +/- NSAI included RB1 and MYC.

CONCLUSIONS

In MONARCH 3, certain baseline ctDNA genomic alterations were prognostic for ET but not predictive of abemaciclib response. Further studies are warranted to assess whether ctDNA alterations acquired during abemaciclib treatment differ from other CDK4/6 inhibitors. Findings are hypothesis-generating, further exploration is warranted into mechanisms of resistance to abemaciclib and ET.

Prognostic Markers of DNA Methylation and Next-Generation Sequencing in Progressive Glioblastoma from the EORTC-26101 Trial

PURPOSE

The EORTC-26101 study was a randomized phase II and III clinical trial of bevacizumab in combination with lomustine versus lomustine alone in progressive glioblastoma. Other than for progression-free survival (PFS), there was no benefit from addition of bevacizumab for overall survival (OS). However, molecular data allow for the rare opportunity to assess prognostic biomarkers from primary surgery for their impact in progressive glioblastoma.

EXPERIMENTAL DESIGN

We analyzed DNA methylation array data and panel sequencing from 170 genes of 380 tumor samples of the EORTC-26101 study. These patients were comparable with the overall study cohort in regard to baseline characteristics, study treatment, and survival.

RESULTS

Of patients' samples, 295/380 (78%) were classified into one of the main glioblastoma groups, receptor tyrosine kinase (RTK)1, RTK2 and mesenchymal. There were 10 patients (2.6%) with isocitrate dehydrogenase mutant tumors in the biomarker cohort. Patients with RTK1 and RTK2 classified tumors had lower median OS compared with mesenchymal (7.6 vs. 9.2 vs. 10.5 months). O6-methylguanine DNA-methyltransferase (MGMT) promoter methylation was prognostic for PFS and OS. Neurofibromin (NF)1 mutations were predictive of response to bevacizumab treatment.

CONCLUSIONS

Thorough molecular classification is important for brain tumor clinical trial inclusion and evaluation. MGMT promoter methylation and RTK1 classifier assignment were prognostic in progressive glioblastoma. NF1 mutation may be a predictive biomarker for bevacizumab treatment.

COVID-19 Infection despite Previous Vaccination in Cancer Patients and Healthcare Workers: Results from a French Prospective Multicenter Cohort (PAPESCO-19)

In a multicenter prospective cohort of cancer patients (CP; n = 840) and healthcare workers (HCWs; n = 935) vaccinated against COVID-19, we noticed the following: i/after vaccination, 4.4% of HCWs and 5.8% of CP were infected; ii/no characteristic was associated with post-vaccine COVID-19 infections among HCWs; iii/CP who developed infections were younger, more frequently women (NS), more frequently had gastrointestinal, gynecological, or breast cancer and a localized cancer stage; iv/CP vaccinated while receiving chemotherapy or targeted therapy had (NS) more breakthrough infections after vaccination than those vaccinated after these treatments; the opposite was noted with radiotherapy, immunotherapy, or hormonotherapy; v/most COVID-19 infections occurred either during the Alpha wave (11/41 HCW, 20/49 CP), early after the first vaccination campaign started, or during the Omicron wave (21/41 HCW, 20/49 CP), more than 3 months after the second dose; vi/risk of infection was not associated with values of antibody titers; vii/the outcome of these COVID-19 infections after vaccination was not severe in all cases. To conclude, around 5% of our CPs or HCWs developed a COVID-19 infection despite previous vaccination. The outcome of these infections was not severe.

Adjuvant endocrine therapy uptake, toxicity, quality of life, and prediction of early discontinuation

BACKGROUND

Many patients receiving adjuvant endocrine therapy (ET) for breast cancer experience side effects and reduced quality of life (QoL) and discontinue ET. We sought to describe these issues and develop a prediction model of early discontinuation of ET.

METHODS

Among patients with hormone receptor-positive and HER2-negative stage I-III breast cancer of the Cancer Toxicities cohort (NCT01993498) who were prescribed adjuvant ET between 2012 and 2017, upon stratification by menopausal status, we evaluated adjuvant ET patterns including treatment change and patient-reported discontinuation and ET-associated toxicities and impact on QoL. Independent variables included clinical and demographic features, toxicities, and patient-reported outcomes. A machine-learning model to predict time to early discontinuation was trained and evaluated on a held-out validation set.

RESULTS

Patient-reported discontinuation rate of the first prescribed ET at 4 years was 30% and 35% in 4122 postmenopausal and 2087 premenopausal patients, respectively. Switching to a new ET was associated with higher symptom burden, poorer QoL, and higher discontinuation rate. Early discontinuation rate of adjuvant ET before treatment completion was 13% in postmenopausal and 15% in premenopausal patients. The early discontinuation model obtained a C index of 0.62 in the held-out validation set. Many aspects of QoL, most importantly fatigue and insomnia (European Organization for Research and Treatment of Cancer QoL questionnaire 30), were associated with early discontinuation.

CONCLUSION

Tolerability and adherence to ET remains a challenge for patients who switch to a second ET. An early discontinuation model using patient-reported outcomes identifies patients likely to discontinue their adjuvant ET. Improved management of toxicities and novel more tolerable adjuvant ETs are needed for maintaining patients on treatment.

AMEERA-3: Randomized Phase II Study of Amcenestrant (Oral Selective Estrogen Receptor Degrader) Versus Standard Endocrine Monotherapy in Estrogen Receptor-Positive, Human Epidermal Growth Factor Receptor 2-Negative Advanced Breast Cancer

PURPOSE

Amcenestrant (oral selective estrogen receptor degrader) demonstrated promising safety and efficacy in earlier clinical studies for endocrine-resistant, estrogen receptor-positive/human epidermal growth factor receptor 2-negative (ER+/HER2-) advanced breast cancer (aBC).

PATIENTS AND METHODS

In AMEERA-3 (ClinicalTrials.gov identifier: NCT04059484), an open-label, worldwide phase II trial, patients with ER+/HER2- aBC who progressed in the (neo)adjuvant or advanced settings after not more than two previous lines of endocrine therapy (ET) were randomly assigned 1:1 to amcenestrant or single-agent endocrine treatment of physician's choice (TPC), stratified by the presence/absence of visceral metastases, previous/no treatment with cyclin-dependent kinase 4/6 inhibitor, and Eastern Cooperative Oncology Group performance status (0/1). The primary end point was progression-free survival (PFS) by independent central review, compared using a stratified log-rank test (one-sided type I error rate of 2.5%).

RESULTS

Between October 22, 2019, and February 15, 2021, 290 patients were randomly assigned to amcenestrant (n = 143) or TPC (n = 147). PFS was numerically similar between amcenestrant and TPC (median PFS [mPFS], 3.6 v 3.7 months; stratified hazard ratio [HR], 1.051 [95% CI, 0.789 to 1.4]; one-sided P = .643). Among patients with baseline mutated ESR1; (n = 120 of 280), amcenestrant numerically prolonged PFS versus TPC (mPFS, 3.7 v 2.0 months; stratified HR, 0.9 [95% CI, 0.565 to 1.435]). Overall survival data were immature but numerically similar between groups (HR, 0.913; 95% CI, 0.595 to 1.403). In amcenestrant versus TPC groups, treatment-emergent adverse events (any grade) occurred in 82.5% versus 76.2% of patients and grade ≥3 events occurred in 21.7% versus 15.6%.

CONCLUSION

AMEERA-3 did not meet its primary objective of improved PFS with amcenestrant versus TPC although a numerical improvement in PFS was observed in patients with baseline ESR1 mutation. Efficacy and safety with amcenestrant were consistent with the standard of care for second-/third-line ET for ER+/HER2- aBC.

Evaluating everolimus for the treatment of breast cancer

INTRODUCTION

Everolimus is an oral drug that inhibits mTOR with immunosuppressive and antiproliferative characteristics. It is commonly used in association with exemestane in hormone receptor (HR)-positive advanced breast cancer (ABC).

AREAS COVERED

The current review summarizes the publications relating to everolimus from clinical research in breast cancer. Everolimus showed treatment efficacy and an acceptable safety tolerance with prevention of side effects in Phase II/III studies. BOLERO-2 study showed a progression-free survival improvement in patients with HR-positive ABC previously treated with aromatase inhibitors (AI) and leading to its acceptance in this indication. The absence of a post CDK4/6 inhibitor (CDK4/6i.) study and the arrival of new drugs may raise questions about its current place in the therapeutic strategy.

EXPERT OPINION

Everolimus is relevant in the management of HR-positive ABC. Because of its efficacy, acceptable tolerability and the absence of drugs that have shown a greater benefit, it remains a second-line treatment option in HR-positive, HER2 negative (score 0) patients without BRCA mutation or visceral crisis and can be discuss with fulvestrant in second line after CDK4-6i. It is likely that within 5 years this treatment will be replaced in second line HR-positive breast cancer by new emerging treatments: drug-conjugated antibodies, tyrosine kinase inhibitors or immunotherapy in combination with chemotherapy.

Abstract 4926: Alpelisib in combination with trastuzumab and pertuzumab as maintenance therapy in patients with HER2+, PIK3CA-mutant advanced breast cancer: EPIK-B2 Study Part 1 safety and efficacy results

Introduction: Current standard first-line (1L) treatment (tx) for patients (pts) with human epidermal growth factor receptor 2 (HER2)-positive advanced breast cancer (ABC) includes taxanes plus trastuzumab (T) and pertuzumab (P). Mutations (mut) in phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) gene encoding PI3Kα have been reported in 12%-39% of HER2+ BCs and associated with worse prognoses and lower pathological complete response to anti-HER2 tx in the neoadjuvant setting. Alpelisib (ALP) is an oral, α-specific PI3K inhibitor approved at 300 mg per day (QD) in combination with fulvestrant in hormone receptor (HR)-positive, HER2−, PIK3CA-mut ABC following progression on/after endocrine therapy. EPIK-B2 is a 2-part Phase 3 study to evaluate ALP plus T+P as 1L maintenance tx in pts with HER2+, PIK3CA-mut ABC, without progressive disease at study entry. Here, we report results of Part 1, the safety run-in of EPIK-B2.

Methods: Part 1 of EPIK-B2 was open label and assessed safety of ALP plus T+P in pts with HER2+ ABC and confirmed the recommended Phase 3 dose of ALP for the randomized Part 2. Pts with HER2+ ABC, with or without a PIK3CA mut, who had completed induction taxane chemotherapy plus T+P were eligible for Part 1. Part 2, currently enrolling, allows only PIK3CA-mut pts. Pts in Part 1 received 300 mg (Cohort A) or 250 mg (Cohort B) ALP QD plus 6 mg/kg T and 420 mg P, on Day 1 of each 21-day cycle. The primary endpoint of Part 1 was incidence of dose-limiting toxicities (DLTs) in the first 6 wk of tx; secondary endpoints included safety/tolerability and ALP exposure by dose level. Preliminary confirmed overall response rate (ORR; best overall response [BOR] of CR/PR) and clinical benefit rate (CBR; BOR of CR/PR/SD lasting ≥24 wk) were evaluated per RECIST v1.1 during the on-treatment period.

Results: Three pts in Cohort A and 12 in Cohort B received 300 mg and 250 mg ALP, respectively. DLTs, 1 event each of hyperglycemia and dermatitis acneiform, were seen in Cohort A, none were reported in Cohort B pts given 250 mg ALP; however, Part 2 of EPIK-B2 will be initiated with 200 mg ALP with the option of intrapatient dose escalation to 250 mg QD, the maximum tolerated dose, per FDA feedback to consider a lower toxicity threshold in 1L maintenance setting. No unexpected AEs were reported; most common AEs were diarrhea, decreased appetite, and hyperglycemia. Six of 15 pts (40%; 2 in Cohort A, 4 in Cohort B) had PIK3CA-mut disease. Among these, ORR was 50% (n/N=3/6) and CBR was 100% (n/N=6/6). Tumor response was maintained in 5 of 6 pts with PIK3CA mutations (83%) after ≥21 cycles of tx (range, 21-31).

Conclusions: ALP plus T+P combination is safe; reported AEs align with those in previous ALP studies. Preliminary efficacy data suggest promising clinical benefit with ALP plus T+P for pts with HER2+ PIK3CA-mut disease.

Citation Format: Sara A. Hurvitz, François-Clement Bidard, Wei Li, Xichun Hu, Sonia Pernas, Joseph Thaddeus Beck, Mario Campone, Kevin Punie, Michelle Miller, Mathilde Kaper, Yu Han, Farhat Ghaznawi, Guy Jerusalem. Alpelisib in combination with trastuzumab and pertuzumab as maintenance therapy in patients with HER2+, PIK3CA-mutant advanced breast cancer: EPIK-B2 Study Part 1 safety and efficacy results. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4926.

Pattern and risk factors of isolated local relapse among women with hormone receptor-positive and HER2-negative breast cancer and lymph node involvement: 10-year follow-up analysis of the PACS 01 and PACS 04 trials

PURPOSE

We aimed to determine the pattern of isolated local recurrences (ILR) in women with stage II-III hormone receptor-positive and human epidermal growth factor receptor 2 breast cancer (HR + /HER2-BC) after 10-year follow-up.

METHODS

UNICANCER-PACS 01 and PACS 04 trials included 5,008 women with T1-T3 and N1-N3 to evaluate the efficacy of different anthracycline ± taxanes-containing regimens after modified mastectomy or lumpectomy plus axillary lymph node dissection. We analyzed the data from 2,932 women with HR + /HER2- BC to evaluate the cumulative incidence of ILR and describe the factors associated with ILR.

RESULTS

After a median follow-up of 9.1 years (95% CI 9.0-9.2 years), the cumulative incidence of ILR increased steadily between 1 and 10 years from 0.2% to 2.5%. The multivariable analysis showed that older age (subhazard ratios [sHR] = 0.95, 95% CI 0.92-0.99) and mastectomy (sHR = 0.39, 95% CI 0.17-0.86) were associated with lower risk of ILR, and no adjuvant endocrine therapy (sHR = 2.73, 95% CI 1.32 7-5.67) with increased risk of ILR.

CONCLUSION

In this population of high-risk patients with localized HR + /HER2- BC, the risk of ILR was low but remained constant over 10 years. Younger age at diagnosis, breast-conserving surgery, and adjuvant endocrine therapy were independent risk factors of ILR.

Abstract P3-11-09: Extracellular vesicle-based biomarker assay for the monitoring of the efficacy of frontline endocrine therapy + CDK4-6 inhibitors in metastatic breast cancer

CONTEXT: Endocrine therapy combined with CDK4/6 inhibitor is the standard frontline treatment for the vast majority of HR+/HER2- metastatic breast cancer (MBC) patients. Despite an overall survival benefit, patients eventually progress and mechanisms of resistance to this combination are not well identified. Non-invasive monitoring of the efficacy of treatment could help into tailoring therapeutic regimen. Extracellular vesicles (EVs) are a group of heterogeneous nanosized bioparticles (30-1000nm), released by almost all cell types - including tumor, platelets, and immune cells – carrying informative biological material emanating from the mother cell and circulating in the blood stream. In this project, we ambition to assess whether the vesiclemia, i.e. plasmatic extracellular vesicle concentration can be used as a clinic-biological parameter to assist in the monitoring of patients. METHODS: EPICURE is an ongoing pilot prospective cohort study of heterogeneous and massive data integration, i.e. multi-omics approaches in MBC patients. The present study focused on patients with HR+/HER2- MBC receiving frontline endocrine therapy+iCDK4/6. Plasma samples were drawn every 3 months during the treatment until progression. The workflow for the enrichment of circulating EVs was developed from frozen plasma. A semi-automatized isolation procedure using size exclusion chromatography combined with the newly developed interference light microscopy apparatus Videodrop allowed to routinely separate plasmatic EVs and quantify vesiclemia in a fast and reliable manner for a large number of samples (longitudinal follow-up of MBC patients). RESULTS: 26 patients were included and monitored for vesiclemia. Median age was 58.5y (±13.7). Metastatic disease sites were distributed as follows: bone metastases (21; 84%), liver (21; 84%), thoracic (10; 40%), node (2; 8%), brain (1; 4%), others (2; 8%). Endocrine therapy included aromatase inhibitors (20; 77%), fulvestrant (6; 29%), GnRH agonists (5; 19%) and CDK4/6 inhibitors palbocilib (15; 57%), abemaciclib (8; 31%) and ribociclib (3; 11%). With a median follow-up time of 22.1 months (95%CI 21.2 - not reached), median progression free survival was 21.8 months (95%CI 18.1 - not reached). Median time on treatment was 19.4 months (IQR 11.6 - 22.1). Objective response rate was confirmed in 12 patients (6 with complete response). Out of the 26 patients, 12 stopped the frontline treatment due to disease progression. 135 longitudinal follow-up samples were analyzed for EVs. All patients who progressed rapidly after treatment initiation (i.e median PFS< 6 months) had an increased vesiclemia at the months 2 and 6 after inclusion. Conversely, patients who had a median PFS >18m had a stable vesiclemia during this period. CONCLUSION This study aims to use circulating EVs as a therapeutic companion to anticipate treatment resistance and tumor progression in MBC patients. Our preliminary data suggest that the vesiclemia could be used as a predictive tool to anticipate treatment failure, and thus might be used to tailor treatments in time.

Citation Format: Mathilde Richard, Jean Sebastien FRENEL, Laurent Mathiot, Mario Campone, Mathilde Colombie, Marie Robert, Anne Patsouris, Frederic Bigot, Julie Gavard, Gwennan André-Grégoire, Laetitia Guevel. Extracellular vesicle-based biomarker assay for the monitoring of the efficacy of frontline endocrine therapy + CDK4-6 inhibitors in metastatic breast cancer. [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P3-11-09.

Abstract P5-02-37: Multi-omics approach to identify markers of resistance to endocrine therapy + CDK4/6 inhibitors in first line HR+/HER2- metastatic breast cancer (MBC) patients

CONTEXT: Endocrine therapy combined with CDK4/6 inhibitor is the standard frontline treatment for the vast majority of HR+/HER2- MBC patients. Despite an overall survival benefit, patients eventually progress and mechanisms of resistance to this combination are not well identified. METHODS: EPICURE is an ongoing pilot prospective cohort study of heterogeneous and massive data integration, ie. multi-omics approach in MBC patients. The present study aims at identifying progression markers in patients with HR+/HER2- MBC receiving frontline endocrine therapy+iCDK4/6 by means of transcriptomics, genomics and proteomics data. All patients had a tumor biopsy at the entry in the study (B1) and a biopsy was repeated at progression if feasible (B2). Transcriptomic (RNAseq: NextSeq550, Illumina), genomic (whole exome sequencing: NextSeq550, Illumina) and proteomic (DIA mass spectrometry: TimsTOFPro2, Bruker) were performed on B1 and B2 according to available tumor tissue. RESULTS: Fifty-one patients matching inclusion criteria were included. B1 was done at inclusion for all patients (B1) (n = 51) and B2 was performed in 8 patients. (B2) (n = 8). Eight metastatic sites were biopsied: node (n = 17); liver (n = 16); bone (n = 8); breast local recurrence (n = 5); chest wall (n = 5); skin (n = 4); pleural (n = 3); ovary (n = 1). Transcriptomic, genomic and proteomic analysis of paired biopsies (B1 and B2) was performed in parallel and separately for 8, 7 and 2 patients, respectively. Exploratory data analysis of transcriptomic and proteomic data showed that liver biopsies clustered together. In order to eliminate this anatomic bias, specific genes and proteins of liver metastases were identified by means of DESeq2 analysis (12 liver vs 39 other sites) for transcriptomic data (n = 2654) and LIMMA (4 liver vs 14 other sites) for proteomic data (n = 227), and excluded for the rest of the analysis. Differential analyses (ie. gene expression, non-synonymous mutations and protein expression) between B1 and B2 were performed for each patient. These three kind of lists were finally submitted to ToppGene, DAVID and GOrilla for Gene Ontology terms enrichment analyses. Transcriptomic analyses of the 8 paired biopsies highlighted immune response (IR) in seven B1, IR in four B2 and neurogenesis in three B2. Genomics data evaluation between B1 and B2 pointed out “transposon integration” as an important pathway. Proteomic data of the 2 paired biopsies analysed underlined high immune response in B1, and muscle development/contraction and response to tumor necrosis factor in B2 for one patient. For the second one, liver metabolism in B1 and extracellular matrix and p38 MAPK cascade were emphasised. CONCLUSION: This preliminary study based on transcriptomic, genomic and proteomic data represents an encouraging first step of the EPICURE project. In a near future, additional paired biopsies and other kinds of omics data (epigenetics, radiomics, microbiomics, exposomics) will be available. Furthermore, omics data will be analysed in an integrated manner (ie. artificial intelligence), which will make it possible to detect synergies across the different omics data.

Citation Format: Jean Sebastien FRENEL, Fadoua Ben Azzouz, Frederic Bigot, Jonathan Dauve, Marie Francoise Heymann, Wilfried Gouraud, Catherine Guette, Hamza Lasla, Bertrand Michel, Alain Morel, Anne Patsouris, Marie Robert, Grégoire Siekaniec, Mathilde Colombie, Pascal Jézéquel, Mario Campone. Multi-omics approach to identify markers of resistance to endocrine therapy + CDK4/6 inhibitors in first line HR+/HER2- metastatic breast cancer (MBC) patients. [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P5-02-37.

Abstract P5-02-32: Differential Gene Mutation Landscape in Patients With PIK3CA-altered and Non-altered Hormone Receptor-Positive, Human Epidermal Growth Factor Receptor 2-negative Advanced Breast Cancer in the SOLAR-1 Clinical Study

Introduction: The phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit alpha (PIK3CA) is found mutated (mut) in ~40% of patients (pts) with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2−) advanced breast cancer (ABC); some of these alterations can lead to PI3K pathway hyperactivation and are associated with endocrine resistance and poor prognosis in advanced disease. Alpelisib (ALP), an α-selective PI3K inhibitor and degrader, demonstrated clinical benefit in combination with fulvestrant (FUL) in the SOLAR-1 study in pts with PIK3CA-mut HR+, HER2− ABC. SOLAR-1 (NCT02437318) was a double-blind, placebo (PBO)-controlled, stratified, randomized (per PIK3CA-alt status as determined by QIAGEN PIK3CA RGQ PCR test), Phase III study of ALP in combination with FUL in pts with HR+, HER2− ABC who progressed on/after aromatase inhibitor therapy. Here, we compare the gene alteration landscape in pts with altered (alt) and non-alt PIK3CA and the efficacy of ALP + FUL in pts whose tumors have alterations in both selected genes or cell signaling pathways as well as PIK3CA-alt or non-alt status as determined by next-generation sequencing (NGS).

Methods: In this analysis, retrospective NGS analysis using the FoundationOne CDx 324-gene panel was performed on available FFPE tissue samples. In all, 398 pts were categorized into 2 cohorts based on NGS-tested PIK3CA status. The PIK3CA-alt cohort comprised 237 patients (ALP, n=120; PBO, n=117); the PIK3CA-non-alt cohort 161 patients (ALP, n=81; PBO, n=80). Selected genes altered in >20 SOLAR-1 pts were investigated further. Clinical benefit was assessed by progression-free survival (PFS) based on gene alt status in the PIK3CA-alt and -non-alt cohorts. Hazard ratios (HR) for PFS were estimated using a multivariate Cox PH model by adjusting multiple clinical covariates including age, ECOG performance status, bone lesion, prior CDK4/6 inhibitor treatment, and lung/liver metastasis.

Results: PIK3CA-alt and -non-alt cohorts had differential genomic landscapes; differential PFS benefit was observed among the genes analyzed, including ARID1A, EMSY, FGFR2, MAP3K1, MYC, RAD21, RAD51C, TP53, and a gene set associated with the MAPK pathway. In most pts with analyzed gene alterations, numerically longer PFS was observed with ALP vs PBO in the PIK3CA-alt cohort than the -non-alt cohort, particularly pts with alterations in ARID1A (median [m] PFS for ALP vs PBO in PIK3CA-alt cohort: 22.11 vs 12.42 mo, HR 0.48; vs mPFS in PIK3CA-non-alt cohort: 6.21 vs 22.31 mo, HR 1.33) and MAP3K1 (PIK3CA-alt cohort: 17.25 vs 7.70 mo, HR 0.50; vs PIK3CA-non-alt cohort: 9.17 vs 5.26 mo, HR 1.32). Full results are found in the Table. Results should be interpreted with caution, as analyses used small sample sizes and were not adjusted for multiple testing.

Conclusions: A differential genomic landscape was observed in PIK3CA-alt and PIK3CA-non-alt populations. Clinical benefit of ALP vs PBO was observed in pts with PIK3CA-alt disease who also had alterations in analyzed genes and/or genes associated with the MAPK pathway. The data from this analysis suggest that, of the genes analyzed, only PIK3CA mutations can predict pt sensitivity to ALP.

Table. PFS in PIK3CA-altered PIK3CA-non-altered populations by gene alteration

Citation Format: Dejan Juric, Hope Rugo, Albert Reising, Chong Ma, Eva Ciruelos, Sibylle Loibl, Christian F. Singer, Joo Hyuk Sohn, Mario Campone, PierFranco Conte, Hiroji Iwata, Farhat Ghaznawi, Michelle Miller, Tetiana Taran, Faye Su, Fabrice Andre. Differential Gene Mutation Landscape in Patients With PIK3CA-altered and Non-altered Hormone Receptor-Positive, Human Epidermal Growth Factor Receptor 2-negative Advanced Breast Cancer in the SOLAR-1 Clinical Study [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P5-02-32.

Abstract GS1-09: Abemaciclib plus endocrine therapy for HR+, HER2-, node-positive, high-risk early breast cancer: results from a pre-planned monarchE overall survival interim analysis, including 4-year efficacy outcomes

Background Adjuvant abemaciclib (a CDK4 and 6 inhibitor) combined with ET resulted in significant and clinically meaningful improvement in invasive disease-free survival (IDFS) and distant relapse-free survival (DRFS) in patients (pts) with HR+, HER2-, node-positive, high risk EBC in the monarchE trial, and is an approved adjuvant therapy for these patients. Here we present efficacy results from a pre-specified overall survival interim analysis (OS IA2) which was planned to occur 2 years (yrs) after the primary outcome analysis. Methods Pts were randomized (1:1) to receive ET for up to 10 yrs +/- abemaciclib for 2 yrs (study treatment period). High-risk EBC was defined as either ≥4 positive axillary lymph nodes (ALN), or 1-3 ALN with either Grade 3 disease and/or tumor ≥5 cm (Cohort 1). While the proliferation biomarker Ki-67 was centrally assessed in all pts with available tissue sample, an additional smaller group of pts with 1-3+ ALN and central Ki-67 ≥20% as the only high-risk feature were included (Cohort 2). The intent-to-treat (ITT) population consisted of both Cohort 1 (5120 pts) and Cohort 2 (517 pts). Hazard ratios (HR) were estimated using Cox proportional hazard model. Results At a median follow-up of 42 months, all pts were off abemaciclib. IDFS and DRFS data illustrate a sustained benefit beyond the treatment period. In the ITT population, the HR for IDFS was 0.664 (95% CI: 0.578, 0.762) and DRFS was 0.659 (95% CI: 0.567, 0.767). At 4 yrs, this reflected an improvement in IDFS rates from 79.4% to 85.8% (absolute difference 6.4%), and in DRFS rates from 82.5% to 88.4% (absolute difference 5.9%). The continued separation of the curves was associated with an increase in absolute benefit in IDFS 4-year rates compared to 2-and 3-year IDFS rates (absolute difference 2.8% and 4.8% respectively). While OS remained immature, there was a lower number of deaths observed in the abemaciclib plus ET arm compared to the ET alone arm (157 [5.6%] vs 173 [6.1%], HR 0.929 [95% CI: 0.748, 1.153], p = 0.503), suggesting that the robust benefit in IDFS and DRFS began to translate into a numerically favorable OS HR. As previously described, within Cohort 1, a Ki-67 index of ≥20% was associated with a worse prognosis, but similar abemaciclib treatment effects were observed regardless of Ki-67 index. No new safety signals were observed. Conclusion The clinically meaningful benefit of adjuvant abemaciclib added to ET in HR+, HER2-, node-positive, high-risk EBC persists beyond completion of abemaciclib therapy, yielding an increase in absolute IDFS and DRFS benefit at 4 yrs. While OS remains immature at this time, the lower number of deaths in the abemaciclib arm compared to the ET arm suggest that a survival signal favoring abemaciclib is emerging.

Citation Format: Stephen Johnston, Masakazu Toi, Joyce O’Shaughnessy, Priya Rastogi, Mario Campone, Patrick Neven, Chiun Sheng Huang, Jens Huober, Georgina Garnica Jaliffe, Irfan Cicin, Sara Tolaney, Matthew P. Goetz, Hope Rugo, Elżbieta Senkus, Laura Testa, Lucia Del Mastro, Chikako Shimizu, Ran Wei, Ashwin Shahir, Maria Munoz, Belen San Antonio, Valerie Andre, Nadia Harbeck, Miguel Martín. Abemaciclib plus endocrine therapy for HR+, HER2-, node-positive, high-risk early breast cancer: results from a pre-planned monarchE overall survival interim analysis, including 4-year efficacy outcomes [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr GS1-09.

Abstract P2-02-07: Patients’ selection of daily timing of oral intake of adjuvant hormonotherapy (HT) and everolimus (EVE) for high risk early breast cancer in the UCBG-UNIRAD phase III trial

Background: Everolimus (EVE) addition to adjuvant hormonotherapy (HT) for high-risk early breast cancer (BC) did not improve 3-year disease-free survival (DFS) compared with ET alone in the randomized UNIRAD trial (NCT01805271) (1). Most patients (pts) withdrew from EVE for adverse events nearly midway before the expected treatment duration of 2 years. The main EVE target involves m-TOR-induced S6 protein phosphorylation, which is controlled by the molecular circadian clock in mice and cells. Toward the analysis of possible circadian time-dependencies in EVE toxicities and efficacy, we first determine the actual distribution of the daily times chosen by the patients for both oral EVE and HT intakes.

Patients and methods: The registered pts were asked to record the clock hours they chose for both HT and EVE or placebo (PLAC) intakes within four possible daily 6-h slots, i.e. from 06:00 to 11:59 (morning), 12:00 to 17:59 (midtime), 18:00 to 23:59 (evening), or 24:00 to 05:59, (night) in a daily diary throughout their participation in the trial. Modifications in times of drugs intake were reported. Comparisons between groups involved Kruskal-Wallis sum test and Pearson’s Chi-squared and Fisher’s exact tests.

Results: Out of 1,278 randomized patients, 1063 (83,1 %) recorded the times of EVE or PLAC intakes, 852 recorded those for HT intakes. Only 10 pts reported night EVE/PLAC intakes and were not considered here. Of the 1053 evaluated pts; 549 pts took EVE/PLAC in the morning, 82 pts at midtime and 422 in the evening. As compared with evening intakes, morning or midtime intakes of EVE or PLAC were significantly associated with an older age, and post-menopausal status, whilst younger and premenopausal women preferentially chose evening intakes (p< 0.001 for both). Consistently, HT with aromatase inhibitors (AI) were mostly taken in the morning or at midtime, whereas tamoxifene (TAM) was mostly taken the evening (p = 0.001). Tumor size, lymph nodes involvement, histological grade, hormonal receptors status, and EVE initial dose were similarly distributed among the three time slots (Table 1). A similar distribution of oral intake times as in the whole timing study population was found according to age, menopausal status and HT type in the EVE arm (N=508 pts), and in the HT population (+/- EVE or PLAC) (N=852 pts). Initial oral timing intake was modified for EVE by 50 of 508 pts (10%) and for HT by 10 of 852 pts (1%).

Conclusion: To the best of our knowledge, it is the first time that the patients’ spontaneous selection of daily times for oral intakes of a targeted agent (EVE) and HT is reported in a large series of early breast cancer pts. Age and menopausal status were important determinants of patient-selected daily timing intakes of both EVE and HT, as well as HT types. These findings will be carefully considered in the analyses of possible EVE and HT timing effects on adverse events and efficacy of the current adjuvant regimens.

1) Bachelot T et al, J Clin Oncol. 2022 May 23

Opportunities and Obstacles to the Development of Health Data Warehouses in Hospitals in France: The Recent Experience of Comprehensive Cancer Centers

Big Data and Artificial Intelligence can profoundly transform medical practices, particularly in oncology. Comprehensive Cancer Centers have a major role to play in this revolution. With the purpose of advancing our knowledge and accelerating cancer research, it is urgent to make this pool of data usable through the development of robust and effective data warehouses. Through the recent experience of Comprehensive Cancer Centers in France, this article shows that, while the use of hospital data warehouses can be a source of progress by taking into account multisource, multidomain and multiscale data for the benefit of knowledge and patients, it nevertheless raises technical, organizational and legal issues that still need to be addressed. The objectives of this article are threefold: 1. to provide insight on public health stakes of development in Comprehensive Cancer Centers to manage cancer patients comprehensively; 2. to set out a challenge of structuring the data from within them; 3. to outline the legal issues of implementation to carry out real-world evidence studies. To meet objective 1, this article firstly proposed a discussion on the relevance of an integrated approach to manage cancer and the formidable tool that data warehouses represent to achieve this. To address objective 2, we carried out a literature review to screen the articles published in PubMed and Google Scholar through the end of 2022 on the use of data warehouses in French Comprehensive Cancer Centers. Seven publications dealing specifically with the issue of data structuring were selected. To achieve objective 3, we presented and commented on the main aspects of French and European legislation and regulations in the field of health data, hospital data warehouses and real-world evidence.

Abemaciclib plus endocrine therapy for hormone receptor-positive, HER2-negative, node-positive, high-risk early breast cancer (monarchE): results from a preplanned interim analysis of a randomised, open-label, phase 3 trial

BACKGROUND

Adjuvant abemaciclib plus endocrine therapy previously showed a significant improvement in invasive disease-free survival and distant relapse-free survival in hormone receptor-positive, human epidermal growth factor receptor 2 (HER2; also known as ERBB2)-negative, node-positive, high-risk, early breast cancer. Here, we report updated results from an interim analysis to assess overall survival as well as invasive disease-free survival and distant relapse-free survival with additional follow-up.

METHODS

In monarchE, an open-label, randomised, phase 3 trial, adult patients (aged ≥18 years) who had hormone receptor-positive, HER2-negative, node-positive, early breast cancer at a high risk of recurrence with an Eastern Cooperative Oncology Group performance status of 0 or 1 were recruited from 603 sites including hospitals and academic and community centres in 38 countries. Patients were randomly assigned (1:1) by means of an interactive web-based response system (block size of 4), stratified by previous chemotherapy, menopausal status, and region, to receive standard-of-care endocrine therapy of physician's choice for up to 10 years with or without abemaciclib 150 mg orally twice a day for 2 years (treatment period). All therapies were administered in an open-label manner without masking. High-risk disease was defined as either four or more positive axillary lymph nodes, or between one and three positive axillary lymph nodes and either grade 3 disease or tumour size of 5 cm or larger (cohort 1). A smaller group of patients were enrolled with between one and three positive axillary lymph nodes and Ki-67 of at least 20% as an additional risk feature (cohort 2). This was a prespecified overall survival interim analysis planned to occur 2 years after the primary outcome analysis for invasive disease-free survival. Efficacy was assessed in the intention-to-treat population. Safety was assessed in all treated patients. The study is registered with ClinicalTrials.gov, NCT03155997, and is ongoing.

FINDINGS

Between July 17, 2017, and Aug 12, 2019, 5637 patients were randomly assigned (5601 [99·4%] were women and 36 [0·6%] were men). 2808 were assigned to receive abemaciclib plus endocrine therapy and 2829 were assigned to receive endocrine therapy alone. At a median follow-up of 42 months (IQR 37-47), median invasive disease-free survival was not reached in either group and the invasive disease-free survival benefit previously reported was sustained: HR 0·664 (95% CI 0·578-0·762, nominal p<0·0001). At 4 years, the absolute difference in invasive disease-free survival between the groups was 6·4% (85·8% [95% CI 84·2-87·3] in the abemaciclib plus endocrine therapy group vs 79·4% [77·5-81·1] in the endocrine therapy alone group). 157 (5·6%) of 2808 patients in the abemaciclib plus endocrine therapy group died compared with 173 (6·1%) of 2829 patients in the endocrine therapy alone group (HR 0·929, 95% CI 0·748-1·153; p=0·50). The most common grade 3-4 adverse events were neutropenia (in 548 [19·6%] of 2791 patients receiving abemaciclib plus endocrine therapy vs 24 [0·9%] of 2800 patients in the endocrine therapy alone group), leukopenia (318 [11·4%] vs 11 [0·4%]), and diarrhoea (218 [7·8%] vs six [0·2%]). Serious adverse events occurred in 433 (15·5%) of 2791 patients receiving abemaciclib plus endocrine therapy versus 256 (9·1%) of 2800 receiving endocrine therapy. There were two treatment-related deaths in the abemaciclib plus endocrine therapy group (diarrhoea and pneumonitis) and none in the endocrine therapy alone group.

INTERPRETATION

Adjuvant abemaciclib reduces the risk of recurrence. The benefit is sustained beyond the completion of treatment with an absolute increase at 4 years, further supporting the use of abemaciclib in patients with high-risk hormone receptor-positive, HER2-negative early breast cancer. Further follow-up is needed to establish whether overall survival can be improved with abemaciclib plus endocrine therapy in these patients.

FUNDING

Eli Lilly.

Everolimus Added to Adjuvant Endocrine Therapy in Patients With High-Risk Hormone Receptor-Positive, Human Epidermal Growth Factor Receptor 2-Negative Primary Breast Cancer

PURPOSE

Everolimus, an oral inhibitor of the mammalian target of rapamycin, improves progression-free survival in combination with endocrine therapy (ET) in postmenopausal women with aromatase inhibitor-resistant metastatic breast cancer. However, the benefit of adding everolimus to ET in the adjuvant setting in early breast cancer is unknown.

PATIENTS AND METHODS

In this randomized double-blind phase III study, women with high-risk, hormone receptor-positive, human epidermal growth factor receptor 2-negative primary breast cancer were randomly assigned to everolimus or placebo for 2 years combined with standard ET. Stratification factors included ET agent, receipt of neoadjuvant versus adjuvant chemotherapy, progesterone receptor status, duration of ET before random assignment, and lymph node involvement. The primary end point was disease-free survival (DFS). The trial is registered with ClinicalTrials.gov (identifier: NCT01805271).

RESULTS

Between June 2013 and March 2020, 1,278 patients were randomly allocated to receive everolimus or placebo. At the first interim analysis, the trial was stopped for futility and a full analysis undertaken once data snapshot complete. One hundred forty-seven patients have had a DFS event reported and at 3 years, DFS did not differ between patients who received ET plus everolimus (88% [95% CI, 85 to 91]) or ET plus placebo (89% [95% CI, 86 to 91; hazard ratio, 0.95; 95% CI, 0.69 to 1.32; P = .77]). Grade ≥ 3 adverse events were reported in 22.9% of patients (29.9% with everolimus v 15.9% with placebo, P < .001). 53.4% everolimus-treated patients permanently discontinued experimental treatment early compared with placebo-treated 22.3%.

CONCLUSION

Among high-risk patients, everolimus added to adjuvant ET did not improve DFS. Tolerability was a concern, with more than half of patients stopping everolimus before study completion. Everolimus cannot be recommended in the adjuvant setting.

The predictive value of patient-reported outcomes on the impact of breast cancer treatment-related quality of life

Purpose

Patient-reported outcomes (PROs) have been widely used to measure breast cancer (BC) treatment outcomes. However, evidence is still limited on using routinely PROs to personalize treatment decision-making, including or not chemotherapy, targeted therapy, and radiotherapy. Using patient baseline PRO scores, we aimed to use PROs before treatment initiation to predict improvement or decline in health-related quality of life (HRQoL) due to treatment that they receive.

Methods

In two French cancer sites, women with non-metastatic BC completed the EORTC QLQ-C30 and QLQ-BR23 and BREAST-Q questionnaires to assess their PROs at baseline and again at 6 months. The outcome measured was post-operative change in PROs with minimal important difference for QLQ-C30 domains. We performed multivariate ordinal logistic regression to estimate the incremental probability of post-operative PRO improvements and deteriorations depending upon treatment options and baseline HRQoL.

Results

One hundred twenty-seven women completed questionnaires. Chemotherapy had significant negative impacts on Global health status (GHS) and on physical and social functioning. Chemotherapy and radiotherapy increased patient fatigue scores after adjusting for clinical factors (p< 0.01 and p< 0.05, respectively). The incremental probability of GHS deteriorations for chemotherapy was +0.3, +0.5, and +0.34 for patients with baseline GHS scores of 40, 70, and 100, respectively. This showed that different pre-treatment PROs might predict differential effects of chemotherapy on women change in HRQoL.

Conclusion

Patients with different baseline PRO scores may experience dissimilar impacts from BC treatments on post-operative PROs in terms of improvements and deteriorations. Oncologists might decide to adapt the treatment option based on a given level of the negative impact. Future studies should concentrate on incorporating this information into routine clinical decision-making strategies to optimize the treatment benefit for patients.

Genomics to select treatment for patients with metastatic breast cancer

Cancer progression is driven in part by genomic alterations¹. The genomic characterization of cancers has shown interpatient heterogeneity regarding driver alterations², leading to the concept that generation of genomic profiling in patients with cancer could allow the selection of effective therapies^3,4. Although DNA sequencing has been implemented in practice, it remains unclear how to use its results. A total of 1,462 patients with HER2-non-overexpressing metastatic breast cancer were enroled to receive genomic profiling in the SAFIR02-BREAST trial. Two hundred and thirty-eight of these patients were randomized in two trials (nos. NCT02299999 and NCT03386162) comparing the efficacy of maintenance treatment⁵ with a targeted therapy matched to genomic alteration. Targeted therapies matched to genomics improves progression-free survival when genomic alterations are classified as level I/II according to the ESMO Scale for Clinical Actionability of Molecular Targets (ESCAT)⁶ (adjusted hazards ratio (HR): 0.41, 90% confidence interval (CI): 0.27-0.61, P < 0.001), but not when alterations are unselected using ESCAT (adjusted HR: 0.77, 95% CI: 0.56-1.06, P = 0.109). No improvement in progression-free survival was observed in the targeted therapies arm (unadjusted HR: 1.15, 95% CI: 0.76-1.75) for patients presenting with ESCAT alteration beyond level I/II. Patients with germline BRCA1/2 mutations (n = 49) derived high benefit from olaparib (gBRCA1: HR = 0.36, 90% CI: 0.14-0.89; gBRCA2: HR = 0.37, 90% CI: 0.17-0.78). This trial provides evidence that the treatment decision led by genomics should be driven by a framework of target actionability in patients with metastatic breast cancer.

Targeting of MCL-1 in breast cancer-associated fibroblasts reverses their myofibroblastic phenotype and pro-invasive properties

Cancer-associated fibroblasts (CAF) are a major cellular component of epithelial tumors. In breast cancers in particular these stromal cells have numerous tumorigenic effects in part due to their acquisition of a myofibroblastic phenotype. Breast CAFs (bCAFs) typically express MCL-1. We show here that pharmacological inhibition or knock down of this regulator of mitochondrial integrity in primary bCAFs directly derived from human samples mitigates myofibroblastic features. This decreases expression of genes involved in actomyosin organization and contractility (associated with a cytoplasmic retention of the transcriptional regulator, yes-associated protein-YAP) and decreases bCAFs ability to promote cancer cells invasion in 3D coculture assays. Our findings underscore the usefulness of targeting MCL-1 in breast cancer ecosystems, not only to favor death of cancer cells but also to counteract the tumorigenic activation of fibroblasts with which they co-evolve. Mechanistically, pharmacological inhibition of MCL-1 with a specific BH3 mimetic promotes mitochondrial fragmentation in bCAFs. Inhibition of the mitochondrial fission activity of DRP-1, which interacts with MCL-1 upon BH3 mimetic treatment, allows the maintenance of the myofibroblastic phenotype of bCAFs.

Brain Neural Progenitors are New Predictive Biomarkers for Breast Cancer Hormonotherapy

Heterogeneity of the tumor microenvironment (TME) is one of the major causes of treatment resistance in breast cancer. Among TME components, nervous system role in clinical outcome has been underestimated. Identifying neuronal signatures associated with treatment response will help to characterize neuronal influence on tumor progression and identify new treatment targets. The search for hormonotherapy-predictive biomarkers was implemented by supervised machine learning (ML) analysis on merged transcriptomics datasets from public databases. ML-derived genes were investigated by pathway enrichment analysis, and potential gene signatures were curated by removing the variables that were not strictly nervous system specific. The predictive and prognostic abilities of the generated signatures were examined by Cox models, in the initial cohort and seven external cohorts. Generated signature performances were compared with 14 other published signatures, in both the initial and external cohorts. Underlying biological mechanisms were explored using deconvolution tools (CIBERSORTx and xCell). Our pipeline generated two nervous system-related signatures of 24 genes and 97 genes (NervSign24 and NervSign97). These signatures were prognostic and hormonotherapy-predictive, but not chemotherapy-predictive. When comparing their predictive performance with 14 published risk signatures in six hormonotherapy-treated cohorts, NervSign97 and NervSign24 were the two best performers. Pathway enrichment score and deconvolution analysis identified brain neural progenitor presence and perineural invasion as nervous system-related mechanisms positively associated with NervSign97 and poor clinical prognosis in hormonotherapy-treated patients. Transcriptomic profiling has identified two nervous system-related signatures that were validated in clinical samples as hormonotherapy-predictive signatures, meriting further exploration of neuronal component involvement in tumor progression.

Significance

The development of personalized and precision medicine is the future of cancer therapy. With only two gene expression signatures approved by FDA for breast cancer, we are in need of new ones that can reliably stratify patients for optimal treatment. This study provides two hormonotherapy-predictive and prognostic signatures that are related to nervous system in TME. It highlights tumor neuronal components as potential new targets for breast cancer therapy.

Influence of inputs for bone lesion segmentation in longitudinal 18F-FDG PET/CT imaging studies

In metastatic breast cancer, bone metastases are prevalent and associated with multiple complications. Assessing their response to treatment is therefore crucial. Most deep learning methods segment or detect lesions on a single acquisition while only a few focus on longitudinal studies. In this work, 45 patients with baseline (BL) and follow-up (FU) images recruited in the context of the EPICURE_seinmeta study were analyzed. The aim was to determine if a network trained for a particular timepoint can generalize well to another one, and to explore different improvement strategies. Four networks based on the same 3D U-Net framework to segment bone lesions on BL and FU images were trained with different strategies and compared. These four networks were trained 1) only with BL images 2) only with FU images 3) with both BL and FU images 4) only with FU images but with BL images and bone lesion segmentations registered as input channels. With the obtained segmentations, we computed the PET Bone Index (PBI) which assesses the bone metastases burden of patients and we analyzed its potential for treatment response evaluation. Dice scores of 0.53, 0.55, 0.59 and 0.62 were respectively obtained on FU acquisitions. The under-performance of the first and third networks may be explained by the lower SUV uptake due to treatment response in FU images compared to BL images. The fourth network gives better results than the second network showing that the addition of BL PET images and bone lesion segmentations as prior knowledge has its importance. With an AUC of 0.86, the difference of PBI between two acquisitions could be used to assess treatment response. Clinical relevance- To assess the response to treatment of bone metastases, it is crucial to detect and segment them on several acquisitions from a same patient. We proposed a completely automatic method to detect and segment these metastases on longitudinal 18F-FDG PET/CT images in the context of metastatic breast cancer. We also proposed an automatic PBI to quantitatively assess the evolution of the bone metastases burden of patient and to automatically evaluate their response to treatment.

Factors associated with enrolment in clinical trials among women with early-stage breast cancer

Background

Clinical trials allow development of innovative treatments and ameliorate the quality of clinical care in oncology. Data show that only a minority of patients are enrolled in clinical trials. We assessed enrolment in clinical trials and its correlates among women with early breast cancer.

Methods

We included 9516 patients with stage I-III breast cancer from the multicenter, prospective CANTO study (NCT01993498), followed-up until year 4 (Y4) post-diagnosis. We assessed factors associated with enrolment using multivariable logistic regression. In exploratory, propensity score matched analyses, we used multiple linear regression to evaluate the relationship of enrolment in clinical trials with the European Organisation for Research and Treatment of Cancer Quality Of Life (QoL) questionnaire (EORTC QLQ-C30) Summary Score and described clinical outcomes (distant disease event, invasive disease event, and death by any cause) according to enrolment.

Results

Overall, 1716 patients (18%) were enrolled in a clinical trial until Y4 post-diagnosis of breast cancer. Socioeconomic factors were not associated with enrolment. Centres of intermediate volume were most likely to enrol patients in clinical trials [versus low volume, odds ratio 1.45 (95% confidence interval (CI) 1.08-1.95), P = 0.0124]. Among 2118 propensity score matched patients, enrolment was associated with better QoL at Y4 (adjusted mean difference versus not enrolled 1.37, 95% CI 0.03-2.71, P = 0.0458), and clinical outcomes (enrolled versus not enrolled, distant disease event 7.3% versus 10.1%, P = 0.0206; invasive disease event 8.2% versus 10.5%, P = 0.0732; death by any cause 2.8% versus 3.7%, P = 0.2707).

Conclusions

In this large study, one in five patients enrolled on a clinical trial until Y4 after diagnosis of early breast cancer. Geographical and centre-related factors were significantly associated with enrolment in clinical trials. Inclusion in clinical trials seemed associated with improved QoL and clinical outcomes. Access to innovation for early-stage breast cancer patients should be encouraged and facilitated by overcoming organizational and geographical barriers to recruitment.

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The proportion of patients who access innovation through participation in clinical trials is generally limited.

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Rate of enrolment in clinical trials among women with early breast cancer exceeded what previously found in other settings.

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Clinical and geographical factors were associated to access to innovation in clinical trials.

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Enrolment in clinical trials is associated with better quality of life and clinical outcomes.

Abstract CT517: Amcenestrant, an oral selective estrogen receptor (ER) degrader (SERD), in ER+/HER2- advanced breast cancer (aBC): combined biomarker analyses from a Phase 1/2 study in postmenopausal women and a Phase 1 study in postmenopausal Japanese women

Background: Amcenestrant is an optimized oral SERD that has shown safety and clinical benefit in patients (pts) with wild-type (WT) and mutated ESR1 aBC. Here we provide a pooled analysis of biomarkers from two studies in heavily-pretreated, postmenopausal women with ER+/HER2- aBC.

Methods: Pooled analysis included study data from AMEERA-1 (NCT03284957), in which pts received single-agent amcenestrant in dose escalation (20-600 mg QD or 300 mg BID) and dose expansion (400 mg QD), and from AMEERA-2 (NCT03816839), in which Japanese pts received single-agent amcenestrant at 400 mg QD or 300 mg BID. Mutational profiling of plasma circulating cell-free DNA was conducted by droplet digital polymerase chain reaction (ddPCR) for 12 pathogenic ESR1 mutations at baseline (BL) and on treatment (OT; Cycle 2, Day 28), and by next-generation sequencing (NGS; 77-gene panel) at BL and end of treatment (EOT). Clinical benefit (CB; complete response + partial response [PR] + stable disease ≥ 24 weeks) was assessed in pooled pts who received amcenestrant≥ 150 mg QD or BID. In tumor tissue, ER, progesterone receptor (PgR), Ki67 and Bcl-2 expression levels over time were assessed by immunohistochemistry; functional ER pathway activity was assessed by gene set variation analysis with RNA-seq data (ER activity score).

Results: Among pts with data for ESR1 mutation status at BL (N = 80; ddPCR), 41 pts were WT and 39 pts had at least one ESR1 mutation, with D538G and Y537S the most prevalent. CB was observed in pts with both WT (13 pts) and mutated ESR1 (12 pts) at BL. The most frequent pathogenic mutations detected in pts (N = 79; NGS) at BL were ESR1 (49%), followed by PI3KCA (46%)and TP53 (33%). In response-evaluable pts with ESR1 mutational profiling at BL and OT (N = 40; ddPCR), 17 of 19 pts with ESR1 mutation at BL showed a decrease in ESR1 mutation allele frequency, independently of clinical benefit. Eight pts showed an increase (7/25 no CB and 1/15 CB). Among 17 pts with biopsies, pts with ER or PgR -/low (H-score: 0-3) at BL did not derive benefit from treatment. In the remaining patients with ER high (H-score ≥ 140), no difference between pts with and without CB was observed in ER, Bcl-2 or ER activity score, while pts with CB had a tendency for lower Ki67. ER and PgR decreased upon treatment independently of CB, while ER activity score and Ki67 mostly decreased in pts with CB and mostly increased in pts without CB.

Conclusions: In postmenopausal women with ER+/HER2- aBC treated with single-agent amcenestrant, low Ki67 at BL and the pharmacodynamic decrease of Ki67 and ER activation score by amcenestrant trended toward an association with CB, whereas increase in ESR1 mutation allele frequency on treatment trended toward an association with lack of CB. Clinical benefit was observed in both pts with WT and mutated ESR1 at BL.

Citation Format: Hiroji Iwata, Aditya Bardia, Simon Lord, Hannah M. Linden, Mario Campone, Kenji Tamura, Kan Yonemori, Toru Mukohara, Cécile Combeau, Nils Ternes, Dimitri Carene, Jeff Ming, Joon Sang Lee, Marina Celanovic, Anne-Laure Bauchet, Monsif Bouaboula, Tomoyuki Tanaka, Yumiko Kawabata, Sarat Chandarlapaty. Amcenestrant, an oral selective estrogen receptor (ER) degrader (SERD), in ER+/HER2- advanced breast cancer (aBC): combined biomarker analyses from a Phase 1/2 study in postmenopausal women and a Phase 1 study in postmenopausal Japanese women [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr CT517.

Alpelisib (ALP) + fulvestrant (FUL) in patients (pts) with hormone receptor–positive (HR+), human epidermal growth factor receptor 2–negative (HER2−) advanced breast cancer (ABC): Biomarker (BM) analyses by next-generation sequencing (NGS) from the SOLAR-1 study

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Background: PIK3CA mutations (mut; ~40% of HR+, HER2– ABC) are linked to poor prognosis. In SOLAR-1, ALP (PI3Kα-selective inhibitor and degrader) + FUL improved progression-free survival (PFS) vs placebo (PBO) + FUL in pts with PIK3CA-mutated HR+, HER2– ABC. Here, we focus on efficacy data by gene alterations in SOLAR-1 PIK3CA-altered (alt) cohort. Methods: SOLAR-1 was a phase 3, randomized, double-blind study of ALP (or PBO) + FUL in HR+, HER2– ABC progressing on/after an aromatase inhibitor. Baseline tissue samples with enough quantity/quality (N = 398) were retrospectively tested by NGS (FoundationOne CDx 324-gene panel) and pts grouped by PIK3CA-alteration status. Clinical benefit was assessed using PFS and hazard ratio (HR) based on tumor mutational burden (TMB) and gene alteration status in the PIK3CA-alt cohort. No multiplicity adjustment was made. Results: PIK3CA-alt (ALP, n = 120; PBO, n = 117) and PI3KCA-non-alt (ALP, n = 81; PBO, n = 80) cohorts had differential gene alteration landscapes. In the PIK3CA-alt cohort, ALP + FUL clinical benefit was seen across TMB quartiles (Q1: 0 -<2.52, Q2: 2.52 -<3.78, Q3: 3.78 -<5.04, Q4: ≥ 5.04 mut/megabase). ALP + FUL had greater benefit in pts with alt vs non-alt FGFR1/ 2 (Table). ALP + FUL benefit was independent of alterations in TP53, ESR1, CCND1, MAP3K1, and ARID1A and limited in MYC- and RAD21-alt cohorts . ALP + FUL benefit was seen in pts with alt genes in the MAPK (HR [95% CI] vs PBO: alt 0.43 [0.23 - 0.80]; non-alt 0.56 [0.40 - 0.79]) and PI3K (in addition to PIK3CA; alt 0.68 [0.38 - 1.23]; non-alt 0.48 [0.34 - 0.68]) pathways, and implicated in CDK4/6i resistance (alt 0.52 [0.30 - 0.89]; non-alt 0.53 [0.37 - 0.76]). Conclusions: The unique mut profile of PIK3CA-alt tumors did not affect ALP + FUL benefit in pts with HR+, HER2– ABC. Clinical benefit was maintained regardless of alterations in most BMs, including ESR1 and genes implicated in CDK4/6i resistance, consistent with ALP targeting the PIK3CA driver oncogene. Clinical trial information: NCT#02437318; EUDRA CT#2015-000340-42. [Table: see text]

PERCIST-like response assessment with FDG PET based on automatic segmentation of all lesions in metastatic breast cancer

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Background: In metastatic breast cancer (MBC), treatment response is often assessed with FDG PET per PERCIST which evaluates changes in SULpeak of the single hottest tumor lesion identified on the baseline and follow-up images. PERCIST therefore does not consider tumor heterogeneity. This work aims to compare responses determined with the automatic segmentation of all lesions to response determined manually per PERCIST. Methods: 10 MBC patients (61±14 y/o) undergoing either chemo- or hormonotherapy were randomly selected from the prospective EPICURE study (NCT03958136). A baseline and two follow-up FDG PET were acquired at pre-, early- (1 month) and mid-treatment times for each patient. All metastatic lesions on all images were manually segmented by experts. Using the Advanced Normalization Tools (ANTs) image registration method, we wrapped baseline lesion segmentations to automatically obtain the follow-up ones. These registered segmentations were compared to the ones done manually using standard biomarkers: SULpeak, lesion size and Total Lesion Glycolysis (TLG). Differences between baseline and follow-up images were visually represented by coloring the follow-up segmentations: in green for responsive lesions (decreasing SULpeak) and in red for progressive ones (increasing SULpeak). Two expert physicians were then asked to evaluate treatment response while seeing these colored segmentations. They assessed the FDG PET images in pairs, evaluating for each patient the baseline and one of the corresponding follow-ups in a blinded manner: either the early- or the mid-treatment follow-up. Evaluations were then compared: i) early- vs mid-treatment response and ii) follow-up response vs patient’s clinical outcome. Results: Biomarkers extracted from the registered segmentations were similar to the ones extracted from the manual segmentations, with a Lin correlation coefficient of 0.92, 0.87 and 0.95 for the SULpeak, lesion size and TLG respectively. These findings were obtained within ̃10min, whereas the manual segmentation of the three PET images for any given patient took ̃1h. With the use of colored segmentations, early follow-up evaluations were predictive of mid-treatment response in 65% of the cases. The blinded physicians agreed with the clinical outcomes 85% and 95% of the time for the early- and mid-treatment images respectively. Conclusions: With segmentations automatically derived from ANTs registration, we managed to extract biomarkers that are comparable to the ones obtained with manual segmentations; both segmentations carried similar information. ANTs fast registration and biomarkers computation can make it a useful tool in clinical routine. In addition, lesion coloring helped evaluate treatment response and early-treatment follow-up images were shown to be predictive of mid-treatment response. Clinical trial information: NCT03958136.

AMEERA-4: A preoperative window-of-opportunity (WOO) study to assess the pharmacodynamic (PD) activity of amcenestrant or letrozole in postmenopausal patients with ER+/HER2− primary breast cancer

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Background: Amcenestrant is an optimized oral selective ER degrader (SERD) that antagonizes and degrades the ER and has demonstrated favorable preliminary safety and antitumor activity as monotherapy and in combination with palbociclib in postmenopausal patients with ER+/HER2− advanced breast cancer, irrespective of baseline (BL) ESR1 mutation status. Here we present the final results of AMEERA-4 (NCT04191382), a Phase 2 preoperative WOO study that evaluated the PD activity of two dose levels of amcenestrant or letrozole using paired biopsies assessed for biomarkers. Methods: Postmenopausal women with operable stage I–III (tumor size ≥ 10 mm by ultrasound) ER+/HER2− breast cancer and Ki67 levels ≥ 15% by local assessment were randomized 1:1:1 to amcenestrant 400 mg once daily (QD), amcenestrant 200 mg QD or letrozole 2.5 mg QD for 14 days before surgery. Antiproliferative activity, as measured centrally by change from BL in Ki67 using paired biopsies before and after a 14-day treatment with 2 different doses of amcenestrant vs letrozole, was the planned primary endpoint. Main secondary endpoints included ER target engagement, assessed through the change in ER expression measured by change from BL in H-Score, and safety. Results: Trial enrollment was voluntarily stopped early, as informative data supporting adjuvant development became available; therefore, no formal statistical comparisons were conducted. Among 105 randomized patients (amcenestrant 400 mg: n = 34, amcenestrant 200 mg: n = 36, letrozole: n = 35), 95 were treated and had available pre- and post-treatment Ki67 per central review (modified ITT population). No major imbalances in BL patient and tumor characteristics were observed. The geometric least squares means (LSM) estimate (95% CI) of Ki67 reduction was 75.9% (67.9, 81.9) for amcenestrant 400 mg, 68.2% (58.4, 75.7) for amcenestrant 200 mg and 77.7% (70.0, 83.4) for letrozole. The LSM estimate (95% CI) of absolute change from BL in ER H-score was −176.7 (−201.4, −152.0) for amcenestrant 400 mg, −202.9 (−226.1, −179.7) for amcenestrant 200 mg and −32.5 (−57.2, −7.7) for letrozole, with median relative changes of −65.3%, −68.3% and −9.5%, respectively. The incidence of treatment-related adverse events (TRAEs) was 21.2% for amcenestrant 400 mg, 22.2% for amcenestrant 200 mg and 25.7% for letrozole. No Grade ≥ 3 TRAEs occurred in any treatment arm. Conclusions: Both doses of amcenestrant demonstrated robust Ki67 reductions, strongly engaged the ER target, and continued to show a favorable safety profile in an early breast cancer population, consistent with previous published reports. Based on PD activity and safety, and emerging results from other ongoing amcenestrant trials, the 200 mg QD dose of amcenestrant was selected for our ongoing study in the adjuvant setting; AMEERA-6 (NCT05128773). Clinical trial information: NCT04191382.

Impact of HER2 Status on Pathological Response after Neoadjuvant Chemotherapy in Early Triple-Negative Breast Cancer

PURPOSE

Investigates the link between HER2 status and histological response after neoadjuvant chemotherapy in patients with early TNBC.

METHODS

We retrieved clinical and anatomopathological data retrospectively from 449 patients treated for the first time with standard neoadjuvant chemotherapy for early unilateral BC between 2005 and 2020. The primary endpoint was pathological complete response (pCR, i.e., ypT0 ypN0), according to HER2 status. Secondary endpoints included invasive disease-free survival (I-DFS) and overall survival (OS).

RESULTS

437 patients were included, and 121 (27.7%) patients had HER2-low tumours. The pCR rate was not significantly different between the HER2-low group vs. the HER2-0 group (35.7% versus 41.8%, p = 0.284) in either univariate analysis or multivariate analysis adjusted for TNM classification and grade (odds ratio [OR] = 0.70, confidence interval [CI] 95% 0.45-1.08). With a median follow-up of 72.9 months, no significant survival differences were observed between patients with HER2-low tumours vs. patients with HER2-0 tumours in terms of I-DFS (p = 0.487) and OS (p = 0.329).

CONCLUSIONS

In our cohort, HER2 status was not significantly associated with pCR in a manner consistent with data published recently on TNBC. However, the prognostic impact of HER2-low expression among TNBC patients warrants further evaluation.

COVID-19 Infections in Cancer Patients Were Frequently Asymptomatic: Description From a French Prospective Multicenter Cohort (PAPESCO-19)

Background

Cancer patients (CPs) are considered more vulnerable and as a high mortality group regarding COVID-19. In this analysis, we aimed to describe asymptomatic COVID (+) CPs and associated factors.

Methods

We conducted a prospective study in CPs and health care workers (HCWs) in 4 French cancer centers (PAPESCO [PAtients et PErsonnels de Santé des Centres de Lutte Contre le Cancer pendant l'épidémie de COvid-19] study). This analysis used data recorded between June 17, 2020 and November 30, 2020 in CPs (first 2 waves, no variants). At inclusion and quarterly, CPs reported the presence of predefined COVID-19 symptoms and had a blood rapid diagnostic test; a reverse transcription polymerase chain reaction (RT-PCR) was done in case of suspected infection.

Results

A total 878 CPs were included; COVID-19 prevalence was similar in both CPs (8%) and HCWs (9.5%); of the 70 CPs (8%) who were COVID (+), 29 (41.4%) were and remained asymptomatic; 241/808 of the COVID (-) (29.8%) were symptomatic. 18 COVID (+) were hospitalized (2% of CPs), 1 in intensive care unit (ICU) and 1 died (0.1% of CPs and 2.4% of symptomatic COVID [+] CPs). Only the inclusion center was associated with clinical presentation (in Nancy, Angers, Nantes, and Clermont-Ferrand: 65.4%, 35%, 28.6%, and 10% CPs were asymptomatic, respectively).

Conclusions

Seroprevalence of COVID-19 in CPs was similar to that observed in HCWs; mortality related to COVID-19 among CPs was 0.1%. More than 40% of COVID (+) CPs were asymptomatic and one third of COVID (-) CPs had symptoms. Only geographic origin was associated with the presence or absence of symptoms. Social distancing and protective measures must be applied in CPs at home and when hospitalized.

Supporting the Return to Work of Breast Cancer Survivors: From a Theoretical to a Clinical Perspective

Promoting the return to work of breast cancer survivors is of major interest to patients, healthcare and occupational health professionals, companies, governments, and researchers worldwide. We previously conducted a French consensus study resulting in a model describing the multifactorial process of the return to work of breast cancer survivors (the REWORK-BC model). Other work has identified the transtheoretical model as a relevant theoretical framework for interventions to promote the return to work of cancer survivors. In this opinion paper, we provide a theoretically-based clinical framework describing how to support breast cancer survivors at each stage of the return-to-work process. This clinical framework considers several essential aspects of supportive care for breast cancer survivors returning to work, such as: (i) helping the patient actively self-manage, by considering her to be the main decision-maker; (ii) respecting and adapting to the patient’s choice of professional project; (iii) respecting the temporality of the patient’s choices; (iv) proposing tailored interventions; (v) implementing simple tools to promote the return to work, shared representation between the patient and a multidisciplinary team, and improvement of working conditions and the knowledge of health and occupational professionals, and managers or employers; and (vi) maintaining certain flexibility aimed at proposing, but never imposing, changes in practices. This clinical framework, specific to breast cancer survivors, could be extrapolated to other tumor types, offering a practical guide for healthcare and occupational health professionals to better understand the return-to-work process of cancer survivors. This clinical framework aims to be a usable tool for any hospital or cancer care center wishing to implement a patient-centered intervention that promotes returning to work, regardless of the country.

Adjuvant Abemaciclib Combined with Endocrine Therapy for High Risk Early Breast Cancer: Safety and Patient-Reported Outcomes From the monarchE Study

BACKGROUND

In monarchE, abemaciclib plus endocrine therapy (ET) as adjuvant treatment of hormone receptor-positive, human epidermal growth factor 2-negative, high risk, early breast cancer demonstrated a clinically meaningful improvement in invasive disease-free survival versus ET alone. Detailed safety analyses conducted at a median follow-up of 27 months and key patient-reported outcomes (PRO) are presented.

PATIENTS AND METHODS

The safety population included all patients who received at least one dose of study treatment (n=5591). Safety analyses included incidence, management, and outcomes of common and clinically relevant adverse events (AEs). Patient-reported health-related quality-of-life, ET symptoms, fatigue, and side effect burden were assessed.

RESULTS

The addition of abemaciclib to ET resulted in higher incidence of Grade≥3 AEs (49.7% vs 16.3% with ET alone), predominantly laboratory cytopenias (e.g., neutropenia [19.6%]) without clinical complications. Abemaciclib-treated patients experienced more serious adverse events (SAEs; 13.3% vs 7.8%). Discontinuation of abemaciclib and/or ET due to AEs occurred in 18.5% of patients, mainly due to Grade1/2 AEs (66.8%). AEs were managed with comedications (e.g., antidiarrheals), abemaciclib dose holds (61.7%), and/or dose reductions (43.4%). Diarrhea was generally low grade (Grade1/2: 77%); Grade2/3 events were highest in the first month (20.5%), most short-lived (≤7 days) and did not recur. Venous thromboembolic events (VTE) were higher with abemaciclib+ET (2.5%) vs ET (0.6%); in the abemaciclib arm, increased VTE risk was observed with tamoxifen vs AIs (4.3% vs 1.8%). PROs were similar between arms, including being 'bothered by side effects of treatment', except for diarrhea. At ≥3 months, most patients reporting diarrhea reported "a little bit" or "somewhat".

CONCLUSION

In patients with high risk EBC, adjuvant abemaciclib+ET has an acceptable safety profile and tolerability is supported by PRO findings. Most AEs were reversible and manageable with comedications and/or dose modifications, consistent with the known abemaciclib toxicity profile.

Overall Survival with Ribociclib plus Letrozole in Advanced Breast Cancer

BACKGROUND

In a previous analysis of this phase 3 trial, first-line ribociclib plus letrozole resulted in significantly longer progression-free survival than letrozole alone among postmenopausal patients with hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer. Whether overall survival would also be longer with ribociclib was not known.

METHODS

Here we report the results of the protocol-specified final analysis of overall survival, a key secondary end point. Patients were randomly assigned in a 1:1 ratio to receive either ribociclib or placebo in combination with letrozole. Overall survival was assessed with the use of a stratified log-rank test and summarized with the use of Kaplan-Meier methods after 400 deaths had occurred. A hierarchical testing strategy was used for the analysis of progression-free survival and overall survival to ensure the validity of the findings.

RESULTS

After a median follow-up of 6.6 years, 181 deaths had occurred among 334 patients (54.2%) in the ribociclib group and 219 among 334 (65.6%) in the placebo group. Ribociclib plus letrozole showed a significant overall survival benefit as compared with placebo plus letrozole. Median overall survival was 63.9 months (95% confidence interval [CI], 52.4 to 71.0) with ribociclib plus letrozole and 51.4 months (95% CI, 47.2 to 59.7) with placebo plus letrozole (hazard ratio for death, 0.76; 95% CI, 0.63 to 0.93; two-sided P = 0.008). No new safety signals were observed.

CONCLUSIONS

First-line therapy with ribociclib plus letrozole showed a significant overall survival benefit as compared with placebo plus letrozole in patients with HR-positive, HER2-negative advanced breast cancer. Median overall survival was more than 12 months longer with ribociclib than with placebo. (Funded by Novartis; MONALEESA-2 ClinicalTrials.gov number, NCT01958021.).

Ribociclib plus letrozole in male patients with hormone receptor-positive, human epidermal growth factor receptor 2-negative advanced breast cancer: subgroup analysis of the phase IIIb CompLEEment-1 trial

PURPOSE

CompLEEment-1 (NCT02941926) is a single-arm, open-label, multicentre phase IIIb study investigating the safety and efficacy of ribociclib plus letrozole (RIB + LET) in a large, diverse cohort who have not received prior endocrine therapy (ET) for advanced disease. We present an exploratory analysis of male patients.

METHODS

Eligible patients with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) advanced breast cancer (ABC), who had no prior ET and ≤ 1 line of prior chemotherapy for advanced disease, received RIB + LET. Male patients also received goserelin or leuprolide. Primary endpoint was safety and tolerability; efficacy was a secondary endpoint.

RESULTS

In total, 39/3246 patients were male. Baseline characteristics were similar to the overall population. Male patients experienced fewer treatment-related adverse events (AEs) and treatment-related serious AEs compared with the overall population; fewer male patients had treatment-related AEs leading to discontinuation, adjustment/interruption, or additional therapy. One male patient died as a result of a serious AE that was not considered to be treatment-related. The most common AE was neutropenia; the incidence of grade ≥ 3 neutropenia in males (41.0%) was lower than in the overall population (57.2%). Median follow-up was 25.4 months; median time to progression was not reached in males versus 27.1 months for the overall population.

CONCLUSION

The clinical benefit and overall response rates in males were consistent with the overall population. This analysis demonstrates the safety and efficacy of ribociclib in a close-to-real-world setting, supporting the use of RIB + LET in male patients with HR+, HER2- ABC.

TRIAL REGISTRATION NUMBER

NCT02941926 (Registered 2016).

Abstract OT2-11-04: Ameera-1 Arm 5: Phase 1/2 study of amcenestrant (SAR439859), an oral selective estrogen receptor (ER) degrader (SERD), with abemaciclib in postmenopausal women with ER+/human epidermal growth factor receptor 2-negative (HER2-) advanced breast cancer

Background Endocrine therapy in combination with a targeted cyclin-dependent kinase (CDK) 4/6 inhibitor is the clinical standard for treatment of ER+/HER2- advanced breast cancer. Amcenestrant (SAR439859) is an optimized oral SERD with potent dual activity that antagonizes and degrades the ER, resulting in inhibition of the ER signaling pathway. In previous arms of the AMEERA-1 study, amcenestrant, as monotherapy or in combination with the CDK4/6 inhibitor palbociclib, demonstrated antitumor activity and a favorable safety profile in postmenopausal women with heavily pretreated ER+/HER2- advanced breast cancer. The objective of Arm 5 of the AMEERA-1 study is to evaluate safety and antitumor activity of amcenestrant in combination with the CDK4/6 inhibitor abemaciclib for patients with ER+/HER2- advanced breast cancer. Methods AMEERA-1 (NCT03284957) is an open-label, non-comparative, dose escalation and dose expansion Phase 1/2 study of amcenestrant as monotherapy, then in combination with other anti-cancer targeted therapies. Arm 5 investigates dose escalation (Part J) and dose expansion (Part K), of amcenestrant in combination with abemaciclib. Postmenopausal women with ER+/HER2- advanced breast cancer, ECOG performance status 0-1, and ≥ 6 months prior endocrine therapy are eligible. In Arm 5 (Parts J and K), ≤ 1 prior line of a single endocrine therapy for advanced disease is allowed. Prior treatment with fulvestrant or any other SERD is not allowed; in addition, prior therapy with CDK4/6 inhibitors for advanced disease is not allowed. Part J allows ≤ 1 prior chemotherapy for advanced disease, while prior chemotherapy for advanced disease is not allowed in Part K. Additional exclusion criteria in Arm 5 are prior drugs targeting the phosphoinositide 3-kinase axis; history of or concurrent pneumonitis; and history of or concurrent venous thromboembolism (i.e., deep vein thrombosis, pulmonary embolism, or cerebral venous sinus thrombosis). Part J evaluates the selected amcenestrant dose for combination therapy plus abemaciclib 150 mg twice daily (BID) (the approved standard dose) or abemaciclib 100 mg BID, taken in 28-day cycles. Additional dose levels of amcenestrant may be explored based on safety and pharmacokinetics (PK). The objective of Part J is to determine the recommended dose (RD) of abemaciclib in combination with the selected amcenestrant dose for combination therapy, based on preliminary safety, PK, and antitumor activity data. The primary endpoint in Part J is the incidence of treatment-related dose-limiting toxicities (DLTs) at Cycle 1. Approximately up to 12 DLT-evaluable patients will be needed to establish the RD of abemaciclib in combination with amcenestrant in Part J. In Part K, approximately 20 patients will be treated at the RD of abemaciclib for combination therapy with amcenestrant, the primary endpoint being safety and tolerability. Secondary endpoints include PK and antitumor activity. Funding: Sanofi.

Citation Format: Mario Campone, Sarat Chandarlapaty, Aditya Bardia, Patrick Neven, Katarina Petrakova, Peter Kabos, Valentina Boni, Sofia Braga, Marina Celanovic, Patrick Cohen, Alice Gosselin, Sylvaine Cartot-Cotton, Vasiliki Pelekanou, Hannah Linden. Ameera-1 Arm 5: Phase 1/2 study of amcenestrant (SAR439859), an oral selective estrogen receptor (ER) degrader (SERD), with abemaciclib in postmenopausal women with ER+/human epidermal growth factor receptor 2-negative (HER2-) advanced breast cancer [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr OT2-11-04.

Abstract P1-17-11: Updated data from AMEERA-1: Phase 1/2 study of amcenestrant (SAR439859), an oral selective estrogen receptor (ER) degrader (SERD), combined with palbociclib in postmenopausal women with ER+/HER2- advanced breast cancer

Background: In Arm 2 of the ongoing AMEERA-1 trial (NCT03284957), amcenestrant, an optimized oral SERD combined with the CDK4/6 inhibitor (CDK4/6i) palbociclib demonstrated favorable safety and encouraging antitumor activity among patients with endocrine-resistant ER+/HER2− advanced breast cancer in dose escalation (Part C) and dose expansion (Part D) (Chandarlapaty et al., ASCO 2021; abstract 1058). Here we report an update of safety, antitumor activity data, and progression-free survival (PFS), of amcenestrant 200 mg in combination with palbociclib. Analysis of genomic data, including modulation over time and correlation with clinical outcome, will also be presented. Methods: The trial enrolled postmenopausal women with ER+/HER2- locally-advanced or metastatic breast cancer with disease progression while on ≥ 6 months of prior endocrine therapy (ET) in the advanced setting, or who relapsed on adjuvant ET after the first 2 years of treatment or within 12 months of completing adjuvant ET. Prior chemotherapy (≤ 1) was allowed as well as prior CDK4/6i-based therapy (≤ 1, in Part C only). In this pooled analysis (N = 39), patients in Parts C + D received amcenestrant 200 mg once daily + palbociclib 125 mg (21 days on/7 days off), administered in 28-day cycles. Safety in the pooled analysis was reported using methods previously described (Chandarlapaty et al., ASCO 2021; abstract 1058). Data from investigator-assessed, response-evaluable patients in the pooled analysis without prior exposure to targeted therapies (N = 34) were used to evaluate antitumor activity per RECIST v1.1, including the objective response rate (ORR), clinical benefit rate (CBR), and PFS. Results: At a data cutoff of May 30, 2021, in the pooled analysis (N = 39), the median (range) duration of treatment exposure was 44.3 weeks (1-80). Of 39 patients, 24 (61.5%) had initiated at least 10 cycles (40 weeks) of treatment, with 20/39 (51.3%) still receiving ongoing treatment. Among the 34/39 (87.2%) patients in the response-evaluable population, median follow-up was 48.3 weeks with a PFS probability of being event free at 24 weeks of 78.2% (95% CI: 59.6%; 89.0%). Median PFS is not yet mature, with 14/34 (41.2%) patients having had a PFS event (all were progression events and no deaths occurred). The ORR was 11/34 (32.4%; all partial responses). Clinical benefit at 24 weeks was seen in 25/34 (CBR = 73.5%) patients. Median (range) time to first response was 16.3 weeks (8-32). Amcenestrant treatment-related adverse events (TRAEs) and palbociclib TRAEs, respectively, occurred in 27/39 (69.2%) and 35/39 (89.7%) patients for all grade events and in 5/39 (12.8%) and 18/39 (46.2%) patients for Grade ≥ 3 events. Non-hematological amcenestrant and palbociclib TRAEs are reported in Table 1. Neutrophil count decrease based on hematological laboratory abnormalities was observed in the majority of patients (94.9%; with Grade ≥ 3 in 56.4%).

Conclusions: Among postmenopausal women with endocrine-resistant ER+/HER2- advanced breast cancer, amcenestrant 200 mg in combination with the approved dose of palbociclib continues to demonstrate encouraging long-term antitumor activity, sustained clinical benefit, and a favorable safety profile consistent with previous results. Funding: Sanofi.

Table 1.Non-hematological amcenestrant and palbociclib TRAEs occurring in &gt; 10% of patientsPooled Analysis. Amcenestrant 200 mg + Palbociclib. (Parts C + D; N = 39)Amcenestrant Non-hematological TRAEs, n (%)All GradesGrade ≥ 3–Fatigue7 (17.9)0–Nausea7 (17.9)0–Arthralgia4 (10.3)0–Asthenia4 (10.3)0–Hot flush4 (10.3)0Palbociclib Non-hematological TRAEs, n (%)All GradesGrade ≥ 3–Fatigue12 (30.8)0–Nausea10 (25.6)0–Asthenia4 (10.3)0–Dysgeusia4 (10.3)0–Stomatitis4 (10.3)0

Citation Format: Sarat Chandarlapaty, Hannah M Linden, Patrick Neven, Katarina Petrakova, Aditya Bardia, Peter Kabos, Sofia Braga, Valentina Boni, Alice Gosselin, Marina Celanovic, Patrick Cohen, Gautier Paux, Vasiliki Pelekanou, Nils Ternès, Joon Sang Lee, Mario Campone. Updated data from AMEERA-1: Phase 1/2 study of amcenestrant (SAR439859), an oral selective estrogen receptor (ER) degrader (SERD), combined with palbociclib in postmenopausal women with ER+/HER2- advanced breast cancer [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P1-17-11.

Abstract GS2-01: Overall survival subgroup analysis by metastatic site from the phase 3 MONALEESA-2 study of first-line ribociclib + letrozole in postmenopausal patients with advanced HR+/HER2− breast cancer

Background: MONALEESA-2 (ML-2) recently reported a statistically significant overall survival (OS) benefit with first-line ribociclib (RIB) + letrozole (LET) over placebo (PBO) + LET in postmenopausal patients with HR+/HER2- advanced breast cancer (ABC) (median, 63.9 vs 51.4 months; hazard ratio, 0.76; 95% CI, 0.63-0.93; P = .004). Understanding OS outcomes in clinically relevant subgroups of patients is important for improving personalized care and prognosis. Here, we report the results of a prespecified exploratory OS analysis in select patient subgroups by baseline location and number of metastatic sites.. Methods: Postmenopausal patients with HR+/HER2− ABC were randomized 1:1 to receive first-line RIB or PBO with LET. Prespecified exploratory OS analyses were performed for subgroups of special interest by baseline location (bone only [yes or no], liver involvement [yes or no], liver or lung involvement [yes or no]) and number of metastatic sites (&lt; 3 or ≥ 3). The data are hypothesis generating since this analysis was exploratory and not powered for statistical significance.. Results: A total of 668 patients were included in the analysis. A consistent improvement in OS was observed with RIB + LET vs PBO + LET in all subgroups regardless of baseline metastatic site (Table). RIB + LET demonstrated an OS benefit over PBO + LET in clinically relevant subgroups by baseline location and number of metastatic sites, including subgroups of patients with liver metastases, liver or lung metastases, and ≥ 3 metastatic sites, who generally have a worse prognosis.. Conclusion: Consistent with the intent-to-treat population of ML-2, the results of this prespecified exploratory analysis demonstrated an OS benefit with RIB + LET independent of the site and number of metastatic lesions.

TableTreatment Arm (n)HR (95% CI)Bone-only metastasisYesRIB + LET (69)0.78 (0.50-1.21)PBO + LET (79)NoRIB + LET (265)0.77(0.61-0.96)PBO + LET (255)Liver involvementYesRIB + LET (59)0.81 (0.54-1.24)PBO + LET (72)NoRIB + LET (275)0.77 (0.62-0.97)PBO + LET (262)Liver or lung involvementYesRIB + LET (182)0.81(0.62-1.05)PBO + LET (190)NoRIB + LET (152)0.71 (0.53-0.96)PBO + LET (144)No. of metastatic sites&lt; 3RIB + LET (220)0.78(0.61-1.00)PBO + LET (222)≥ 3RIB + LET (114)0.71(0.51-0.98)PBO + LET (112)

Citation Format: Joyce O'Shaughnessy, Salomon M Stemmer, Howard A Burris, Yoon-Sim Yap, Gabe Sonke, Lowell Hart, Mario Campone, Katarina Petrakova, Eric P Winer, Wolfgang Janni, Pierfranco Conte, David A Cameron, Fabrice André, Carlos Arteaga, Juan Pablo Zarate, Arunava Chakravartty, Tetiana Taran, Fabienne Le Gac, Paolo Serra, Gabriel N Hortobagyi. Overall survival subgroup analysis by metastatic site from the phase 3 MONALEESA-2 study of first-line ribociclib + letrozole in postmenopausal patients with advanced HR+/HER2− breast cancer [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr GS2-01.

Abstract OT2-11-03: AMEERA-1 : Phase 1/2 study of amcenestrant (SAR439859), an oral selective estrogen receptor (ER) degrader (SERD), with alpelisib in postmenopausal women with ER+/human epidermal growth factor receptor 2-negative (HER2-)PIK3CA-mutated advanced breast cancer

Background Amcenestrant is an optimized oral SERD with potent dual activity of ER antagonism and degradation resulting in inhibition of ER signaling. Amcenestrant monotherapy or combination with palbociclib showed antitumor activity and a favorable safety profile in postmenopausal women with heavily pretreated ER+/HER2- mBC. PIK3CA mutations are associated with endocrine resistance in ER+/HER2- patients (pts). Published data support the addition of the PI3Kα inhibitor alpelisib to SERD therapy for these pts. Methods AMEERA-1 (NCT03284957) is an open-label, non-comparative, dose escalation and dose expansion Phase 1/2 study of amcenestrant as monotherapy, then in combination with other anti-cancer targeted therapies. Parts F and G investigate safety run-in and dose expansion, respectively, of amcenestrant in combination with alpelisib. Postmenopausal women with ER+/HER2- advanced breast cancer, PIK3CA mutated in tumor tissue or cfDNA, ECOG performance status 0-1, and ≥ 6 months prior endocrine therapy are eligible. Pts must have progressed on an aromatase inhibitor plus CDK4/6 inhibitor as first-line therapy for advanced disease. Part F allows ≤ 1 prior chemotherapy for advanced disease; no prior chemotherapy is allowed in Part G. Exclusion criteria in Parts F and G include prior drugs targeting the PI3K axis, type 1 diabetes, uncontrolled type 2 diabetes, history of severe cutaneous reactions, and ongoing osteonecrosis of the jaw. Part F assesses dose-limiting toxicities and pharmacokinetics (PK) of a standard dose of amcenestrant plus the approved dose of alpelisib (300 mg once daily). Additional amcenestrant doses or a lower dose of alpelisib may be explored based on safety and PK. The primary objective in Part F is to confirm the recommended phase 2 dose (RP2D) of amcenestrant in combination with alpelisib, based on safety. In Part G, approximately 34 pts will be treated at the RP2D, the primary endpoint being safety and tolerability. Secondary endpoints include PK and antitumor activity. This study is currently recruiting participants. This abstract was previously submitted to the 2021 European Society for Medical Oncology Annual Congress. Funding: Sanofi.

Citation Format: Mario Campone, Aditya Bardia, Peter Kabos, Sarat Chandarlapaty, Patrick Neven, Valentina Boni, Simon Lord, Sylvaine Cartot-Cotton, Marina Celanovic, Alice Gosselin, Vasiliki Pelekanou, Hannah M Linden. AMEERA-1 : Phase 1/2 study of amcenestrant (SAR439859), an oral selective estrogen receptor (ER) degrader (SERD), with alpelisib in postmenopausal women with ER+/human epidermal growth factor receptor 2-negative (HER2-)PIK3CA-mutated advanced breast cancer [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr OT2-11-03.

Abstract OT1-20-01: Feasibility of creation of a clinico-biological database: A prospective longitudinal cohort study of metastatic breast cancer patients (epicuresein)

Background: Each year 5 to 10% of new breast cancers are diagnosed with a metastatic staging. Metastatic breast cancer remains an incurable disease despite significant therapeutic advances in both supportive cares and targeted specific therapies. The disease is in most cases characterized by the disruption of systemic homeostasis (coinciding with multiple interactive and dependent parameters). Decision algorithms rely on a number of objective and subjective parameters which allow the therapeutic decision making process to become the most individualized or adapted. Extrinsic objectives parameters are currently based on EBM (evidence-based-medicine). Intrinsic subjective parameters are taken into account in decision-making: parameters that are linked to the oncologist's assumptions, such asthe sensitivity to the theoretical efficacy of treatments and the definition of sensitivity. Currently, the clinician rationalizes these therapeutic indications according to the prediction of the treatment response from the "phenotypic classification". Cancer is a complex disease relying on numerous elements in dynamic, organized and evolving interactions, and analysis of a complex system requires a global approach. The research hypothesis is to evolve from a reductionist, disjunctive, analytical view of the characterization of cell components (genes, transcripts, proteins, etc.) to a global, systemic, conjunctive and organizational vision: distinct datasets are linked and we need to unravel these underlying links. With this project, we want to demonstrate the ability to exploit complex data in healthcare and in particular in cancer management. We chose a specific metastatic breast cancer model. Methods: Our project is to integrate massive and heterogeneous data concerning the patient’s environment, personal and familial history, clinical and biological data, imaging, histological results, multi-omics data, and microbiota analysis. These characteristics are multiple and in dynamic interaction overtime. The main objective is to prove feasibility of creation of a clinico-biological database prospectively by collecting epidemiological, socio-economic, clinical, biological, pathological, multi-omics data and to identify characteristics related to the disease progression before treatment and within 15 years after treatment start from a cohort of 300 patients with a metastatic breast cancer treated in our institution. Results: The EPICURE trial opened in December 2018. Overall recruitment as of July 2021 was 116 patients; 72% had history of adjuvant therapy and 28% had immediately metastatic disease. We created three groups: HR+/Her2- (75% of enrolment); HER2+ (12%); and triple-negative breast cancer (13%). For 89% of patients, we obtained metastatic biopsy during screening and at date 20 metastatic biopsies for recurrence. For all patients, we collected blood sample following the flow chart and microbiota at the screening. Conclusion: EPICURE is an original and longitudinal prospective biocollection of metastatic breast cancer patients. We expect answering specific scientific questions regarding metastatic disease with heterogeneous data, especially by collecting data without a priori value or links each other. Clinical trial information: NCT03958136. Funding: EPICURE is funded by the FEDER European fundings, Astra Zeneca and Lilly

Citation Format: Mathilde Colombié, Pascal Jézéquel, Mathieu Rubeaux, Jean-Sebastien Frenel, Frédéric Bigot, Valérie Seegers, Mario Campone. Feasibility of creation of a clinico-biological database: A prospective longitudinal cohort study of metastatic breast cancer patients (epicuresein) [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr OT1-20-01.

Abstract P1-13-08: Patterns of adjuvant endocrine therapy, discontinuations, toxicities and quality of life: Development of a model for early discontinuation using the CANTO cohort

Abstract. Long-term adherence to adjuvant endocrine therapy (ET, tamoxifen and aromatase inhibitors) is paramount for patients with early-stage breast cancer. Adherence to adjuvant endocrine therapy is hampered by numerous side effects associated with sustained estrogen deprivation. We aimed to describe recent real-world patterns of therapy, patients’ discontinuations of ET, toxicities, quality of life (QoL) and to develop a predictive model of early ET discontinuation. Methods. We used the first 9595 patients of the French CANTO cohort (NCT01993498), to evaluate among 6238 premenopausal and postmenopausal patients with HR+/HER2- stage I-III BC, who were prescribed adjuvant ET: a. treatment patterns of adjuvant ET including change of ET prescription during the follow-up course b. ET-associated toxicities and c. impact on QoL. Independent variables included medical history and toxicities as measured by : Common Toxicity Criteria Adverse Events (CTCAE) v4, Patient-Reported Outcomes (PROs) including European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaires (QLQ-C30) and Breast Cancer Module (BR23), and Hospital Anxiety and Depression Scale (HADS). Treatment discontinuation and treatment change were determined on the basis of patient’s declaration and medical decisions reported in the CANTO eCRF. We used patient data at 4 months from therapy initiation to train and evaluate on a held-out test set a machine-learning model (gradient-boosted trees) that is predictive of time to early discontinuation i.e. permanent discontinuation before four years of additional therapy. Results. 4052 post-menopausal patients and 2186 premenopausal patients were included in this analysis. Median follow-up after ET initiation is 3 years and 2 months. 86% of post-menopausal patients were prescribed a non-steroidal AI initially and 92% of premenopausal patients received tamoxifen first. Discontinuation rate of the first adjuvant endocrine therapy at 1 year was 14% and 10% in premenopausal and post-menopausal patients, respectively. Among 741 post-menopausal and 340 premenopausal patients who started a second ET, discontinuation of the second prescribed adjuvant ET at 1 additional year of therapy is 30% in both populations. Patients who switched from a first adjuvant ET to a second or further one continued to have more treatment-related toxicities and associated decrements in QoL. Exclusions due to data completeness and outcome definition led to 5331 patients being used for the model (4264 in the training set and 1067 in the validation set). In that population, the permanent discontinuation rate at 3 years is 6%. Our prediction model of time to early discontinuation obtains a C-index of 0.78 in the held-out validation set. Conclusion. Tolerability and continued adherence to ET remains a challenge for many patients. Early discontinuation models may assist in identifying patients who are likely to interrupt their adjuvant ET. Adapted clinical management, including robust support and management of toxicities, as well as new and more tolerable adjuvant endocrine therapies may improve the clinical outcomes of these patients.

Citation Format: Felix Balazard, Aurélie Bertaut, Élise Bordet, Stéphane Mulard, Julie Blanc, Nathalie Briot, Gautier Paux, Asma Dhaini Merimeche, Olivier Rigal, Charles Coutant, Marion Fournier, Christelle Jouannaud, Patrick Soulie, Florence Lerebours, Paul-Henri Cottu, Olivier Tredan, Laurence Vanlemmens, Christelle Levy, Marie-Ange Mouret-Reynier, Mario Campone, Keri J. S. Brady, Medha Sasane, Megan Rice, Catherine Coulouvrat, Anne-Laure Martin, Alexandra Jacquet, Ines Vaz-Luis, Christina Herold, Barbara Pistilli. Patterns of adjuvant endocrine therapy, discontinuations, toxicities and quality of life: Development of a model for early discontinuation using the CANTO cohort [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P1-13-08.

Abstract PD9-08: Prognostic value of EndoPredict test in patients screened for UNIRAD, a UCBG randomized, double blind, phase III international trial evaluating the addition of everolimus (EVE) to adjuvant hormone therapy (HT) in women with high risk HR+, HER2- early breast cancer (eBC)

Background: The double blind randomized UNIRAD trial (NCT01805271) showed no evidence that adding Everolimus (EVE) to adjuvant endocrine therapy (EHT) for high-risk early breast cancer (BC) improved 3-year disease-free survival (iDFS) compared with EHT alone. In this trial, high risk was defined by any T and either ≥4N+, or ≥1N+ after neoadjuvant treatment, or ≥1N+ and EPclin high risk (EPCH) score ≥3.3. This sub analysis is aimed to verify prognostic added value of EndoPredict test results on outcomes in patients screened for the UNIRAD study.. Material and methods: From May 2015 to March 2020, 777 patients were screened with the EndoPredict test. Complete results were obtained for 767 of them. 662 pts were classified as EPCH and 429 were randomized in UNIRAD. 233 pts with EPCH and 105 pts with EPclin low risk (EPCL) were not randomized but followed up for iDFS. Statistical analysis: Kaplan-Meier estimates the association of the integrated molecular-clinico-pathologic EPclin score, and the 12-gene molecular EP score, with iDFS (primary endpoint) and dMFS (secondary endpoint). Independent prognostic added value of EPclin score was tested in a multivariate Cox model after adjusting on tumor characteristics (Grade and T, N). A two-sided p-value less than 0.05 considered as statistically significant, 95% confidence intervals reported with HR. Results: Median follow-up of the cohort was 36.6 mo (0-69) since EndoPredict test. As for the whole population, there was no significant difference in iDFS between treatment arms in the randomized EPCH group. On the other hand, EPclin was an independent prognostic factor for iDFS. 36 mo relapse rate from testing for patients in the EPCL group and the EPCH group was 0% and 7%, respectively (HR supposing continuous EPclin score: 2.36, 95%CI: 1.7-3.3, p &lt; .0001). This difference remained significant when assessed in a cox model with tumor size, number of positive nodes and tumor grade (HR: 1.96, 95%CI: 1.32-2.9, p=0.0008). Furthermore, EPclin results was independently correlated to distant metastatic free survival: 36 mo dMFS for patient in the EPCL and EPCH group was 100% and 94%, respectively (adjusted HR: 2.13, 95%CI:11.3-3.4, p = .0014). Of interest when assessing prognostic of patients within quartiles of EPclin Score (&lt;3.6; 3.6-4.1; ≥4.1-4.8; ≥ 4.8), 36 mo iDFS was 99%; 95%; 94% and 86%, respectively. Conclusion: These prospective results confirm the significance of EPclin score as an independent prognostic parameter in node positive ER+/HER2- eBC patients receiving standard adjuvant treatment. This information can be of importance for selection of specific adjuvant intervention, particularly chemotherapy and new targeted therapy. Further analysis on the EP score will be presented at the meeting.

Citation Format: Frederique Penault-Llorca, Florence Dalenc, Sylvie Chabaud, Paul Cottu, Djelila Allouache, David Cameron, Jean-Philippe Jacquin, Julien Grenier, Laurence Venat Bouvet, Apurna Jegannathen, Mario Campone, Francesco Del Piano, Marc Debled, Anne-Claire Hardy-Bessard, Sylvie Giacchetti, Philippe Barthelemy, Laure Kaluzinski, Audrey Mailliez, Marie-Ange Mouret-Reynier, Eric Legouffe, Anne Cayre, Mathilde Martinez, Catherine Delbaldo, Delphine Mollon-Grange, E. Jane Macaskill, Matthew Sephton, Laëtitia Stefani, Blaha Belgadi, Matthew Winter, Hubert Orfeuvre, Magali Lacroix-Triki, Herve Bonnefoi, Judith Bliss, Jean-Luc Canon, Jerome Lemonnier, Fabrice Andre, Thomas Bachelot. Prognostic value of EndoPredict test in patients screened for UNIRAD, a UCBG randomized, double blind, phase III international trial evaluating the addition of everolimus (EVE) to adjuvant hormone therapy (HT) in women with high risk HR+, HER2- early breast cancer (eBC) [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr PD9-08.

Abstract GS1-10: Clinical utility of molecular tumor profiling: Results from the randomized trial SAFIR02-BREAST

Background: While studies have shown feasibility and reported preliminary evidence of utility, there is no evidence that multigene sequencing improves outcome in patients with metastatic cancer. The aim of the present study was to assess the clinical utility of multigene sequencing and DNA copy number analyses.. Methods: In SAFIR02-BREAST (NCT: 02299999) and SAFIR-PI3K (NCT: 03386162), open-label multicentric phase II randomized trials, patients were selected if they had a Her2-negative metastatic breast cancer eligible to 1st or 2nd line chemotherapy. Patients underwent a pre-treatment biopsy of metastatic disease when feasible, followed by genomic analysis by next generation sequencing and SNParray. After 6 to 8 cycles of induction chemotherapy, patients without progressive disease and presenting an actionable genomic alteration, were randomized between targeted therapies matched to genomic alterations or maintenance chemotherapy. The primary objective was to evaluate whether targeted therapies guided by genomics improves progression-free survival (PFS) as compared to maintenance chemotherapy, in a pooled analyses of SAFIR02-BREAST and SAFIR-PI3K populations. A hierarchical testing was applied. The efficacy of targeted therapies matched to genomic alterations was first tested in patients presenting an ESCAT I/II alteration (ESMO Scale of Actionability of Molecular Targets). If a p value &lt;0.1 was observed in the first step, analyses were then performed in the Intent-to-treat population. Results: Out of the 1462 patients included, 238 (16%) were subsequently randomized between maintenance chemotherapy (n=81) and targeted therapy (n=157). In 115 patients presenting an ESCAT I/II genomic alteration, the median PFS was 9.1 months (90%CI: 7.1-9.8) and 2.8 (90%CI: 2.1-4.8) in matched targeted therapy and maintenance chemotherapy arms respectively (adjusted HR for stratification factors =0.41;90%CI: 0.27-0.61, p&lt;0.001). In the overall population, there was no significant difference in the duration of PFS between the two arms (adjusted HR: 0.77 (95%CI: 0.56- 1.06, p=0.109). ESCAT classification was highly predictive for the benefit of targeted therapies matched to genomic alterations (interaction test, p= 0.004). Targeted therapies matched to genomic alterations were not effective in patients without ESCAT I/II alteration (HR: 1.15, 95%CI: 0.76-1.75). The SNP array analyses (n=926) identified 21 genes altered more frequently in metastases as compared to primary tumors (TCGA+ METABRIC). Of these, focal TERT amplifications were associated with a poor outcome. Focal CDK4 amplifications were observed after resistance to CDK4 inhibitors. Finally, high HRD was associated with longer PFS in patients with BRCA mutation treated with olaparib (HR: 0.32 [95%CI: 0.12;0.83], p=0.013).. Conclusion: SAFIR02/PI3K trials report that the clinical use of multigene sequencing must be driven by a framework of actionability, and identifies new genomic alterations associated with metastatic evolution and drug resistance or sensitivity.

Citation Format: Fabrice André, Anthony Gonçalves, Thomas Filleron, Florence Dalenc, Amélie Lusque, Mario Campone, Marie-Paule Sablin, Hervé Bonnefoi, Ivan Bieche, Ludovic Lacroix, Alicia Tran-Dien, Marta Jimenez, Alexandra Jacquet, Qing Wang, Etienne Rouleau, David Gentien, Isabelle Soubeyran, Alain Morel, Monica Arnedos, Thomas Bachelot. Clinical utility of molecular tumor profiling: Results from the randomized trial SAFIR02-BREAST [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr GS1-10.