Trastuzumab and Pertuzumab in Patients with Non-Breast/Gastroesophageal HER2-Amplified Tumors: Results from the NCI-MATCH ECOG-ACRIN Trial (EAY131) Subprotocol J

PURPOSE

NCI-MATCH assigned patients with advanced cancer and progression on prior treatment, based on genomic alterations in pretreatment tumor tissue. Arm J (EAY131-J) evaluated the combination of trastuzumab/pertuzumab (HP) across HER2-amplified tumors.

PATIENTS AND METHODS

Eligible patients had high levels of HER2 amplification [copy number (CN) ≥7] detected by central next-generation sequencing (NGS) or through NCI-designated laboratories. Patients with breast/gastroesophageal adenocarcinoma and those who received prior HER2-directed therapy were excluded. Enrollment of patients with colorectal cancer was capped at 4 based on emerging data. Patients received HP IV Q3 weeks until progression or unacceptable toxicity. Primary endpoint was objective response rate (ORR); secondary endpoints included progression-free survival (PFS) and overall survival (OS).

RESULTS

Thirty-five patients were enrolled, with 25 included in the primary efficacy analysis (CN ≥7 confirmed by a central lab, median CN = 28). Median age was 66 (range, 31-80), and half of all patients had ≥3 prior therapies (range, 1-11). The confirmed ORR was 12% [3/25 partial responses (colorectal, cholangiocarcinoma, urothelial cancers), 90% confidence interval (CI) 3.4%-28.2%]. There was one additional partial response (urothelial cancer) in a patient with an unconfirmed ERBB2 copy number. Median PFS was 3.3 months (90% CI 2.0-4.1), and median OS 9.4 months (90% CI 5.0-18.9). Treatment-emergent adverse events were consistent with prior studies. There was no association between HER2 CN and response.

CONCLUSIONS

HP was active in a selection of HER2-amplified tumors (non-breast/gastroesophageal) but did not meet the predefined efficacy benchmark. Additional strategies targeting HER2 and potential resistance pathways are warranted, especially in rare tumors.

Entinostat, nivolumab and ipilimumab for women with advanced HER2-negative breast cancer: a phase Ib trial

We report the results of 24 women, 50% (N = 12) with hormone receptor-positive breast cancer and 50% (N = 12) with advanced triple-negative breast cancer, treated with entinostat + nivolumab + ipilimumab from the dose escalation (N = 6) and expansion cohort (N = 18) of ETCTN-9844 ( NCT02453620 ). The primary endpoint was safety. Secondary endpoints were overall response rate, clinical benefit rate, progression-free survival and change in tumor CD8:FoxP3 ratio. There were no dose-limiting toxicities. Among evaluable participants (N = 20), the overall response rate was 25% (N = 5), with 40% (N = 4) in triple-negative breast cancer and 10% (N = 1) in hormone receptor-positive breast cancer. The clinical benefit rate was 40% (N = 8), and progression-free survival at 6 months was 50%. Exploratory analyses revealed that changes in myeloid cells may contribute to responses; however, no correlation was noted between changes in CD8:FoxP3 ratio, PD-L1 status and tumor mutational burden and response. These findings support further investigation of this treatment in a phase II trial.

Enablers and barriers to accessing self-management support services for those living with and beyond cancer: A qualitative study using the theoretical domains framework

BACKGROUND

Supporting those living with and beyond cancer to self-manage their health can optimise health-related quality of life and reduce symptom burden. Self-management support (SMS) programmes have been shown to be effective, but uptake is often low. This qualitative study aimed to identify experienced and perceived enablers and barriers to accessing SMS services among those who had completed primary cancer treatment and were living with and beyond cancer.

METHODS

Participants were recruited through social media and cancer advocacy groups. Semi-structured telephone and online interviews were conducted. Transcripts were coded inductively based on participants' reported experiences. Statements related to factors that enable or inhibit access to SMS were then mapped to the Theoretical Domains Framework (TDF).

RESULTS

Twenty-six people participated. Six themes explain the factors that act as barriers and enablers which mapped to 11 TDF domains. Lack of knowledge of available SMS was a prominent barrier, as well as inaccessible services due to timing and place of delivery. Lack of confidence and emotional factors including fear were barriers to seeking SMS. Social influences shaped knowledge, attitudes and readiness to access SMS. Perceptions of SMS service goals and if in alignment with self-identity, intentions and goals also shaped decisions around accessing support.

CONCLUSIONS

While lack of knowledge and provider signposting were common barriers, findings suggest that other psychosocial and emotional factors may be barriers, even if SMS services are accessible. Findings are relevant for oncology healthcare services developing strategies to increase reach of SMS for those living with and beyond cancer.

The PD-1- and LAG-3-targeting bispecific molecule tebotelimab in solid tumors and hematologic cancers: a phase 1 trial

Tebotelimab, a bispecific PD-1×LAG-3 DART molecule that blocks both PD-1 and LAG-3, was investigated for clinical safety and activity in a phase 1 dose-escalation and cohort-expansion clinical trial in patients with solid tumors or hematologic malignancies and disease progression on previous treatment. Primary endpoints were safety and maximum tolerated dose of tebotelimab when administered as a single agent (n = 269) or in combination with the anti-HER2 antibody margetuximab (n = 84). Secondary endpoints included anti-tumor activity. In patients with advanced cancer treated with tebotelimab monotherapy, 68% (184/269) experienced treatment-related adverse events (TRAEs; 22% were grade ≥3). No maximum tolerated dose was defined; the recommended phase 2 dose (RP2D) was 600 mg once every 2 weeks. There were tumor decreases in 34% (59/172) of response-evaluable patients in the dose-escalation cohorts, with objective responses in multiple solid tumor types, including PD-1-refractory disease, and in LAG-3+ non-Hodgkin lymphomas, including CAR-T refractory disease. To enhance potential anti-tumor responses, we tested margetuximab plus tebotelimab. In patients with HER2+ tumors treated with tebotelimab plus margetuximab, 74% (62/84) had TRAEs (17% were grade ≥3). The RP2D was 600 mg once every 3 weeks. The confirmed objective response rate in these patients was 19% (14/72), including responses in patients typically not responsive to anti-HER2/anti-PD-1 combination therapy. ClinicalTrials.gov identifier: NCT03219268 .

Identifying homologous recombination deficiency in breast cancer: genomic instability score distributions differ among breast cancer subtypes

PURPOSE

A 3-biomarker homologous recombination deficiency (HRD) score is a key component of a currently FDA-approved companion diagnostic assay to identify HRD in patients with ovarian cancer using a threshold score of ≥ 42, though recent studies have explored the utility of a lower threshold (GIS ≥ 33). The present study evaluated whether the ovarian cancer thresholds may also be appropriate for major breast cancer subtypes by comparing the genomic instability score (GIS) distributions of BRCA1/2-deficient estrogen receptor-positive breast cancer (ER + BC) and triple-negative breast cancer (TNBC) to the GIS distribution of BRCA1/2-deficient ovarian cancer.

METHODS

Ovarian cancer and breast cancer (ER + BC and TNBC) tumors from ten study cohorts were sequenced to identify pathogenic BRCA1/2 mutations, and GIS was calculated using a previously described algorithm. Pathologic complete response (pCR) to platinum therapy was evaluated in a subset of TNBC samples. For TNBC, a threshold was set and threshold validity was assessed relative to clinical outcomes.

RESULTS

A total of 560 ovarian cancer, 805 ER + BC, and 443 TNBC tumors were included. Compared to ovarian cancer, the GIS distribution of BRCA1/2-deficient samples was shifted lower for ER + BC (p = 0.015), but not TNBC (p = 0.35). In the subset of TNBC samples, univariable logistic regression models revealed that GIS status using thresholds of ≥ 42 and ≥ 33 were significant predictors of response to platinum therapy.

CONCLUSIONS

This study demonstrated that the GIS thresholds used for ovarian cancer may also be appropriate for TNBC, but not ER + BC. GIS thresholds in TNBC were validated using clinical response data to platinum therapy.

Correlation of SUV on Early Interim PET with Recurrence-Free Survival and Overall Survival in Primary Operable HER2-Positive Breast Cancer (the TBCRC026 Trial)

Predictive biomarkers of response to human epidermal growth factor receptor 2 (HER2)-directed therapy are essential to inform treatment decisions. The TBCRC026 trial reported that early declines in tumor SUVs corrected for lean body mass (SULmax) on 18F-FDG PET/CT predicted a pathologic complete response (pCR) to HER2 therapy with neoadjuvant trastuzumab and pertuzumab (HP) without chemotherapy in estrogen receptor (ER)-negative, HER2-positive breast cancer. We hypothesized that 18F-FDG PET/CT SULmax parameters would predict recurrence-free survival (RFS) and overall survival (OS). Methods: Patients with stage II/III ER-negative, HER2-positive breast cancer received neoadjuvant HP (n = 88). pCR after HP alone was 22% (18/83), additional nonstudy neoadjuvant therapy was administered in 28% (25/88), and the majority received adjuvant therapy per physician discretion. 18F-FDG PET/CT was performed at baseline and at cycle 1, day 15 (C1D15). RFS and OS were summarized using the Kaplan-Meier method and compared between subgroups using logrank tests. Associations between 18F-FDG PET/CT (≥40% decline in SULmax between baseline and C1D15, or C1D15 SULmax ≤ 3) and pCR were evaluated using Cox regressions, where likelihood ratio CIs were reported because of the small numbers of events. Results: Median follow-up was 53.7 mo (83/88 evaluable), with 6 deaths and 14 RFS events. Estimated RFS and OS at 3 y was 84% (95% CI, 76%-92%) and 92% (95% CI, 87%-98%), respectively. A C1D15 SULmax of 3 or less was associated with improved RFS (hazard ratio [HR], 0.36; 95% CI, 0.11-1.05; P = 0.06) and OS (HR, 0.14; 95% CI, 0.01-0.85; P = 0.03), the latter statistically significant. The association of an SULmax decline of at least 40% (achieved in 59%) with RFS and OS did not reach statistical significance. pCR was associated with improved RFS (HR, 0.25; 95% CI, 0.01-1.24; P = 0.10) but did not reach statistical significance. Conclusion: For the first time, we report a potential association between a C1D15 SULmax of 3 or less on 18F-FDG PET/CT and RFS and OS outcomes in patients with ER-negative, HER2-positive breast cancer receiving neoadjuvant HP alone. If confirmed in future studies, this imaging-based biomarker may facilitate early individualization of therapy.

Room to Improve: An Audit of In-Hospital End-of-Life Care for Oncology Patients in a Tertiary Cancer Centre in Ireland During the COVID-19 Pandemic

The COVID-19 pandemic compounded isolation for patients through social distancing measures and staff shortages. We were concerned about the impact of COVID-19 on the quality of care provided at end-of-life in 2021 in a national cancer centre, and instigated the first ever review of the care of the dying. Quality of care was assessed retrospectively using a validated instrument developed by the United Kingdom's National Quality Board. Sixty-six patient deaths occurred in our cancer centre in 2021. The 'risk of dying' was documented in 65.2% of records. Palliative care services were involved in 77%, and pastoral care in 10.6%. What was important to the patient was documented in 24.2%. The 'quality-of-death' score was satisfactory for most but poor in 21.2%. Our study prompted change, including appointment of an end-of-life coordinator, development of a checklist to ensure comprehensive communication, expansion of the end-of-life committee to include junior doctors, and regular audit.

Impact of Muscle Measures on Outcome in Patients Receiving Endocrine Therapy for Metastatic Breast Cancer: Analysis of ECOG-ACRIN E2112

BACKGROUND

Observational data investigating the relationship between body habitus and outcomes in breast cancer have been variable and inconsistent, largely centered in the curative setting and focused on weight-based metrics. This study evaluated the impact of muscle measures on outcomes in patients with metastatic breast cancer receiving endocrine-based therapy.

METHODS

Baseline CT scans were collected from ECOG-ACRIN E2112, a randomized phase III placebo-controlled study of exemestane with or without entinostat. A CT cross-sectional image at the L3 level was extracted to obtain skeletal muscle mass and attenuation. Low muscle mass (LMM) was defined as skeletal muscle index <41 cm2/m2 and low muscle attenuation (LMA) as muscle density <25 HU or <33 HU if overweight/obese by body mass index (BMI). Multivariable Cox proportional hazard models determined the association between LMM or LMA and progression-free survival (PFS) and overall survival (OS). Correlations between LMM, LMA, and patient-reported outcomes were determined using 2-sample t tests.

RESULTS

Analyzable CT scans and follow-up data were available for 540 of 608 patients. LMM was present in 39% (n=212) of patients and LMA in 56% (n=301). Those with LMA were more likely to have obesity and worse performance status. LMM was not associated with survival (PFS hazard ratio [HR]: 1.13, P=.23; OS HR: 1.05, P=.68), nor was LMA (PFS HR: 1.01, P=.93; OS HR: 1.00, P=.99). BMI was not associated with survival. LMA, but not LMM, was associated with increased frequency of patient-reported muscle aches.

CONCLUSIONS

Both low muscle mass and density are prevalent in patients with hormone receptor-positive metastatic breast cancer. Muscle measures correlated with obesity and performance status; however, neither muscle mass nor attenuation were associated with prognosis. Further work is needed to refine body composition measurements and select optimal cutoffs with meaningful endpoints in specific breast cancer populations, particularly those living with metastatic disease.

Improving quality of life and symptom experience in patients with metastatic breast cancer: A systematic review of supportive care interventions

OBJECTIVE

The prognosis for individuals with metastatic breast cancer (MBC) has improved in recent decades. This expanding cohort has unique psychological and psychosocial needs, yet targeted supportive care interventions are underdeveloped. This systematic review seeks to summarise the available evidence on the effectiveness of supportive care interventions in improving quality of life and symptom experience of individuals living with MBC so that services can be developed to address the unmet needs of this cohort in future.

METHODS

Academic Search Complete, CINAHL, ERIC, Medline and SocINDEX were searched for publications investigating the effect of supportive care interventions specifically targeted at addressing the quality of life or symptom experience of individuals living with MBC. Three reviewers independently screened and selected studies. Quality appraisal and assessed risk of bias were carried out.

RESULTS

The search yielded 1972 citations. Thirteen studies met the inclusion criteria. Interventions included psychological (n = 3), end of life discussion and preparation (n = 2), physical activity (n = 4), lifestyle (n = 2), and medication self-management support (n = 2). Three studies reported significant improvement in quality of life, two of which reported improved symptom experience in at least one symptom. Three further physical activity interventions showed improvement in at least one of the symptoms investigated.

CONCLUSION

Studies reporting a statistically significant effect on quality of life and improved symptom experience were extremely heterogenous. We can tentatively suggest that multimodal and frequently administered interventions are effective, with physical activity interventions positively impacting on symptom experience, however further research is required.

A Phase I Study of a Combination of Liposomal Irinotecan and Veliparib in Solid Tumors

BACKGROUND

Multiple preclinical studies have shown cytotoxic synergy involving combinations of poly (ADP-ribose) polymerase (PARP) inhibitors and topoisomerase 1 (TOP1) inhibitors, but such combinations have proven too toxic in clinical trials. Liposomal irinotecan (nal-IRI) achieved similar intratumoral exposure with better antitumor activity than the conventional TOP1 inhibitor irinotecan in preclinical models. Tumor targeted delivery of TOP1 inhibitor using nal-IRI and an intermittent schedule of administration of PARP inhibitor may provide a tolerable combination.

METHODS

A phase I study was performed to evaluate the safety and tolerability of escalating doses of nal-IRI and the PARP inhibitor veliparib in patients with solid tumors resistant to standard treatments. Nal-IRI was administered on days 1 and 15 and veliparib on days 5-12 and 19-25 in 28-day cycles.

RESULTS

Eighteen patients were enrolled across 3 dose levels. Five patients encountered dose-limiting toxicities, including grade 3 diarrhea lasting more than 72 h in 3 patients and 1 patient each with grade 4 diarrhea and grade 3 hyponatremia. The most common grade 3 or 4 toxicities included diarrhea (50% of patients), nausea (16.6%), anorexia, and vomiting (11.1% each) (Table 1). There was no difference in frequencies of adverse events based on UGT1A1*28 status or prior opioid use (Table 1).

CONCLUSION

The clinical trial was terminated due to high frequency of unacceptable gastrointestinal toxicities, which precluded dose escalation of veliparib in combination with nal-IRI (ClinicalTrials.gov Identifier: NCT02631733).

A pilot project investigating the use of ONCOpatient®-An electronic patient-reported outcomes app for oncology patients

Purpose

To investigate the feasibility of implementing a remote patient monitoring system using an electronic patient-reported outcomes (ePROs) platform in a tertiary cancer center in the Republic of Ireland.

Methods

Patients receiving oral chemotherapy and oncology clinicians were invited to participate in the study. Patients were asked to submit weekly symptom questionnaires through an ePRO mobile phone application (app)-ONCOpatient®. Clinical staff were invited to use the ONCOpatient® clinician interface. After 8 weeks all participants submitted evaluation questionnaires.

Results

Thirteen patients and five staff were enrolled in the study. The majority of patients were female (85%) with a median age of 48 years (range 22-73). Most (92%) were enrolled over telephone requiring on average 16 minutes. Compliance with the weekly assessments was 91%. Alerts were triggered by 40% of patients who then required phone calls to aid with symptom management. At the end of study, 87% of patients reported they would use the app frequently, 75% reported that the platform met their expectations, and 25% that it exceeded their expectations. Similarly, 100% of staff reported they would use the app frequently, 60% reported that it met their expectations, and 40% that it exceeded their expectations.

Conclusions

Our pilot study showed that it is feasible to implement ePRO platforms in the Irish clinical setting. Small sample bias was recognized as a limitation, and we plan to confirm our findings on a larger cohort of patients. In the next phase we will integrate wearables including remote blood pressure monitoring.

A randomized phase 2 study of neoadjuvant carboplatin and paclitaxel with or without atezolizumab in triple negative breast cancer (TNBC) - NCI 10013

Atezolizumab with chemotherapy has shown improved progression-free and overall survival in patients with metastatic PD-L1 positive triple negative breast cancer (TNBC). Atezolizumab with anthracycline- and taxane-based neoadjuvant chemotherapy has also shown increased pathological complete response (pCR) rates in early TNBC. This trial evaluated neoadjuvant carboplatin and paclitaxel with or without atezolizumab in patients with clinical stages II-III TNBC. The co-primary objectives were to evaluate if chemotherapy and atezolizumab increase pCR rate and tumor infiltrating lymphocyte (TIL) percentage compared to chemotherapy alone in the mITT population. Sixty-seven patients (ages 25-78 years; median, 52 years) were randomly assigned - 22 patients to Arm A, and 45 to Arm B. Median follow up was 6.6 months. In the modified intent to treat population (all patients evaluable for the primary endpoints who received at least one dose of combination therapy), the pCR rate was 18.8% (95% CI 4.0-45.6%) in Arm A, and 55.6% (95% CI 40.0-70.4%) in Arm B (estimated treatment difference: 36.8%, 95% CI 8.5-56.6%; p = 0.018). Grade 3 or higher treatment-related adverse events occurred in 62.5% of patients in Arm A, and 57.8% of patients in Arm B. One patient in Arm B died from recurrent disease during the follow-up period. TIL percentage increased slightly from baseline to cycle 1 in both Arm A (mean ± SD: 0.6% ± 21.0%) and Arm B (5.7% ± 15.8%) (p = 0.36). Patients with pCR had higher median TIL percentages (24.8%) than those with non-pCR (14.2%) (p = 0.02). Although subgroup analyses were limited by the small sample size, PD-L1-positive patients treated with chemotherapy and atezolizumab had a pCR rate of 75% (12/16). The addition of atezolizumab to neoadjuvant carboplatin and paclitaxel resulted in a statistically significant and clinically relevant increased pCR rate in patients with clinical stages II and III TNBC. (Funded by National Cancer Institute).

Automated lesion detection of breast cancer in [18F] FDG PET/CT using a novel AI-Based workflow

Applications based on artificial intelligence (AI) and deep learning (DL) are rapidly being developed to assist in the detection and characterization of lesions on medical images. In this study, we developed and examined an image-processing workflow that incorporates both traditional image processing with AI technology and utilizes a standards-based approach for disease identification and quantitation to segment and classify tissue within a whole-body [18F]FDG PET/CT study.

METHODS

One hundred thirty baseline PET/CT studies from two multi-institutional preoperative clinical trials in early-stage breast cancer were semi-automatically segmented using techniques based on PERCIST v1.0 thresholds and the individual segmentations classified as to tissue type by an experienced nuclear medicine physician. These classifications were then used to train a convolutional neural network (CNN) to automatically accomplish the same tasks.

RESULTS

Our CNN-based workflow demonstrated Sensitivity at detecting disease (either primary lesion or lymphadenopathy) of 0.96 (95% CI [0.9, 1.0], 99% CI [0.87,1.00]), Specificity of 1.00 (95% CI [1.0,1.0], 99% CI [1.0,1.0]), DICE score of 0.94 (95% CI [0.89, 0.99], 99% CI [0.86, 1.00]), and Jaccard score of 0.89 (95% CI [0.80, 0.98], 99% CI [0.74, 1.00]).

CONCLUSION

This pilot work has demonstrated the ability of AI-based workflow using DL-CNNs to specifically identify breast cancer tissue as determined by [18F]FDG avidity in a PET/CT study. The high sensitivity and specificity of the network supports the idea that AI can be trained to recognize specific tissue signatures, both normal and disease, in molecular imaging studies using radiopharmaceuticals. Future work will explore the applicability of these techniques to other disease types and alternative radiotracers, as well as explore the accuracy of fully automated and quantitative detection and response assessment.

The Women's Health Initiative cancer survivorship clinic incorporating electronic patient-reported outcomes: a study protocol for the Linking You to Support and Advice (LYSA) randomized controlled trial

BACKGROUND

The improved survival rate for many cancers in high-income countries demands a coordinated multidisciplinary approach to survivorship care and service provision to ensure optimal patient outcomes and quality of life. This study assesses the feasibility of introducing a Women's Health Initiative cancer survivorship clinic in Ireland.

METHODS

The trial https://spcare.bmj.com/content/9/2/209.short comprises an intervention and control arm. Two hundred participants will be recruited. Key eligibility (1) women with early-stage hormone receptor-positive breast or gynecologic cancer (cervix or endometrial), within 12 months of completion of primary curative therapy, and (2) access to the Internet. The complex intervention comprises a nurse-led clinic targeting symptom management through a trigger alert system, utilizing electronic patient-reported outcome (ePRO) assessments at baseline, and 2, 4, 6, 8, 10, and 12 months. It also includes input from a dietitian monitoring diet and nutritional status. The control group will receive their usual care pathway standard of care and attend the cancer survivorship clinic and complete ePRO assessments at the start and end of the study. The primary endpoint (feasibility) includes the proportion of enrolled participants who complete baseline and follow-up ePRO surveys and partake in health professional consultations after ePRO data triggers. Secondary endpoints include changes in cancer-related symptom scores assessed by ePROs, health-related Quality of Life Questionnaire (QLQ) scores, Appraisal Self-Care Agency-R scores, and adjuvant endocrine therapy medication adherence. A process evaluation will capture the experiences of participation in the study, and the healthcare costs will be examined as part of the economic analysis. Ethical approval was granted in December 2020, with accrual commencing in March 2021.

DISCUSSION

This protocol describes the implementation of a parallel arm randomized controlled trial (RCT) which examines the feasibility of delivering a Cancer Survivorship Clinic. The ePRO is an innovative symptom monitoring system which detects the treatment-related effects and provides individualized support for cancer survivors. The findings will provide direction for the implementation of future survivorship care.

TRIAL REGISTRATION

ClinicalTrials.gov , NCT05035173 . Retrospectively registered on September 5, 2021.

Exploring homologous recombination deficiency thresholds for predicting response to platinum-based treatment in triple negative breast cancer

525

Background: Homologous recombination deficiency (HRD) status can be used to identify patients who are eligible for treatment with DNA damaging agents. Using a 3-biomarker Genomic Instability Score (GIS) threshold of ≥42, studies have previously examined the association between HRD status and outcomes in patients with triple negative breast cancer (TNBC). However, evidence suggests that a GIS threshold of ≥33 may be more appropriate. Here, we conducted an exploratory analysis evaluating the ability of ≥33 and ≥42 GIS thresholds to predict response to platinum-based treatment in patients with TNBC. Methods: Patients across 5 cohorts (TBCRC0301, TBCRC0082, NCT013725793, PrECOG 01054, combined cisplatin cohort4) were included in this analysis if they had a primary TNBC diagnosis, received neoadjuvant platinum-based treatment, had a valid GIS, and had known pathologic complete response (pCR) status. GIS was determined by a combination of loss of heterozygosity, telomeric-allelic imbalance, and large-scale state transitions.4,5 BRCA mutation status was defined by loss of function resulting from a pathogenic variant in BRCA1 or BRCA2. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV), were calculated by comparing binary threshold status and binary pCR status. Results: A total of 204 tumors (158 BRCAwt; 33 BRCAm; 13 unknown) were included; pCR to platinum-based treatment occurred in 55 cases (39 BRCAwt; 14 BRCAm; 2 unknown). Sensitivity, specificity, PPV, and NPV were comparable between the ≥33 and ≥42 GIS thresholds, with the ≥33 threshold producing higher sensitivity values. This was true when thresholds were applied to all samples and to BRCAwt samples only (Table). Among patients who achieved pCR in response to platinum-based treatment, 5.5% of patients in the full cohort and 7.7% of those in the BRCAwt cohort had a GIS between 33-41. Conclusions: To ensure that the majority of patients likely to benefit from treatment are identified, a GIS of ≥33 may be the most appropriate threshold to predict response to platinum-based treatment in patients with TNBC; however, a prospective trial will be needed to confirm these findings. Additional studies will be important to determine whether this threshold may be appropriate to determine eligibility for other DNA-damaging agents such as PARP inhibitors. 1. Ann Oncol. 2020;31(11):1518-25 2. J Nucl Med. 2015;56(1):31-7. 3. Breast Cancer Res Treat. 2015;151(3):629-38. 4. Clin Cancer Res. 2016;22(15):3764-73. 5. Breast Cancer Res Treat. 2014;16(6):1-9. [Table: see text]

The impact of COVID-19 on the performance of the Rapid Access Lung Clinic: The Cork/Kerry experience

e20542

Background: The COVID-19 pandemic has contributed to lower hospital admissions and higher mortalities associated with chronic conditions such as cancer and cardiovascular diseases. The Rapid Access Lung Clinic (RALC), established in 2009 for immediate assessment of individuals at risk of lung cancer, has experienced reduced functioning particularly during the pandemic peaks in Ireland. Therefore, we undertook a retrospective chart review of the 2019-2021 referrals and attendances at the Cork University Hospital (CUH) RALC to determine the impact of COVID-19 on this pathway. Methods: The medical charts of patients referred to CUH RALC from 03/2019 to 02/2020 (period I), and from 03/2020 to 02/2021 (period II), were reviewed after ethical approval was obtained. Clinicodemographic characteristics including age, sex, and hometown were extracted. Average time to acquire the first CT scan, consultation at RALC, and receiving a diagnosis of cancer were calculated using the date of referral and compared between periods I and II using the t-test. Frequency and the stages of cancer diagnosis in periods I and II were compared using a Chi-squared test. Progression-free and overall survivals were measured from diagnosis date until 09/2020 for period I and 09/2021 for period II. Results: Of the 1192 medical charts reviewed; 687 patients in period I and 505 patients in period II were referred to RALC; indicating a 26.5% reduction in the number of referrals during the first year of the pandemic. Average monthly referrals (p = 0.008) and reviews (p = 0.017) were significantly lower in period II compared to period I and corresponded with the COVID-19 peaks in 04/2020 and 01/2021 in Ireland. However, no significant difference was seen in the length of time from referral to review at RALC (p = 0.11). There were 33% fewer post-referral CT scans performed (p = 0.032) and shorter wait times from referral to CT scan in period II (p = 0.001). The frequency of cancers detected did not differ between periods I and II. While there was no difference in the wait times from referral to diagnosis between periods, patients ultimately diagnosed with lung cancer in period II received surgery sooner than patients in period I (p = 0.024). Progression-free and overall survivals for patients diagnosed with lung cancer were comparable between periods I and II. Conclusions: Contrary to our hypothesis, we have shown that the COVID-19 pandemic had minimal impact on the performance of RALC. Shorter wait times for CT scan and surgery during the pandemic account for fewer hospital referrals and availability of CT scanner. Fewer referrals to RALC in period II may relate to the fewer patients attending their general practitioner (GP) and/or GPs raising the thresholds for referrals to RALC during the pandemic. Ultimately, a national evaluation will be required to fully determine the impact of this pandemic on lung cancer diagnosis, management, and outcomes in Ireland.

The impact of a ransomware cyber attack on a breast cancer center

e13620

Background: On the 14th of May 2021 the Irish Health Service Executive (HSE) was the victim of a “Conti” ransomware attack. The HSE is a nationwide organization providing Ireland’s public health service, consisting of approximately 4000 locations and more than 70,000 connected devices. The study aim is to quantify the impact of the cyber attack by examining the effect on the Breast Cancer services at Cork University Hospital 1 of 8 national cancer centres & 1 of 54 HSE acute hospitals. Methods: New patient referrals through the weekly Breast cancer MDT meeting were used as the study nidus. Patient referrals & key performance indexes for a period of 4 weeks prior, during & after the attack were examined. Time was the key metric examined. Results: The attack triggered a Critical Incident Protocol, resulting in the switching off of all HSE IT systems at national level. Disruption to patient care & operations within the HSE was immediate & without warning. Initially encrypted messaging groups were established to facilitate communication & paper based tracking & data management logs were created. Diagnostics, scheduling & radiotherapy services were most severely affected. The attack resulted in the immediate shut down of the hospitals radiotherapy department with all new treatments transferred off site to a private facility, ongoing treatments delayed, replanned or rescheduled. The effect on the radiology department was catastrophic, all outpatient & non-urgent scans were cancelled. Digital report & image stores were unavailable. Historic imaging & ongoing emergency imaging was unavailable. Taking 7 months to restore impacted data storage & to ensure accurate capture of all reports for examinations during the cyber downtime. The average time from surgery to completed pathology went from 7.04 to 15.03 & 11.8 days in the 4 weeks prior, during & after the attack respectively. Services that were least impacted during the IT outage were those that relied on paper records including chemotherapy administration. The average time from biopsy report to up front surgery decreased from 21.75 to 17 & 14 days in the 4 weeks prior, during & after the attack respectively. Likely due to the increased availability of theatre time, as all non cancer related elective procedures were cancelled. There was little effect on the time from MDT discussion to review by medical oncology, taking an average of 6, 5.7 & 5.8 days in the 4 weeks prior, during & after the attack respectively. The majority of new referrals to the service being seen off site in a satellite clinic & infusion unit that relied on a paper based booking system prior to the attack. Conclusions: The cyber attack had significant disruptive effects lasting months. The impact on patient outcome due to delayed or interrupted treatment will take years to clarify. The attack was facilitated by the presence of multiple, fragmented IT platforms & demonstrated a lack of preparedness in the system which needs to be addressed to prevent recurrence.

The SARS-CoV-2 Pandemic and Cancer Trials Ireland: Impact, Resolution and Legacy

BACKGROUND

Cancer Trials Ireland (CTI) is the national cooperative group in Ireland. The SARS-CoV-2 pandemic led to significant ongoing disruptive change in healthcare from March 2020 to the present day. Its impact and legacy on a national clinical trials organisation was assessed.

METHODS

A review was conducted of prospectively acquired communications, team logs and time sheets, trial activation, closure and accrual, for the period 2019 to September 2021. An online survey of the impact of the pandemic on clinical investigators and of clinical trials units was performed. A National Cancer Retreat was organised on 21 May 2021 to identify and address pandemic related disruption and develop adaptive strategies.

RESULTS

In the weeks after the pandemic was declared, remote working was initiated by all central office staff. Nationally, clinical trial accrual fell by 54% compared to the same period in 2019, radiotherapy trial accrual by 90%, and translational studies by 36%. Staff reassignment of research nurse staff occurred in 60% of units, trial monitoring was reduced in 42%, and trial initiations fell by 67%. Extreme fluctuations in monitoring hours were noted paralleling lockdown measures. Significant impact on all clinical trials units was noted including staff reassignments, reduced access to diagnostic imaging and reduced institutional supports. Remote clinic visits and remote monitoring was widely adopted. The National Cancer Retreat identified flexibility in trial conduct, staff recruitment and retention, the need for harmonisation of processes, and research staff support in the context of remote working as priorities.

CONCLUSION

The pandemic has had a significant ongoing negative impact on cancer clinical trial activity in Ireland. Adaptive strategies including trial flexibility, expanded telehealth and remote monitoring, harmonisation of processes and staff support have been identified as priorities to ameliorate this impact, and develop a more sustainable clinical trial ecosystem.

Entinostat decreases immune suppression to promote anti-tumor responses in a HER2+ breast tumor microenvironment

Therapeutic combinations to alter immunosuppressive, solid tumor microenvironments (TMEs), such as in breast cancer, are essential to improve responses to immune checkpoint inhibitors (ICIs). Entinostat, an oral histone deacetylase inhibitor (HDACi), has been shown to improve responses to ICIs in various tumor models with immunosuppressive TMEs. The precise and comprehensive alterations to the TME induced by entinostat remain unknown. Here, we employed single-cell RNA-sequencing on HER2-overexpressing breast tumors from mice treated with entinostat and ICIs in order to fully characterize changes across multiple cell types within the TME. This analysis demonstrates that treatment with entinostat induced a shift from a pro-tumor to an anti-tumor TME signature, characterized predominantly by changes in myeloid cells. We confirmed myeloid-derived suppressor cells (MDSCs) within entinostat-treated tumors associated with a less suppressive granulocytic (G)-MDSC phenotype and exhibited altered suppressive signaling that involved the NFkB and STAT3 pathways. In addition to MDSCs, tumor-associated macrophages were epigenetically reprogrammed from a pro-tumor M2-like phenotype toward an anti-tumor M1-like phenotype, which may be contributing to a more sensitized TME. Overall, our in-depth analysis suggests that entinostat-induced changes on multiple myeloid cell types reduce immunosuppression and increase anti-tumor responses, which, in turn, improve sensitivity to ICIs. Sensitization of the TME by entinostat could ultimately broaden the population of patients with breast cancer who could benefit from ICIs.

Abstract P5-13-09: Identifying homologous recombination deficiency in breast cancer: Genomic instability score thresholds differ in breast cancer subtypes

Background: Patients with homologous recombin ation (HR) deficient tumors may benefit from treatment with DNA damaging agents. Markers of genomic instability can be used to identify HR deficiency, including a 3-biomarker Genomic Instability Score (GIS). For patients with ovarian cancer (OC), the FDA-approved GIS threshold for identifying HR deficiency is 42, set as the 5th percentile for BRCA deficient tumors. Recently, a lower 1st percentile cutoff of 33 was explored in OC; this threshold was significantly associated with improved outcome after platinum-based treatment.1,2 Determining an optimal GIS threshold for different types of tumors is crucial, as the GIS distribution may vary between different cancers and even between different cancer subtypes. We propose GIS thresholds for breast cancer separately for triple-negative breast cancer (TNBC) and estrogen receptor-positive (ER+) breast cancer, using the exploratory threshold of 33 for OC as a comparator. Methods: GISs in BRCA deficient tumors were determined for patients newly diagnosed with varying stages of OC, TNBC, or ER+ breast cancer across 5 cohorts (Timms et al,3 TCGA,4 Abkevich et al,5 TBCRC008,6 the OlympiaD trial7). GIS was determined as a combination of loss of heterozygosity, telomeric-allelic imbalance, and large-scale state transitions. BRCA deficiency was defined by loss of function resulting from a pathogenic variant in BRCA1 or BRCA2 or by methylation of the BRCA1 promoter region, with loss of heterozygosity in the affected gene. GIS distributions in different cancer types and subtypes were compared using the Kolmogorov-Smirnov test. A normal distribution was fit to GISs in BRCA deficient ER+ breast tumors. The 1st percentile of the fitted distribution was chosen as the threshold. Results: A total of 561 OC tumors (190 BRCA deficient), 99 TNBC tumors (44 BRCA deficient), and 406 ER+ breast tumors (76 BRCA deficient) were included across the 5 cohorts. When score distributions were evaluated for BRCA deficient tumors, the GIS distribution within ER+ breast cancer was significantly different than for OC (p=9.6x10-5) and TNBC (p=3.2x10-4). This indicates that different GIS thresholds are appropriate for breast cancer subtypes and that the GIS threshold developed for OC is not appropriate for ER+ breast cancer. The 1st percentile of a normal distribution fit in BRCA deficient ER+ breast cancer tumors yields a threshold of 24. Using this threshold, 45.1% (183/406; 75 BRCA deficient, 108 BRCA intact) of ER+ breast tumors were HR deficient. In contrast, the GIS distribution for TNBC was not significantly different than for OC (p=0.77). Using the exploratory threshold of 33, 63.6% (63/99; 44 BRCA deficient, 19 BRCA intact) of TNBC tumors were HR deficient. Conclusions: When compared to OC, the distribution of GIS in BRCA deficient tumors was different for ER+ breast cancer, but not for TNBC. These findings are consistent with the fact that OC and TNBC are known to have similar molecular signatures.8 Exploratory thresholds of 24 for ER+ breast cancer, and 33 for TNBC and OC could be examined to determine if these cutoffs are associated with a benefit from treatment with DNA targeting agents. Clinical validity and utility of these more inclusive 1% thresholds would require demonstration of correlation with clinical outcomes. The threshold difference observed between these cancer subtypes also suggests that cancer or cancer subtype specific thresholds may be needed as evaluations of HR deficiency expands beyond OC to identify candidates for PARP inhibitors. References: 1 Mol Cancer Res. 2018;16(7):1103-11. 2 Cancers. 2021;13(5):946. 3 Br J Cancer. 2012;107(10):1776-82. 4 Nature. 2012;490(7418):61-70. 5 Breast Cancer Res. 2014;16(145):1-9. 6 J Nucl Med. 2015;56(1):31-7. 7 NEJM. 2017;377(17):1700. 8 Int J Mol Sci. 2016;17(5):759.

Citation Format: Kirsten M Timms, Lauren Lenz, Chris Neff, Cara Solimeno, Darl Flake, Judy C Boughey, Matthew P Goetz, Andrea Richardson, Anna Maria Storniolo, Alexander Gutin, Roisin M Connolly, Vered Stearns, Jerry S Lanchbury. Identifying homologous recombination deficiency in breast cancer: Genomic instability score thresholds differ in breast cancer subtypes [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 P5-13-09.

Phase I Study of Entinostat and Nivolumab with or without Ipilimumab in Advanced Solid Tumors (ETCTN-9844)

PURPOSE

Epigenetic modulators improve immune checkpoint inhibitor (ICI) efficacy and increase CD8+ effector:FoxP3+ regulatory T cell ratios in preclinical models. We conducted a multicenter phase I clinical trial combining the histone deacetylase inhibitor entinostat with nivolumab ± ipilimumab in advanced solid tumors.

PATIENTS AND METHODS

Patients received an entinostat run-in (5 mg, weekly × 2) prior to the addition of ICIs. Dose escalation followed a modified 3+3 design [dose level (DL)1/2: entinostat + nivolumab; DL 3/4: entinostat + nivolumab + ipilimumab]. Blood and tissue samples were collected at baseline, after entinostat run-in, and after 8 weeks of combination therapy. Primary endpoints included safety and tolerability, and the recommended phase II dose (RP2D). Secondary endpoints included antitumor activity and change in tumor CD8/FoxP3 ratio pre- and post-therapy.

RESULTS

Thirty-three patients were treated across four dose levels. Treatment-related adverse events (AE) included fatigue (65%), nausea (41%), anemia (38%), diarrhea (26%), and anorexia (26%). Grade 3/4 AEs included fatigue (n = 7, 21%), anemia (n = 9, 27%), and neutropenia (n = 4, 12%). The RP2D was 3 mg entinostat weekly, 3 mg/kg every 2 weeks nivolumab, and 1 mg/kg every 6 weeks ipilimumab (max four doses). The objective response rate by RECIST 1.1 was 16%, including a complete response in triple-negative breast cancer. A statistically significant increase in CD8/FoxP3 ratio was seen following the addition of ICIs to entinostat, but not post-entinostat alone.

CONCLUSIONS

The combination of entinostat with nivolumab ± ipilimumab was safe and tolerable with expected rates of immune-related AEs. Preliminary evidence of both clinical efficacy and immune modulation supports further investigation.

A Multicenter Phase II Trial of Ipilimumab and Nivolumab in Unresectable or Metastatic Metaplastic Breast Cancer: Cohort 36 of Dual Anti-CTLA-4 and Anti-PD-1 Blockade in Rare Tumors (DART, SWOG S1609)

PURPOSE

Metaplastic breast cancer (MpBC) is a rare aggressive subtype that responds poorly to cytotoxics. Median survival is approximately eight months for metastatic disease. We report results for advanced MpBC treated with ipilimumab+nivolumab, a cohort of S1609 for rare cancers (DART: NCT02834013).

METHODS

Prospective, open-label, multicenter phase II (two-stage) trial of ipilimumab (1mg/kg IV q6weeks) plus nivolumab (240mg IV q2weeks) for advanced MpBC. Primary endpoint was objective response rate (ORR). Secondary endpoints included progression-free survival (PFS), overall survival (OS) and toxicity.

RESULTS

Overall, 17 evaluable patients enrolled. Median age was 60 years (26-85); median number of prior therapy lines, 2 (0-5). ORR was 18%; 3/17 patients achieved objective responses (1 complete, 2 partial responses) (2 spindle cell, 1 chondromyxoid histology), which are ongoing at 28+, 33+ and 34+ months, respectively. Median PFS and OS were 2 and 12 months, respectively. Altogether, 11 patients (65%) experienced adverse events (AEs), including one grade 5 AE. Eight patients (47%) developed an immune-related AE (irAE); with adrenal insufficiency observed in all three responders. Responses occurred in tumors with low tumor mutational burden, low PD-L1 and absent TILs.

CONCLUSION

The ipilimumab and nivolumab combination showed no new safety signals and met its primary endpoint with 18% ORR in advanced, chemotherapy-refractory MpBC. All responses are ongoing at >2 to almost 3 years later. The effect of ipilimumab and nivolumab was associated with exceptional responses in a subset of patients versus no activity. This combination warrants further investigation in MpBC, with special attention to understanding mechanism of action, and carefully designed to weigh against the significant risks of irAEs.

E2112: Randomized Phase III Trial of Endocrine Therapy Plus Entinostat or Placebo in Hormone Receptor-Positive Advanced Breast Cancer. A Trial of the ECOG-ACRIN Cancer Research Group

PURPOSE

Endocrine therapy resistance in advanced breast cancer remains a significant clinical problem that may be overcome with the use of histone deacetylase inhibitors such as entinostat. The ENCORE301 phase II study reported improvement in progression-free survival (PFS) and overall survival (OS) with the addition of entinostat to the steroidal aromatase inhibitor (AI) exemestane in advanced hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative breast cancer.

PATIENTS AND METHODS

E2112 is a multicenter, randomized, double-blind, placebo-controlled phase III study that enrolled men or women with advanced HR-positive, HER2-negative breast cancer whose disease progressed after nonsteroidal AI. Participants were randomly assigned to exemestane 25 mg by mouth once daily and entinostat (EE) or placebo (EP) 5 mg by mouth once weekly. Primary end points were PFS by central review and OS. Secondary end points included safety, objective response rate, and lysine acetylation change in peripheral blood mononuclear cells between baseline and cycle 1 day 15.

RESULTS

Six hundred eight patients were randomly assigned during March 2014-October 2018. Median age was 63 years (range 29-91), 60% had visceral disease, and 84% had progressed after nonsteroidal AI in metastatic setting. Previous treatments included chemotherapy (60%), fulvestrant (30%), and cyclin-dependent kinase inhibitor (35%). Most common grade 3 and 4 adverse events in the EE arm included neutropenia (20%), hypophosphatemia (14%), anemia (8%), leukopenia (6%), fatigue (4%), diarrhea (4%), and thrombocytopenia (3%). Median PFS was 3.3 months (EE) versus 3.1 months (EP; hazard ratio = 0.87; 95% CI, 0.67 to 1.13; P = .30). Median OS was 23.4 months (EE) versus 21.7 months (EP; hazard ratio = 0.99; 95% CI, 0.82 to 1.21; P = .94). Objective response rate was 5.8% (EE) and 5.6% (EP). Pharmacodynamic analysis confirmed target inhibition in entinostat-treated patients.

CONCLUSION

The combination of exemestane and entinostat did not improve survival in AI-resistant advanced HR-positive, HER2-negative breast cancer.

Pembrolizumab for patients with leptomeningeal metastasis from solid tumors: efficacy, safety, and cerebrospinal fluid biomarkers

Background

The benefit of immune checkpoint inhibitors (ICIs) in patients with leptomeningeal metastases (LMM) is unknown.

Methods

We undertook a phase II trial of pembrolizumab in patients with LMM from solid tumors. Eligible patients had radiologic/cytologic LMM and Eastern Cooperative Oncology Group performance status 0–1. Pembrolizumab was administered intravenously at 200 mg q3W until disease progression/unacceptable toxicity. The primary endpoint was central nervous system (CNS) response after four cycles, defined radiologically/cytologically/clinically. Serial cerebrospinal fluid (CSF) was assessed for tumor-derived DNA (t-DNA) aneuploidy and cytokines.

Results

Thirteen of a planned 16 patients were treated between April 2017 and December 2019. The study closed early for poor accrual. Median age was 57 years (range: 22–79). Sixty-two percent of patients had tumors not traditionally ICI-responsive (hormone-receptor (HR)-positive breast carcinoma=39%; high-grade glioma=23%), while 38% had ICI-responsive tumors (non-small cell lung cancer (NSCLC)=23%, head and neck carcinoma=8%, cutaneous squamous carcinoma (CSC)=8%). CNS response was observed in 38% of patients at 12 weeks (95% CI 13.9% to 68.4%) by pre-defined criteria and LM-RANO, and 2 achieved durable complete responses (CSC=1, overall survival (OS) 3+ years; NSCLC=1, OS 9 months). Median CNS progression-free survival and OS was 2.9 months (95% CI 1.3 to NR) and 4.9 months (95% CI 3.7 to NR), respectively. Grade 3+ treatment-related adverse events occurred in 15% of patients. Sensitivity for LMM detection by t-DNA and cytopathology was 84.6% (95% CI 54.6% to 98.1%) and 53.9% (95% CI 25.1% to 80.8%), respectively. Pre-therapy and on-therapy CSF cytokine analysis demonstrated complete responders clustered together.

Conclusions

Pembrolizumab conferred a 38% CNS response rate in patients with LMM, a tolerable safety profile, and deep responses in selected patients with ICI-responsive tumors. CSF t-DNA may be sensitive for LMM detection, and immunologic subsets of CNS response warrant further study.

Trial registration number

NCT03091478

Updated Results of TBCRC026: Phase II Trial Correlating Standardized Uptake Value With Pathological Complete Response to Pertuzumab and Trastuzumab in Breast Cancer

PURPOSE

Predictive biomarkers to identify patients with human epidermal growth factor receptor 2 (HER2)-positive breast cancer who may benefit from targeted therapy alone are required. We hypothesized that early measurements of tumor maximum standardized uptake value corrected for lean body mass (SULmax) on 18F-labeled fluorodeoxyglucose positron emission tomography-computed tomography (PET-CT) would predict pathologic complete response (pCR) to pertuzumab and trastuzumab (PT).

PATIENTS AND METHODS

Patients with stage II or III, estrogen receptor-negative, HER2-positive breast cancer received four cycles of neoadjuvant PT. 18F-labeled fluorodeoxyglucose positron emission tomography-computed tomography was performed at baseline and 15 days after PT initiation (C1D15). Eighty evaluable patients were required to test the null hypothesis that the area under the curve of percent change in SULmax by C1D15 predicting pCR is ≤ 0.65, with a one-sided type I error rate of 10%.

RESULTS

Eighty-eight women were enrolled (83 evaluable), and 85% (75 of 88) completed all four cycles of PT. pCR after PT alone was 22%. Receiver operator characteristic analysis of percent change in SULmax by C1D15 yielded an area under the curve of 0.72 (80% CI, 0.64 to 0.80; one-sided P = .12), which did not reject the null hypothesis. However, between patients who obtained pCR and who did not, a significant difference in median percent reduction in SULmax by C1D15 was observed (63.8% v 41.8%; P = .004) and SULmax reduction ≥ 40% was more prevalent (83% v 52%; P = .03; positive predictive value, 31%). Participants not obtaining a 40% reduction in SULmax by C1D15 were unlikely to obtain pCR (negative predictive value, 91%).

CONCLUSION

Although the primary objective was not met, early changes in SULmax predict response to PT in estrogen receptor-negative and HER2-positive breast cancer. Once optimized, this quantitative imaging strategy may facilitate tailoring of therapy in this setting.

Phase 1 study of single-agent WNT974, a first-in-class Porcupine inhibitor, in patients with advanced solid tumours

BACKGROUND

This Phase 1 study assessed the safety and efficacy of the Porcupine inhibitor, WNT974, in patients with advanced solid tumours.

METHODS

Patients (n = 94) received oral WNT974 at doses of 5-30 mg once-daily, plus additional dosing schedules.

RESULTS

The maximum tolerated dose was not established; the recommended dose for expansion was 10 mg once-daily. Dysgeusia was the most common adverse event (50% of patients), likely resulting from on-target Wnt pathway inhibition. No responses were seen by Response Evaluation Criteria in Solid Tumors (RECIST) v1.1; 16% of patients had stable disease (median duration 19.9 weeks). AXIN2 expression by RT-PCR was reduced in 94% of paired skin biopsies (n = 52) and 74% of paired tumour biopsies (n = 35), confirming inhibition of the Wnt pathway. In an exploratory analysis, an inverse association was observed between AXIN2 change and immune signature change in paired tumour samples (n = 8).

CONCLUSIONS

Single-agent WNT974 treatment was generally well tolerated. Biomarker analyses suggest that WNT974 may influence immune cell recruitment to tumours, and may enhance checkpoint inhibitor activity.

CLINICAL TRIAL REGISTRATION

NCT01351103.

Invasive breast Cancer treatment in Tanzania: landscape assessment to prepare for implementation of standardized treatment guidelines

BACKGROUND

Incidence of breast cancer continues to rise in low- and middle-income countries, with data from the East African country of Tanzania predicting an 82% increase in breast cancer from 2017 to 2030. We aimed to characterize treatment pathways, receipt of therapies, and identify high-value interventions to increase concordance with international guidelines and avert unnecessary breast cancer deaths.

METHODS

Primary data were extracted from medical charts of patients presenting to Bugando Medical Center, Tanzania, with breast concerns and suspected to have breast cancer. Clinicopathologic features were summarized with descriptive statistics. A Poisson model was utilized to estimate prevalence ratios for variables predicted to affect receipt of life-saving adjuvant therapies and completion of therapies. International and Tanzanian guidelines were compared to current care patterns in the domains of lymph node evaluation, metastases evaluation, histopathological diagnosis, and receptor testing to yield concordance scores and suggest future areas of focus.

RESULTS

We identified 164 patients treated for suspected breast cancer from April 2015-January 2019. Women were predominantly post-menopausal (43%) and without documented insurance (70%). Those with a confirmed histopathology diagnosis (69%) were 3 times more likely to receive adjuvant therapy (PrR [95% CI]: 3.0 [1.7-5.4]) and those documented to have insurance were 1.8 times more likely to complete adjuvant therapy (1.8 [1.0-3.2]). Out of 164 patients, 4% (n = 7) received concordant care based on the four evaluated management domains. The first most common reason for non-concordance was lack of hormone receptor testing as 91% (n = 144) of cases did not undergo this testing. The next reason was lack of lymph node evaluation (44% without axillary staging) followed by absence of abdominopelvic imaging in those with symptoms (35%) and lack of histopathological confirmation (31%).

CONCLUSIONS

Patient-specific clinical data from Tanzania show limitations of current breast cancer management including axillary staging, receipt of formal diagnosis, lack of predictive biomarker testing, and low rates of adjuvant therapy completion. These findings highlight the need to adapt and adopt interventions to increase concordance with guidelines including improving capacity for pathology, developing complete staging pathways, and ensuring completion of prescribed adjuvant therapies.

Abstract PD14-09: Nci 10013 - A randomized phase 2 study of neoadjuvant carboplatin and paclitaxel, with or without atezolizumab in triple negative breast cancer (TNBC)

Background Inhibition of PD-L1 with atezolizumab combined with chemotherapy has shown acceptable safety and improved survival in patients with metastatic PD-L1 positive triple negative breast cancer (TNBC). Patients with TNBC who do not achieve a pathological complete response (pCR) to neoadjuvant chemotherapy have a high risk of disease recurrence and death. This randomized, open-label, phase 2 trial evaluates neoadjuvant carboplatin and paclitaxel with or without atezolizumab in patients with previously untreated clinical stages II and III TNBC. Methods Women aged ≥18 years with clinical stage T2-T4c, any N, M0 primary tumor by AJCC 7th edition staging TNBC; ECOG PS 0-2; and no prior systemic therapy for the indexed breast cancer were eligible. Patients were randomized in a 1:2 ratio to carboplatin AUC5 q 3 weeks x 4 + paclitaxel 80 mg/m2 q week x 12 (Arm A), or carboplatin AUC5 q 3 weeks x 4 + paclitaxel 80 mg/m2 q week x 12 + atezolizumab 1200 mg q3 weeks x 4 (Arm B). Surgery was 3-6 weeks following neoadjuvant chemotherapy. Adjuvant dose-dense doxorubicin and cyclophosphamide was administered q2 weeks with growth factor support to all patients as per routine care. pCR and tumor infiltrating lymphocyte (TIL) percentages are the co-primary endpoints. pCR-evaluable population includes all eligible women who have been randomized and received at least one dose of combination therapy, while the TIL-evaluable population includes all eligible women who have evaluable TIL percentage after one cycle of therapy. A sample size of 67 (22 in Arm A, and 45 in Arm B) provided 80% power at 1-sided alpha = 0.10 to detect a minimum of 15% difference in TIL and 29% improvement (40% vs. 69%) in pCR, respectively. Herein, we report pCR results in the per protocol modified intent-to-treat population (mITT), which includes all eligible patients who were randomized and received at least one dose of combination therapy. Results Sixty-seven patients were randomized between 8/2017 and 9/2019. Six patients randomized to Arm A withdrew consent; 2 of these received protocol therapy but are excluded from the mITT analyses as they are not evaluable because definitive pathology reports are not available. Median follow up is 6 months (range 0.3 - 12.6 months). Median age is 52 years (range 25 - 78). Forty-three (64.2%) were Caucasian and thirteen (19.4%) were African American. Twenty-five (37.3%) were pre-menopausal. 67.2% and 32.8% had stages II and III disease respectively. Nine (13.4%) had a germline mutation in either BRCA1 or BRCA2. In the mITT population, 3 of 16 patients achieved pCR in Arm A - 18.8% (95% CI 4.0%- 45.6%), versus 25 of 45 patients in Arm B - 55.6% (95% CI 40.0%-70.4%); p value 0.018. pCR in those with BRCA mutations was 50% and 80% in Arm A and Arm B, respectively. Treatment delays were observed in 9 patients (40.9%) in Arm A, and 20 (44.4%) in Arm B; dose reductions occurred in 4 patients (18.1%) in Arm A, and in 6 (13.3%) in Arm B. There were 4 SAEs in Arm A and 10 in Arm B. One patient in Arm B had grade 3 adrenal insufficiency. One patient in Arm B died from recurrent disease during the follow-up period. Conclusions: The addition of atezolizumab to neoadjuvant carboplatin and paclitaxel resulted in an increased pCR rate in patients with clinical stages II and III TNBC. However, the pCR in the control Arm A was lower than expected, possibly due to the absence of neoadjuvant anthracyclines. The high pCR rate observed in the experimental arm of this study is similar to that observed in other neoadjuvant trials utilizing anthracyclines, taxanes, and carboplatin in TNBC. Clinical trial information: NCT02883062.

Citation Format: Foluso O Ademuyiwa, Feng Gao, Ina Chen, Donald W Northfelt, Robert Wesolowski, Mili Arora, Adam Brufsky, Claire Dees, Cesar A Santa-Maria, Roisin M Connolly, Jeremy Force, Alvaro Moreno-Aspitia, Sarah Larson, Elad Sharon, William Gillanders. Nci 10013 - A randomized phase 2 study of neoadjuvant carboplatin and paclitaxel, with or without atezolizumab in triple negative breast cancer (TNBC) [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PD14-09.

Abstract GS4-02: E2112: Randomized phase 3 trial of endocrine therapy plus entinostat/placebo in patients with hormone receptor-positive advanced breast cancer. A trial of the ECOG-ACRIN cancer research group

Background: Endocrine therapy resistance in advanced breast cancer remains a significant clinical problem that may be overcome with use of histone deacetylase (HDAC) inhibitors such as entinostat. The ENCORE 301 randomized phase II study reported an improvement in progression-free (PFS) and overall survival (OS) with the addition of entinostat to the steroidal aromatase inhibitor (AI) exemestane in patients with advanced hormone receptor (HR)-positive, HER2-negative breast cancer. Protein lysine acetylation in peripheral blood mononuclear cells (PBMCs) was associated with prolonged PFS in the entinostat arm.

Methods: E2112 is a multicenter randomized double-blind, placebo-controlled phase III study that enrolled men or women with advanced HR-positive, HER2-negative breast cancer whose disease had progressed on a non-steroidal AI in the adjuvant or metastatic setting (NCT02115282). Study participants were also required to have an ECOG performance status 0-1 with measurable or non-measurable (limited to 20% of the study population) disease. One prior chemotherapy for metastatic disease and prior treatment with fulvestrant and a CDK4/6 inhibitor was permitted but not required. Participants received exemestane 25mg po daily and entinostat (EE)/placebo (EP) 5mg po every week. Primary endpoints were PFS (central review) and OS. One-sided type 1 error 0.025 was split between two hypothesis tests: 0.001 for PFS test and 0.024 for OS. PFS tested in the first 360 pts, 88.5% power to detect 42% reduction in the hazard of PFS failure (median PFS, 4.1 to 7.1 months); OS tested in all 600 pts, 80% power to detect 25% reduction in the hazard of death (median OS, 22 to 29.3 months). Secondary endpoints included safety, objective response rate (ORR), and changes in protein lysine acetylation status in PBMCs (CD3+ T cells, CD14+ monocytes, CD19+ B cells, pan-leukocyte marker CD45+ cells, CD56+ NK cells) between C1D1 and C1D15 (integrated biomarker).

Results: A total of 608 participants were randomized between March 2014 and October 2018 (305 EE, 303 EP), 98% enrolled in USA. Characteristics were well balanced between the arms. Median age was 63 years (range, 29-91), 99% female, 95% postmenopausal, 80% white and 15% black. A majority (84%) had disease resistant to AI in the metastatic setting at study entry, 78% had measurable disease and 60% visceral disease. Prior treatments included chemotherapy (60%), fulvestrant (30%), CDK4/6 inhibitor (35%), everolimus (3%). Median prior lines of chemotherapy was 1 (range, 0-4) and endocrine therapy was 2 (range, 1-7); in adjuvant/metastatic setting. Grade 3/4 adverse events in EE arm included neutrophil count decreased (20%), hypophosphatemia (14%), anemia (8%), white blood cell decreased (6%), fatigue (4%), diarrhea (4%), and platelet count decreased (3%). At final analysis, median PFS was 3.3 months (EE) versus 3.1 months (EP) (HR=0.87, 95% CI: 0.67, 1.13, p=0.30). Median OS was 23.4 months (EE) versus 21.7 months (EP) (HR=0.99, 95% CI: 0.82, 1.21, p=0.94). ORR was 4.6% (EE) and 4.3% (EP). The median fold change in lysine acetylation in PBMCs was approximately 1.5 in EE arm, and 1 in EP arm. Participants on EE had significantly higher increase in lysine acetylation by C1D15 than patients on EP (397 paired samples available for analysis, p&lt;0.001 for all). Additional biomarker analyses will be presented at time of meeting.

Conclusion: The combination of exemestane and entinostat did not improve survival in AI resistant advanced HR-positive, HER2-negative breast cancer. Pharmacodynamic analysis confirmed target inhibition in entinostat-treated patients.

Citation Format: Roisin M Connolly, Fengmin Zhao, Kathy D Miller, Min-Jung Lee, Richard L Piekarz, Karen L Smith, Ursa Brown-Glaberman, Jennifer S Winn, Bryan A Faller, Adedayo A Onitilo, Mark E Burkard, George T Budd, Ellis G Levine, Melanie E Royce, Peter A Kaufman, Alexandra Thomas, Jane B Trepel, Antonio C Wolff, Joseph A Sparano. E2112: Randomized phase 3 trial of endocrine therapy plus entinostat/placebo in patients with hormone receptor-positive advanced breast cancer. A trial of the ECOG-ACRIN cancer research group [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr GS4-02.

A randomized intervention involving family to improve communication in breast cancer care

We examined the effects of a communication intervention to engage family care partners on patient portal (MyChart) use, illness understanding, satisfaction with cancer care, and symptoms of anxiety in a single-blind randomized trial of patients in treatment for breast cancer. Patient-family dyads were recruited and randomly assigned a self-administered checklist to clarify the care partner role, establish a shared visit agenda, and facilitate MyChart access (n = 63) or usual care (n = 55). Interviews administered at baseline, 3, 9 (primary endpoint), and 12 months assessed anxiety (GAD-2), mean FAMCARE satisfaction, and complete illness understanding (4 of 4 items correct). Time-stamped electronic interactions measured MyChart use. By 9 months, more intervention than control care partners registered for MyChart (77.8 % vs 1.8%; p < 0.001) and logged into the patient’s account (61.2% vs 0% of those registered; p < 0.001), but few sent messages to clinicians (6.1% vs 0%; p = 0.247). More intervention than control patients viewed clinical notes (60.3% vs 32.7%; p = 0.003). No pre-post group differences in patient or care partner symptoms of anxiety, satisfaction, or complete illness understanding were found. Intervention patients whose care partners logged into MyChart were more likely to have complete illness understanding at 9 months (changed 70.0% to 80.0% vs 69.7% to 54.6%; p = 0.03); symptoms of anxiety were numerically lower (16.7% to 6.7% vs 15.2% to 15.2%; p = 0.24) and satisfaction numerically higher (15.8–16.2 vs 18.0–17.4; p = 0.25). A brief, scalable communication intervention led to greater care partner MyChart use and increased illness understanding among patients with more engaged care partners (NCT03283553).

Phase I and Pharmacokinetic Study of Romidepsin in Patients with Cancer and Hepatic Dysfunction: A National Cancer Institute Organ Dysfunction Working Group Study

PURPOSE

Romidepsin dosing recommendations for patients with malignancy and varying degrees of hepatic dysfunction was lacking at the time of regulatory approval for T-cell lymphoma. We conducted a multicenter phase I clinical trial (ETCTN-9008) via the NCI Organ Dysfunction Working Group to investigate safety, first cycle MTD, and pharmacokinetic profile of romidepsin in this setting.

PATIENTS AND METHODS

Patients with select advanced solid tumors or hematologic malignancies were stratified according to hepatic function. Romidepsin was administered intravenously on days 1, 8, and 15 of a 28-day cycle and escalation followed a 3 + 3 design in moderate and severe impairment cohorts. Blood samples for detailed pharmacokinetic analyses were collected after the first dose.

RESULTS

Thirty-one patients received one dose of romidepsin and were evaluable for pharmacokinetic analyses in normal (n = 12), mild (n = 8), moderate (n = 5), and severe (n = 6) cohorts. Adverse events across cohorts were similar, and dose-limiting toxicity occurred in two patients (mild and severe impairment cohorts). The MTD was not determined because the geometric mean AUC values of romidepsin in moderate (7 mg/m²) and severe (5 mg/m²) impairment cohort were 114% and 116% of the normal cohort (14 mg/m²).

CONCLUSIONS

Data from the ETCTN-9008 trial led to changes in the romidepsin labeling to reflect starting dose adjustment for patients with cancer and moderate and severe hepatic impairment, with no adjustment for mild hepatic impairment.

Abstract 1555: Single cell level treatment-specific characterization of HER2+ breast cancers treated with immune checkpoint inhibitors and entinostat

HER2+ breast cancers are known to be less-immunogenic and associated with low response rates to ICIs such as anti-PD-1, anti-PDL-1 or anti-CTLA-4. A combination of immunosuppressive signals that prevent cytotoxic T cells from infiltrating the tumor microenvironment (TME) and low tumor antigen expression contribute to immunotherapy resistance in this population. Epigenetic modulators can both reexpress tumor antigens and rewire the immunosuppressive environment. We previously used a benzamide histone deacetylase inhibitor, entinostat, in combination with ICIs to reverse the immunosuppressive TME and increase tumor antigen expression in a NeuN HER2+ mouse model of breast cancer. Our results showed that entinostat in combination with anti-PD-1, anti-CTLA-4, or both provided a significant survival benefit compared to either treatment alone. This current study employs single cell RNA-seq on whole tumor samples from mice treated with ICIs and entinostat to investigate the role of epigenetic inhibitors in rewiring the expression of tumor antigens and the cellular landscape of the TME. We generate single cell data of over 54,000 cells from 20 tumors treated with entinostat alone or in combination with anti-PD-1 and anti-CTLA-4 and their combination. Analysis of cells in the TME identifies consistent proportion of monocytes, macrophages, T-cells, Myeloid Derived Suppressor Cells (MDSCs) and Cancer Associated Fibroblasts (CAFs) before and after treatment. Differential expression analysis within the cell types identifies distinct subpopulations and we explore those that are either proportionally higher or lower in each treatment group. Notably, pathway analysis on differentially expressed genes of each cell type identified that combination entinostat and checkpoint treatment increased T cell activation, leukocyte proliferation, myeloid leukocyte and neutrophil migration, and decreased Wnt signaling and histone modifications in tumor cells. Further analysis of the tumor cells from these data and additional ATAC-seq data will enable us to further test the role of antigen reexpression in this TME of activated tumors. We also used the CoGAPS matrix factorization algorithm and RNA velocity analysis to identify transcriptional patterns that are enriched in response to combination treatment. Our current work provides insights into the transcriptional network within a breast tumor after treatment with entinostat. Our follow-up studies in patient samples from a corresponding clinical trial will allow us to map the role of epigenetic modulation in breast tumors. We predict our findings will bring us closer to identifying additional therapeutic targets and ultimately improve survival rates of patients with less-immunogenic tumors. NCT02453620.

Citation Format: Dimitrios N. Sidiropoulos, Emily Davis-Marcisak, Christine Rafie, Luciane T. Kagohara, Gaurav Sharma, Roisin M. Connolly, Vered Stearns, Srinivasan Yegnasubramanian, Elizabeth M. Jaffee, Elana J. Fertig, Evanthia T. Roussos Torres. Single cell level treatment-specific characterization of HER2+ breast cancers treated with immune checkpoint inhibitors and entinostat [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1555.

Management of Breast Cancer During the COVID-19 Pandemic: A Stage- and Subtype-Specific Approach

The COVID-19 pandemic has rapidly changed delivery of cancer care. Many nonurgent surgeries are delayed to preserve hospital resources, and patient visits to health care settings are limited to reduce exposure to SARS-CoV-2. Providers must carefully weigh risks and benefits of delivering immunosuppressive therapy during the pandemic. For breast cancer, a key difference is increased use of neoadjuvant systemic therapy due to deferral of many breast surgeries during the pandemic. In some cases, this necessitates increased use of genomic tumor profiling on core biopsy specimens to guide neoadjuvant therapy decisions. Breast cancer treatment during the pandemic requires multidisciplinary input and varies according to stage, tumor biology, comorbidities, age, patient preferences, and available hospital resources. We present here the Johns Hopkins Women's Malignancies Program approach to breast cancer management during the COVID-19 pandemic. We include algorithms based on tumor biology and extent of disease that guide management decisions during the pandemic. These algorithms emphasize medical oncology treatment decisions and demonstrate how we have operationalized the general treatment recommendations during the pandemic proposed by national groups, such as the COVID-19 Pandemic Breast Cancer Consortium. Our recommendations can be adapted by other institutions and medical oncology practices in accordance with local conditions and resources. Guidelines such as these will be important as we continue to balance treatment of breast cancer against risk of SARS-CoV-2 exposure and infection until approval of a vaccine.

Trial in progress: A phase II open-label, randomized study of PARP inhibition (olaparib) either alone or in combination with anti-PD-L1 therapy (atezolizumab) in homologous DNA repair (HDR) deficient, locally advanced or metastatic non-HER2-positive breast cancer

TPS1102

Background: While immunostimulatory therapies have shown great success, a major challenge remains identification of mechanisms to effectively treat the majority of patients with so-called "non-inflamed" tumors lacking marked lymphocyte infiltration and PD-L1 expression. The DNA repair proficiency of a tumor may impact its potential for immune recognition and sensitivity to immune checkpoint blockade. Preclinically, PARP inhibition in HDR-deficient tumors has been shown to trigger antitumor immunity through a STING-dependent antitumor immune response. Effects of PARP inhibitors were augmented when combined with PD-1 blockade. We hypothesize that enhanced DNA damage and cell death induced by PARP inhibition in tumors with homology directed repair (HDR) deficiency will enhance adaptive anti-tumor immune responses and increase sensitivity to PD-1 axis blockers. Methods: This is a randomized, open-label phase II clinical trial exploring the PARP inhibitor olaparib either alone or in combination with the anti-PD-L1 human monoclonal antibody atezolizumab in BRCA1/2 mutated locally advanced or metastatic non-HER2-positive breast cancer. HDR deficiency is defined as the presence of deleterious BRCA 1/2 mutations. Randomization occurs in a 1:1 fashion to two arms: (1) olaparib 300 mg PO bid continuously in 21-day cycles or (2) olaparib 300 mg PO bid continuously in combination with atezolizumab 1200 IV every 3 weeks in 21-day cycles. Patients undergo baseline evaluations and pre-treatment biopsy within 2 weeks of starting therapy. Repeat biopsies are required at the time of first tumor assessment scan (6 weeks from the start of treatment) and in the event of disease progression. Correlative studies, including detailed analysis of the genomic profile and tumor immune contexture, will be performed at each biopsy time point. The primary objective is to compare progression free survival between the study arms. If progression occurs on the olaparib monotherapy arm, cross-over to the combination arm is allowed. This study began enrolling in August 2018; 47 of the planned 72 patients have been registered. Clinical trial information: NCT02849496 .

Characterization of the immune tumor microenvironment of HER2-positive breast cancer following treatment with entinostat and immune checkpoint inhibition

e15061

Background: HER2+ breast cancers are known to be less-immunogenic and associated with low response rates to immune checkpoint inhibitors (ICIs). A combination of immunosuppressive signals that prevent cytotoxic T cells from infiltrating the tumor microenvironment (TME) and, low tumor antigen expression, contribute to immunotherapy resistance in this population. Epigenetic modulators can both reexpress tumor antigens and rewire the immunosuppressive environment. We previously used a histone deacetylase inhibitor, entinostat (ENT), in combination with ICIs to reverse the immunosuppressive TME and increase tumor antigen expression in a NeuN HER2+ mouse model of breast cancer. Our results showed that ENT in combination with anti-PD-1, anti-CTLA-4, provided a significant survival benefit compared to either treatment alone. Methods: This current study employs single cell RNA-sequencing on whole tumor samples from mice treated with ICIs and entinostat to investigate the role of epigenetic inhibitors in rewiring the expression of tumor antigens and the cellular landscape of the TME. We generate single cell data over 54,000 cells from 20 tumors treated with entinostat alone or in combination with anti-PD1 and anti-CTLA4 and their combination. Results: Analysis of cells in the TME identifies consistent proportion of monocytes, macrophages, T-cells, Myeloid Derived Suppressor Cells (MDSCs) and Cancer Associated Fibroblasts (CAFs) before and after treatment. Differential expression analysis within the cell types identifies distinct subpopulations and we explore those that are either proportionally higher or lower in each treatment group. Notably, pathway analysis on differentially expressed genes of each cell type identified that combination entinostat and checkpoint treatment increased T cell activation, leukocyte proliferation, myeloid leukocyte and neutrophil migration, and decreased Wnt signaling and histone modifications in tumor cells. These results are being corroborated in patient samples from a parallel clinical trial to provide translational relevance. Conclusions: Our current work provides insights into the transcriptional network within a breast tumor after treatment with ENT+ICIs. We predict our findings will bring us closer to identifying additional therapeutic targets and ultimately improve survival rates of patients with less-immunogenic tumors.

Anti-PD-1 for patients with leptomeningeal metastasis from advanced solid tumors: Efficacy, safety, and biomarkers of response

e14506

Background: Leptomeningeal metastasis (LMM) from solid tumors are rare and often refractory to standard therapies. Pembrolizumab (anti-PD-1) has efficacy in patients (pts) with brain metastases from ICI-responsive tumors, however pts with LMM are often excluded from ICI trials. We hypothesized that: 1. Pembrolizumab will lead to CNS response in LMM, and 2. Genomic/immunologic analyses on CSF could identify CNS biomarkers of response. Methods: We conducted an investigator-initiated open-label phase 2 trial of Pembrolizumab in pts with LMM from any solid tumor (NCT03091478). Eligible pts had: LMM on MRI ( > 3mm lesion) or CSF cytology, ECOG PS ≤1, and were PD-naïve. Prior RT to LMM was allowed > 3 months before study start or to non-target areas. Pembrolizumab was administered IV 200mg q3W until disease progression/unacceptable toxicity. The primary endpoint was CNS response after 12 weeks, defined as radiologic (RECIST 1.1)/cytologic/clinical response to therapy. Serial CSF samples were assessed by chromosomal copy number changes using a PCR-based approach (RealSeqS) to detect tumor-derived DNA (CSF-tDNA), and 16-color flow cytometry. Results: Thirteen of a planned 18 pts were treated 04/2017-12/2019, the study was closed early for low accrual. Median age was 58 years (22-79), 53% were female. Pts had breast carcinoma (38%, n = 5), NSCLC (23%, n = 3), high-grade glioma (23%, n = 3), HNSCC (8%, n = 1) and cutaneous squamous cell carcinoma (8%, n = 1). Median no. of prior therapies was 4 (0-8), 76% of pts had prior RT to LMM. CNS response was seen in 38% of pts (5/13: 2 = complete response (NSCLC; Squamous skin); 3 = stable disease (NSCLC, Glioma, HER2+BC) by RECIST 1.1. Treatment-related adverse events were seen in 31% (4/13) of pts, 15% (2/13) G3+ (fatigue = 1, infection = 1). CSF cytology was negative at ICI start in 6 cases, but positive by CSF-tDNA in 5/6 cases. In addition, CSF-tDNA levels can correlate with disease status. CSF flow cytometry demonstrated increase in CD45R0+ activated memory T-cells, and a shift from immature to antibody-secreting B-cells in both pts with CRs in LMM. Conclusions: Pembrolizumab was well-tolerated and demonstrated anti-tumor activity in pts with LMM in ICI-responsive tumors. Correlative analyses identified CSF-tDNA can potentially be used from diagnosis to longitudinally monitor LMM; and that T and B cell populations may be enriched in the CSF of pts whose LMM regressed. These findings support inclusion of pts with LMM in ICI studies and interrogation of CSF biomarkers. Clinical trial information: NCT03091478.

Best Foot Forward: Neoadjuvant Systemic Therapy as Standard of Care in Triple-Negative and HER2-Positive Breast Cancer

Neoadjuvant systemic treatment of early-stage breast cancer has been used to improve resectability and reduce the extent of breast and axillary surgery. More recently, several other merits of neoadjuvant systemic treatment have emerged, including the ability to tailor clinically available adjuvant systemic therapy options based on pathologic response and to serve as a platform for early assessment of novel agents and response biomarkers and as an avenue for treatment optimization investigations (local and systemic therapy escalation and de-escalation trials guided by pathologic response). Attainment of a pathologic complete response (pCR) is associated with excellent long-term outcomes; conversely, the presence of residual disease is associated with a high risk of recurrence for patients with HER2-positive breast cancer and triple-negative breast cancer (TNBC). Treatment strategies in early-stage HER2-positive breast cancer include regimens incorporating trastuzumab, pertuzumab, ado-trastuzumab emtansine, and neratinib, resulting in high pCR rates and overall excellent long-term outcomes. Currently available cytotoxic regimens yield pCR for 35% to 55% of patients with TNBC, and immune checkpoint inhibition is showing early promise for this subtype. New drug and predictive biomarker evaluations in the neoadjuvant setting aim to develop optimal treatment strategies for the individual patient, with the ultimate goal of maximizing efficacy and minimizing toxicity. Research efforts involving novel agents are being undertaken to address the high risk of recurrence for patients with residual disease. Omission of breast surgery following neoadjuvant chemotherapy requires further development of imaging and biopsy techniques to accurately assess the extent of residual disease before clinical application.

Conducting a Virtual Clinical Trial in HER2-Negative Breast Cancer Using a Quantitative Systems Pharmacology Model With an Epigenetic Modulator and Immune Checkpoint Inhibitors

The survival rate of patients with breast cancer has been improved by immune checkpoint blockade therapies, and the efficacy of their combinations with epigenetic modulators has shown promising results in preclinical studies. In this prospective study, we propose an ordinary differential equation (ODE)-based quantitative systems pharmacology (QSP) model to conduct an in silico virtual clinical trial and analyze potential predictive biomarkers to improve the anti-tumor response in HER2-negative breast cancer. The model is comprised of four compartments: central, peripheral, tumor, and tumor-draining lymph node, and describes immune activation, suppression, T cell trafficking, and pharmacokinetics and pharmacodynamics (PK/PD) of the therapeutic agents. We implement theoretical mechanisms of action for checkpoint inhibitors and the epigenetic modulator based on preclinical studies to investigate their effects on anti-tumor response. According to model-based simulations, we confirm the synergistic effect of the epigenetic modulator and that pre-treatment tumor mutational burden, tumor-infiltrating effector T cell (Teff) density, and Teff to regulatory T cell (Treg) ratio are significantly higher in responders, which can be potential biomarkers to be considered in clinical trials. Overall, we present a readily reproducible modular model to conduct in silico virtual clinical trials on patient cohorts of interest, which is a step toward personalized medicine in cancer immunotherapy.

The Effects of a Remote-based Weight Loss Program on Adipocytokines, Metabolic Markers, and Telomere Length in Breast Cancer Survivors: the POWER-Remote Trial

PURPOSE

We initiated a clinical trial to determine the proportion of breast cancer survivors achieving ≥5% weight loss using a remotely delivered weight loss intervention (POWER-remote) or a self-directed approach, and to determine the effects of the intervention on biomarkers of cancer risk including metabolism, inflammation, and telomere length.

EXPERIMENTAL DESIGN

Women with stage 0-III breast cancer, who completed local therapy and chemotherapy, with a body mass index ≥25 kg/m² were randomized to a 12-month intervention (POWER-remote) versus a self-directed approach. The primary objective was to determine the number of women who achieved at least 5% weight loss at 6 months. We assessed baseline and 6-month change in a panel of adipocytokines (adiponectin, leptin, resistin, HGF, NGF, PAI1, TNFα, MCP1, IL1β, IL6, and IL8), metabolic factors (insulin, glucose, lipids, hs-CRP), and telomere length in peripheral blood mononuclear cells.

RESULTS

From 2013 to 2015, 96 women were enrolled, and 87 were evaluable for the primary analysis; 45 to POWER-remote and 42 to self-directed. At 6 months, 51% of women randomized to POWER-remote lost ≥5% of their baseline body weight, compared with 12% in the self-directed arm [OR, 7.9; 95% confidence interval (CI), 2.6-23.9; P = 0.0003]; proportion were similar at 12 months (51% vs 17%, respectively, P = 0.003). Weight loss correlated with significant decreases in leptin, and favorable modulation of inflammatory cytokines and lipid profiles. There was no significant change in telomere length at 6 months.

CONCLUSIONS

A remotely delivered weight loss intervention resulted in significant weight loss in breast cancer survivors, and favorable effects on several biomarkers.

Vulnerability of seagrass blue carbon to microbial attack following exposure to warming and oxygen

Seagrass meadows store globally-significant quantities of organic 'blue' carbon. These blue carbon stocks are potentially vulnerable to anthropogenic stressors (e.g. coastal development, climate change). Here, we tested the impact of oxygen exposure and warming (major consequences of human disturbance) on rates of microbial carbon break-down in seagrass sediments. Active microbes occurred throughout seagrass sediment profiles, but deep, ancient sediments (~5000 yrs. old) contained only 3% of the abundance of active microbes as young, surface sediments (<2 yrs. old). Metagenomic analysis revealed that microbial community structure and function changed with depth, with a shift from proteobacteria and high levels of genes involved in sulfur cycling in the near surface samples, to a higher proportion of firmicutes and euraracheota and genes involved in methanogenesis at depth. Ancient carbon consisted almost entirely (97%) of carbon considered 'thermally recalcitrant', and therefore presumably inaccessible to microbial attack. Experimental warming had little impact on carbon; however, exposure of ancient sediments to oxygen increased microbial abundance, carbon uptake and sediment carbon turnover (34-38 fold). Overall, this study provides detailed characterization of seagrass blue carbon (chemical stability, age, associated microbes) and suggests that environmental disturbances that expose coastal sediments to oxygen (e.g. dredging) have the capacity to diminish seagrass sediment carbon stocks by facilitating microbial remineralisation.

Pre- and Postoperative Neratinib for HER2-Positive Breast Cancer Brain Metastases: Translational Breast Cancer Research Consortium 022

PURPOSE

This pilot study was performed to test our ability to administer neratinib monotherapy before clinically recommended craniotomy in patients with HER2-positive metastatic breast cancer to the central nervous system, to examine neratinib's central nervous system penetration at craniotomy, and to examine postoperative neratinib maintenance.

PATIENTS AND METHODS

Patients with HER2-positive brain metastases undergoing clinically indicated cranial resection of a parenchymal tumor received neratinib 240 mg orally once a day for 7 to 21 days preoperatively, and resumed therapy postoperatively in 28-day cycles. Exploratory evaluations of time to disease progression, survival, and correlative tissue, cerebrospinal fluid (CSF), and blood-based analyses examining neratinib concentrations were planned. The study was registered at ClinicalTrials.gov under number NCT01494662.

RESULTS

We enrolled 5 patients between May 22, 2013, and October 18, 2016. As of March 1, 2019, patients had remained on the study protocol for 1 to 75+ postoperative cycles pf therapy. Two patients had grade 3 diarrhea. Evaluation of the CSF showed low concentrations of neratinib; nonetheless, 2 patients continued to receive therapy without disease progression for at least 13 cycles, with one on-study treatment lasting for nearly 6 years. Neratinib distribution in surgical tissue was variable for 1 patient, while specimens from 2 others did not produce conclusive results as a result of limited available samples.

CONCLUSION

Neratinib resulted in expected rates of diarrhea in this small cohort, with 2 of 5 patients receiving the study treatment for durable periods. Although logistically challenging, we were able to test a limited number of CSF- and parenchymal-based neratinib concentrations. Our findings from resected tumor tissue in one patient revealed heterogeneity in drug distribution and tumor histopathology.

Sharing in care: engaging care partners in the care and communication of breast cancer patients

PURPOSE

Family is often overlooked in cancer care. We developed a patient-family agenda setting intervention to engage family in cancer care communication.

METHODS

We conducted a pilot randomized controlled trial (NCT03283553) of patients on active treatment for breast cancer and their family "care partner." Intervention dyads (n = 69) completed a self-administered checklist to clarify care partner roles, establish a shared visit agenda, and facilitate MyChart patient portal access. Control dyads (n = 63) received usual care. We assessed intervention acceptability and initial effects from post-visit surveys and MyChart utilization at 6 weeks.

RESULTS

At baseline, most patients (89.4%) but few care partners (1.5%) were registered for MyChart. Most patients (79.4%) wanted their care partner to have access to their records and 39.4% of care partners reported accessing MyChart. In completing the checklist, patients and care partners endorsed active communication roles for the care partner and identified a similar visit agenda: most (> 90%) reported the checklist was easy, useful, and recommended it to others. At 6 weeks, intervention (vs control) care partners were more likely to be registered for MyChart (75.4% vs 1.6%; p < 0.001), to have logged in (43.5% vs 0%; p < 0.001) and viewed clinical notes (30.4% vs 0%; p < 0.001), but were no more likely to exchange direct messages with clinicians (1.5% vs 0%; p = 0.175). No differences in patients' MyChart use were observed, but intervention patients more often viewed clinical notes (50.7% vs 9.5%; p < 0.001).

CONCLUSIONS

A patient-family agenda setting intervention was acceptable and affected online practices of cancer patients and care partners.

TBCRC 022: A Phase II Trial of Neratinib and Capecitabine for Patients With Human Epidermal Growth Factor Receptor 2-Positive Breast Cancer and Brain Metastases

PURPOSE

Evidence-based treatments for metastatic, human epidermal growth factor receptor 2 (HER2)-positive breast cancer to the CNS are limited. We previously reported modest activity of neratinib monotherapy for HER2-positive breast cancer brain metastases. Here we report the results from additional study cohorts.

PATIENTS AND METHODS

Patients with measurable, progressive, HER2-positive brain metastases (92% after receiving CNS surgery and/or radiotherapy) received neratinib 240 mg orally once per day plus capecitabine 750 mg/m² twice per day for 14 days, then 7 days off. Lapatinib-naïve (cohort 3A) and lapatinib-treated (cohort 3B) patients were enrolled. If nine or more of 35 (cohort 3A) or three or more of 25 (cohort 3B) had CNS objective response rates (ORR), the drug combination would be deemed promising. The primary end point was composite CNS ORR in each cohort separately, requiring a reduction of 50% or more in the sum of target CNS lesion volumes without progression of nontarget lesions, new lesions, escalating steroids, progressive neurologic signs or symptoms, or non-CNS progression.

RESULTS

Forty-nine patients enrolled in cohorts 3A (n = 37) and 3B (n = 12; cohort closed for slow accrual). In cohort 3A, the composite CNS ORR = 49% (95% CI, 32% to 66%), and the CNS ORR in cohort 3B = 33% (95% CI, 10% to 65%). Median progression-free survival was 5.5 and 3.1 months in cohorts 3A and 3B, respectively; median survival was 13.3 and 15.1 months. Diarrhea was the most common grade 3 toxicity (29% in cohorts 3A and 3B).

Neratinib plus capecitabine is active against refractory, HER2-positive breast cancer brain metastases, adding additional evidence that the efficacy of HER2-directed therapy in the brain is enhanced by chemotherapy. For optimal tolerance, efforts to minimize diarrhea are warranted.

Abstract P4-16-09: Effect of simvastatin on cardiac strain in breast cancer patients receiving anthracycline therapy

Background: Cardiac toxicity (CT) is a rare late effect of anthracycline therapy for breast cancer (BC). Statins may attenuate the CT of anthracyclines. Myocardial strain can detect subclinical CT before ejection fraction (EF) declines. Global longitudinal strain (GLS) ≥-19% and relative change (RelΔ) in GLS≥11% predict future decline in EF. We conducted a pilot study to evaluate the effect of simvastatin on GLS in BC patients receiving anthracyclines. Methods: We enrolled women with stage I-III BC planning doxorubicin/cyclophosphamide (AC) x 4. Women with heart disease or taking a statin were excluded. Participants were randomized 1:1 to simvastatin 40 mg daily x 24 weeks (wk) + AC or to AC alone. We performed echo with strain 5 times: baseline (BL), pre-AC#2, 1-3 wk after AC#4, 24 wk after AC #1 and 52 wk after AC#1. The primary endpoint was the mean absolute change (|Δ|) in GLS from BL to 1-3 wk after AC#4. Secondary endpoints included RelΔ in GLS, feasibility and safety. We used two-sample t-tests to compare mean changes in GLS and Fisher's exact test to compare dichotomized GLS values. The study closed early due to loss of staff. Results: Of 31 patients, 15 (48%) received simvastatin+AC. Mean age was 46 years; 71% pre-menopausal, 61% white and 32% black. There were no significant differences in BL cardiovascular risk factors between the arms. After AC, 3 HER2+ patients received trastuzumab. There were no grade 3-4 AEs with simvastatin. Common grade 1-2 AEs included myalgia (20%), elevated AST (27%) and elevated ALT (53%). One patient in the AC arm died from heart failure with low EF 2 months after having a normal echo 1-3 wk after AC#4. The rate of missing echos was 14%. Of 133 completed echos, 124 (93%) were evaluable for GLS. Mean GLS was &lt;-19% at all times in the simvastatin+AC arm. Mean GLS was &lt;-19% at BL and pre-AC#2 in the AC arm, but ≥-19% at post-AC times in the AC arm. Mean EF was &gt;60% at all times in both arms. Among 27 patients evaluable for the primary endpoint, there was no significant difference in mean |Δ| in GLS from BL to 1-3 wk after AC#4 between the arms (Simvastatin+AC: 0.42%; AC: 1.11%, p=0.57). In addition, there were no differences in the mean|Δ| in GLS from BL to any other time between the arms (all p&gt;0.1). The proportion of patients with GLS&lt;-19% was higher in the simvastatin+AC arm than in the AC arm pre-AC#2 (73% vs 44%), 1-3 wk after AC#4 (67% vs 38%), 24 wk after AC #1 (53% vs 25%) and 52 wk after AC#1 (53% vs 25%) (all p&gt;0.05). The proportion of patients with RelΔ in GLS≥11% from BL was lower in the simvastatin+AC arm than in the AC arm pre-AC#2 (13% vs 19%), 1-3 wk after AC#4 (20% vs 44%) and 24 wk after AC#1(27% vs 31%) (all p&gt;0.05). Conclusion: Simvastatin did not result in a statistically significant difference in the mean |Δ| in GLS from BL to 1-3 wk after AC#4. However, the study was underpowered due to small sample size and there was a suggestion of reduced CT with simvastatin. Co-administration of simvastatin and AC was safe and serial echocardiographic strain monitoring was feasible. Further studies are needed to evaluate the cardioprotective effect of statins on strain in BC patients receiving anthracyclines.

Citation Format: Smith KL, Griffin JM, Tsai H-L, Leathers M, Hays A, Lu D-Y, Zhang Z, Rosner GL, Russell SD, Connolly RM, Jelovac D, Visvanathan K, Wolff AC, Stearns V, Abraham T. Effect of simvastatin on cardiac strain in breast cancer patients receiving anthracycline therapy [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-16-09.