Real world study of sacituzumab govitecan in metastatic triple-negative breast cancer in the United Kingdom

BACKGROUND

Treatment options for pre-treated patients with metastatic triple-negative breast cancer (mTNBC) remain limited. This is the first study to assess the real-world safety and efficacy of sacituzumab govitecan (SG) in the UK.

METHODS

Data was retrospectively collected from 16 tertiary UK cancer centres. Pts had a diagnosis of mTNBC, received at least two prior lines of treatment (with at least one being in the metastatic setting) and received at least one dose of SG.

RESULTS

132 pts were included. Median age was 56 years (28-91). All patients were ECOG performance status (PS) 0-3 (PS0; 39, PS1; 76, PS2; 16, PS3;1). 75% (99/132) of pts had visceral metastases including 18% (24/132) of pts with CNS disease. Median PFS (mPFS) was 5.2 months (95% CI 4.5-6.6) with a median OS (mOS) of 8.7 months (95% CI 6.8-NA). The most common adverse events (AEs) were fatigue (all grade; 82%, G3/4; 14%), neutropenia (all grade; 55%, G3/4; 29%), diarrhoea (all grade; 58%, G3/4, 15%), and nausea (all grade; 38%, G3/4; 3%). SG dose reduction was required in 54% of pts.

CONCLUSION

This study supports significant anti-tumour activity in heavily pre-treated pts with mTNBC. Toxicity data aligns with clinical trial experience.

Effect of exercise before and/or during taxane-containing chemotherapy treatment on chemotherapy-induced peripheral neuropathy symptoms in women with breast cancer: systematic review and meta-analysis

PURPOSE

To systematically review and meta-analyse the efficacy of exercise interventions delivered before and/or during taxane-containing chemotherapy regimens on chemotherapy-induced peripheral neuropathy (CIPN), fatigue, and health-related quality of life (HR-QoL), in women with breast cancer.

METHODS

Seven electronic databases were systematically searched for randomised controlled trials (RCTs) reporting on the effects of exercise interventions in women with breast cancer receiving taxane-containing chemotherapeutic treatment. Meta-analyses evaluated the effects of exercise on CIPN symptoms, fatigue, and HR-QoL.

RESULTS

Ten trials involving exercise interventions ranging between 2 and 12 months were included. The combined results of four RCTs consisting of 171 participants showed a reduction in CIPN symptoms following exercise compared with usual care (standardised mean difference - 0.71, 95% CI - 1.24 to - 0.17, p = 0.012; moderate-quality evidence, I2 = 76.9%). Pooled results from six RCTs with 609 participants showed that exercise interventions before and/or during taxane-containing chemotherapy regimens improved HR-QoL (SMD 0.42, 95% CI 0.07 to 0.76, p = 0.03; moderate-quality evidence, I2 = 49.6%). There was no evidence of an effect of exercise on fatigue (- 0.39, 95% CI - 0.95 to 0.18, p = 0.15; very low-quality evidence, I2 = 90.1%).

CONCLUSIONS

This systematic review found reduced levels of CIPN symptoms and an improvement in HR-QoL in women with breast cancer who exercised before and/or during taxane-based chemotherapy versus usual care controls.

IMPLICATIONS FOR CANCER SURVIVORS

This evidence supports the role of exercise as an adjunctive treatment for attenuating the adverse effects of taxane-containing chemotherapy on CIPN symptoms and HR-QoL.

Preventing cardiotoxicity in patients with breast cancer and lymphoma: protocol for a multicentre randomised controlled trial (PROACT)

INTRODUCTION

Anthracyclines are included in chemotherapy regimens to treat several different types of cancer and are extremely effective. However, it is recognised that a significant side effect is cardiotoxicity; anthracyclines can cause irreversible damage to cardiac cells and ultimately impaired cardiac function and heart failure, which may only be evident years after exposure. The PROACT trial will establish the effectiveness of the ACE inhibitor enalapril maleate (enalapril) in preventing cardiotoxicity in patients with breast cancer and non-Hodgkin's lymphoma (NHL) receiving anthracycline-based chemotherapy.

METHODS AND ANALYSIS

PROACT is a prospective, randomised, open-label, blinded end-point, superiority trial which will recruit adult patients being treated for breast cancer and NHL at NHS hospitals throughout England. The trial aims to recruit 106 participants, who will be randomised to standard care (high-dose anthracycline-based chemotherapy) plus enalapril (intervention) or standard care alone (control). Patients randomised to the intervention arm will receive enalapril (starting at 2.5 mg two times per day and titrating up to a maximum dose of 10 mg two times per day), commencing treatment at least 2 days prior to starting chemotherapy and finishing 3 weeks after their last anthracycline dose. The primary outcome is the presence or absence of cardiac troponin T release at any time during anthracycline treatment, and 1 month after the last dose of anthracycline. Secondary outcomes will focus on cardiac function measured using echocardiogram assessment, adherence to enalapril and side effects.

ETHICS AND DISSEMINATION

A favourable opinion was given following research ethics committee review by West Midlands-Edgbaston REC, Ref: 17/WM/0248. Trial findings will be disseminated through engagement with patients, the oncology and cardiology communities, NHS management and commissioning groups and through peer-reviewed publication.

TRIAL REGISTRATION NUMBER

NCT03265574.

Results of the phase IIa RADICAL trial of the FGFR inhibitor AZD4547 in endocrine resistant breast cancer

We conducted a phase IIa, multi-centre, open label, single arm study (RADICAL; NCT01791985) of AZD4547 (a potent and selective inhibitor of Fibroblast Growth Factor Receptor (FGFR)-1, 2 and 3 receptor tyrosine kinases) administered with anastrozole or letrozole in estrogen receptor positive metastatic breast cancer patients who had become resistant to aromatase inhibitors. After a safety run-in study to assess safety and tolerability, we recruited 52 patients. The primary endpoint was change in tumour size at 12 weeks, and secondary endpoints were to assess response at 6 weeks, 20 weeks and every 8 weeks thereafter and tolerability of the combined treatment. Two partial responses (PR) and 19 stable disease (SD) patients were observed at the 12-week time point. At 28 weeks, according to centrally reviewed Response Evaluation Criteria in Solid Tumours (RECIST) criteria, five PR and 8 SD patients were observed in 50 assessable cases. Overall, objective response rate (5 PR) was of 10%, meeting the pre-specified endpoint. Fourteen patients discontinued due to adverse events. Eleven patients had retinal pigment epithelial detachments which was asymptomatic and reversible in all but one patient. Exploratory ribonucleic acid sequencing (RNA-Seq) analysis was done on patients' samples: 6 differentially-expressed-genes could distinguish those who benefited from the addition of AZD4547.

Abstract 1406: Are circulating microRNAs (miRNAs) ready for inclusion as biomarkers in breast cancer clinical trials

Background: Circulating miRNAs have potential as surrogate measures of tumor burden to monitor treatment response in clinical trials due to their association with cancer and high stability in blood. Greystoke et al (PMID: 26654130) showed that 10 miRNAs (miRs-200a, 200b, 200c, 141, 429, 95, 195, 210, 335, 375) were elevated in plasma of patients with a range of solid tumors compared to in plasma of healthy volunteers (HVs). The miRNA levels decreased after treatment, especially in patients with larger clinical responses. In the present study, the same 10 miRNAs, and 3 breast cancer (BC) related miRNAs identified in a literature search (miRs-18b, 21, 148b), were analysed to determine if their measurement i) is more sensitive in plasma or serum, ii) distinguishes BC patients from HVs, and iii) changes after surgery or systemic therapy.

Methods: The 13-miRNA panel (13-plex) was analysed by qPCR in plasma and serum from 12 BC patients and 8 HVs, and in plasma from 19 BC patients pre- and 4 hours post-surgery with a multiplex of TaqManTM MiRNA Assays. Expression of the 13-plex was measured with custom TaqManTM Low Density Array (TLDA) cards after pre-amplification, in serum collected at cycle 1, day 1 (C1D1) and day 8 (C1D8) from 44 BC patients starting adjuvant chemotherapy on the B-AHEAD 2 study (ISRCTN04156504). Endogenous miR-16 and exogenous ath-miR-159a provided standards to assess miRNA extraction efficiency. Results are reported as the geometric means of the 40-Ct values for the 13 miRNAs (geomean13).

Results: Expression of the 13-plex was significantly higher in plasma compared to in matched serum. TLDA analysis of 381 miRNAs confirmed that the plasma to serum superiority was a general effect not restricted to the 13-plex. The superiority of plasma was reduced however by pre-amplification; in the 381-miRNA TLDA analysis, detection in serum improved compared to in the multiplex qPCR assay.

The 13-plex was elevated in plasma of BC patients compared to HVs (p = 0.015). There was a trend towards a reduction after surgery, but the difference did not reach statistical significance. However, miR-195, a BC specific marker, was significantly lower after surgery (p = 0.0001). In the B-AHEAD 2 study cohort, the 13-plex was decreased at C1D8 compared to C1D1 (p = 0.0002). The three patients who relapsed within 5 years of diagnosis had geomean13 values at C1D1 of 10.3, 10.6 and 11.8 compared to the median of 10.3 for all patients. Given the low event rate, either a larger patient cohort or a cohort with a higher event rate is required to assess association with clinical outcome.

Conclusions: This study shows that plasma is better than serum for miRNA evaluation but that measures in serum are useful if cDNA is pre-amplified after reverse transcription. The 13-plex is elevated in BC, has a trend towards a fall after surgery and is reduced after chemotherapy. The 13-plex has potential as a biomarker of tumor burden in BC trials.

Citation Format: Edward B. Amankwatia, Alexandra Bennett, David Ou, David Jamieson, Nicola Cresti, Henry Cain, Rosie McNeillis, Jonathan Womack, Sacha Howell, Michelle Harvie, Felicity May, Alastair Greystoke. Are circulating microRNAs (miRNAs) ready for inclusion as biomarkers in breast cancer clinical trials [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 1406.

First-in-human study of the PARP/tankyrase inhibitor E7449 in patients with advanced solid tumours and evaluation of a novel drug-response predictor

Background

This phase 1 study examined the safety, maximum-tolerated dose (MTD) and antitumour activity of E7449, a novel PARP 1/2 and tankyrase 1/2 inhibitor.

Methods

E7449 was orally administered once daily in 28-day cycles to patients with advanced solid tumours (50–800-mg doses). Archival tumour samples from consenting patients were evaluated for the expression of 414 genes in a biomarker panel (2X-121 drug-response predictor [DRP]) found to be predictive of the response to E7449 in cell lines.

Results

Forty-one patients were enrolled (13 pancreatic, 5 ovarian, 4 each with breast, lung or colorectal cancer and 11 with other tumour types). The most common grade ≥3 treatment-related adverse event was fatigue (n = 7, 17.1%). Five patients experienced a dose-limiting toxicity (fatigue, n = 4, 800 mg; anaphylaxis, n = 1, 600 mg) for an MTD of 600 mg. E7449 exhibited antitumour activity in solid tumours, including 2 partial responses (PRs), and stable disease (SD) in 13 patients, which was durable (>23 weeks) for 8 patients. In 13 patients, the 2X-121 DRP identified those achieving PR and durable SD. E7449 showed good tolerability, promising antitumour activity and significant concentration-dependent PARP inhibition following 50–800-mg oral dosing.

Conclusion

The results support further clinical investigation of E7449 and its associated biomarker 2X-121 DRP.

Clinical trial registration

www.ClinicalTrials.gov code: NCT01618136.

A phase I/II study of epertinib plus trastuzumab with or without chemotherapy in patients with HER2-positive metastatic breast cancer

BACKGROUND

Epertinib (S-222611) is a potent reversible inhibitor of HER2, EGFR and HER4. This trial evaluated the safety, tolerability, pharmacokinetics and antitumour activity of daily oral epertinib combined with trastuzumab (arm A), with trastuzumab plus vinorelbine (arm B) or with trastuzumab plus capecitabine (arm C), in patients with HER2-positive metastatic breast cancer (MBC).

METHODS

Eligible patients, with or without brain metastases, had received prior HER2-directed therapy. A dose-escalation phase determined the tolerability of each combination and established a dose for further study. Further, patients were recruited to expansion cohorts in each of the 3 arms to further explore efficacy and safety.

RESULTS

The recommended doses of epertinib were 600 mg, 200 mg and 400 mg in arms A, B and C, respectively. The most frequent grade 3/4 adverse event (AE) was diarrhoea in all arms, which was manageable with medical intervention and dose modification. The objective response rate (complete response [CR] plus partial response [PR]) in heavily pre-treated HER2-positive MBC patients at the recommended doses of epertinib combined with trastuzumab was 67% (N = 9), with trastuzumab plus vinorelbine was 0% (N = 5) and with trastuzumab plus capecitabine was 56% (N = 9). Notably, 4 of 6 patients previously treated with T-DM1 responded in the arm A expansion cohort (epertinib plus trastuzumab). In the arm C expansion cohort (epertinib plus trastuzumab plus capecitabine), 4 of 7 patients responded despite previous exposure to capecitabine. Measurable regression of brain metastases was observed in patients with CNS target lesions treated in both arms A and C.

CONCLUSION

We observed safety, tolerability and encouraging antitumour activity of epertinib combined with trastuzumab, or with trastuzumab plus capecitabine. This supports further evaluation of these combinations in patients with pre-treated HER2-positive MBC, with or without brain metastases.

TRIAL REGISTRATION

EudraCT Number: 2013-003894-87; registered 09-September-2013.

A phase 1b/2, open-label, dose-escalation, and dose-confirmation study of eribulin mesilate in combination with capecitabine

BACKGROUND

Capecitabine and eribulin are widely used as single agents in metastatic breast cancer (MBC) and have nonoverlapping toxicities.

METHODS

In phase 1b (dose escalation), patients with advanced, treatment-refractory, solid tumours received eribulin mesilate intravenously in 21-day cycles according to schedule 1 (day 1) or schedule 2 (days 1, 8) with twice-daily oral capecitabine (1000 mg/m2 days 1-14). In phase 2 (dose confirmation), women with advanced/MBC and ≤3 prior chemotherapies received eribulin mesilate at the maximum tolerated dose (MTD) per the preferred schedule plus capecitabine. Primary objectives were MTD and dose-limiting toxicities (DLTs; phase 1b) and objective response rate (ORR; phase 2). Secondary objectives included progression-free survival (PFS), safety, and pharmacokinetics.

RESULTS

DLTs occurred in 4/19 patients (schedule 1) and 2/15 patients (schedule 2). Eribulin pharmacokinetics were dose proportional, irrespective of schedule or capecitabine coadministration. The MTD of eribulin was 1.6 mg/m2 day 1 for schedule 1 and 1.4 mg/m2 days 1 and 8 for schedule 2. ORR in phase 2 (eribulin 1.4 mg/m2 days 1, 8 plus capecitabine) was 43% and median PFS 7.2 months. The most common treatment-related adverse events were neutropenia, leukopenia, alopecia, nausea, and lethargy.

CONCLUSIONS

The combination of capecitabine and eribulin showed promising efficacy with manageable tolerability in patients with MBC.

RADICAL trial: A phase Ib/IIa study to assess the safety and efficacy of AZD4547 in combination with either anastrozole or letrozole in ER positive breast cancer patients progressing on these aromatase inhibitors (AIs)

1059

Background: Patients with metastatic ER positive breast cancer invariably experience disease progression whilst taking AIs. Fibroblast growth factor receptor inhibitors (FGFRI) such as AZD4547 can reverse endocrine resistance in breast cancer cells. Consequently, we designed the RADICAL trial to test the safety and efficacy of AZD4547 combined with letrozole (L) or anastrozole (A). Methods: Patients with prior disease progression on either AI were initially recruited to a Phase Ib study which showed that L 2.5mg or A 1mg daily continuously could be safely combined with AZD4547 80mg twice daily on a 1wk on/1 wk off schedule. Pharmacokinetic data showed no significant interactions. Subsequently, 52 patients progressing on these AIs were recruited, either continuing, or, if other therapies had subsequently been given, restarting their prior AI together with AZD4547. Primary endpoint was change in tumour size (RECIST v 1.1) at 12 weeks compared to baseline. Results: Enrolled patients had previously received a median of 4 (range: 1-11) systemic therapies, including endocrine treatments with a median of 2 (range: 1-6). The mean tumour size change at 12 and 28 weeks was 7% (95%CI: -4%, 17%) and 8% (95%CI: -4%, 20%), respectively. Clinical benefit assessed by partial response (PR) or stable disease (SD) occurred in 36.5% (1 PR and 18 SD) and 25% (2 PR and 11 SD) of patients at 12 and 28 weeks, respectively. The median progression free survival was 3.1 months (95%CI: 2.4-5.4). Most adverse events (AEs) were G1/2 (95.3%). 11 (21%) patients developed asymptomatic AZD4547-induced retinal pigment epithelial detachment, all resolved and 1 and 6 were able to continue on study medication at full and half dose, respectively. Among 34 G3/4 AEs, only 6 were probably/possibly related to AZD4547. Out of 13 unrelated serious AEs, 2 were fatal. Conclusions: Combined AZD4547 with L or A appears to be safe and shows anti-tumour activity in advanced ER+ patients resistant to these AIs. Development of a biomarker to select patients for this therapy will facilitate future studies. Clinical trial information: NCT01791985.

Abstract P4-21-08: A phase I/II of S-222611, a reversible EGFR and HER2 inhibitor, combined with trastuzumab +/- chemotherapy in patients with HER2-positive metastatic breast cancer

Background: S-222611, an oral, reversible EGFR and HER2 inhibitor, has been shown to be well-tolerated as monotherapy at a dose of 800mg daily with good anti-tumor activity in patients previously treated with other anti-HER2-based regimens. This study evaluated the tolerability and safety of daily oral administration of S-222611 (S) in combination with trastuzumab (T), trastuzumab + vinorelbine (T+V) and trastzumab + capecitabine (T+C) in HER2-positive (HER2+) metastatic breast cancer (MBC) with or without brain metastases.

Methods: This study was performed as a 3+3 dose escalation followed by expansion to examine the tolerability and safety of S in combination with T, T+V and T+C in Arms A, B and C, respectively. S was administered orally once daily, starting at a dose of 400mg in Arm A, and 200mg in Arms B and C. The dosing of T was 8mg/kg loading followed by 6mg/kg or fixed dose of 600mg subcutaneously every 21 days as recommended. V was administered at 60mg/m2 orally on Day 1 and 8 of a 21-day cycle, and C 1000mg/m2 orally daily for 14 days followed by a 7-day rest period. All patients had HER2+ MBC and were required to have progressed following at least one prior line of anti-HER2 therapy. Prior treatments with V and C were permitted. Anti-diarrhea prophylaxis with loperamide was not required.

Results: A total of 45 patients were enrolled. All patients had received prior anti-tumor regimens including T (n=45), T-DM1 (n=26), pertuzumab (n=9) and lapatinib (n=12). The clinically recommended doses of S at which most adverse events were manageable,were determined as:600mg in Arm A, 200mg in Arm B and 400mg in Arm C. Dose limiting toxicities included Grade 3 diarrhea for Arm A; and Grade 4 neutropenia, Grade 3 Hypokalemia and Hypophosphatemia for Arm B. As of 13 May 2016, treatment is ongoing in 2 patients. No other Grade 4 AEs related to S-222611 have been observed. Grade 3 bilirubin elevation was observed in 5/45 patients, probably due to transporter (UGT1A1) inhibition, while no G3/4 liver dysfunction was reported. RECIST partial responses (PR) were observed in 6 of 9 patients in Arm A and 5 of 9 patients in Arm C, at respective clinically recommended doses. Nine of 45 patients had brain metastases; 4 of these patients showed RECIST PR including an intracranial tumor response in one patient (400mg in Arm C) who had prior treatments with paclitaxel, T+C, T-DM1 and V after diagnosis of BM.

Conclusions: The clinically recommended doses of S-222611 combined with T, T +V and T+C were determined for further clinical studies. Clinical benefit (PR and SD >6 month) was seen with each combination even in heavily pre-treated HER2+ MBC patients.

Summary of the safety and efficacy of S-222611 (S) combination. Dose (mg)nDLT (1st cycle)G3 Diarrhea during study (N of patients)RECIST tumor response, PR n/ SD ≥6M nORR n (%)CBR n (%)Arm A: S + T4005010/10/5 (0%)1/5 (20%)Arm A: S + T6009036/06/9 (67%)6/9 (67%)Arm A: S + T8007141/11/7 (14%)2/7 (29%)Arm B: S + T + V2005020/40/5 (0%)4/5 (80%)Arm B: S + T + V4002211/01/2 (50%)1/2 (50%)Arm C: S + T + C2004010/10/4 (0%)1/4 (25%)Arm C: S + T + C4009025/05/9 (56%)5/9 (56%)Arm C: S + T + C6004022/12/4 (50%)3/4 (75%)

Citation Format: Rafii S, Macpherson I, Baird R, Saggese M, Spiliopoulou P, Kumar S, Italiano A, Bonneterre J, Campone M, Cresti N, Posner J, Takeda Y, Arimura A, Spicer J. A phase I/II of S-222611, a reversible EGFR and HER2 inhibitor, combined with trastuzumab +/- chemotherapy in patients with HER2-positive metastatic breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P4-21-08.

Pharmacogenetic association of MBL2 and CD95 polymorphisms with grade 3 infection following adjuvant therapy for breast cancer with doxorubicin and cyclophosphamide

Life-threatening infection as an adverse reaction to cytotoxic therapy of cancer remains a major problem, potentially limiting efficacy. Administration of colony-stimulation factors benefits only a minority of patients, and improved stratification guidelines are needed to identify those patients likely to benefit. We investigated single nucleotide polymorphisms (SNPs) in two genes related to immune function to identify associations with severe infection following treatment of breast cancer with doxorubicin and cyclophosphamide. CD95 mediates the extrinsic apoptosis pathway in haematopoietic cells and a CD95 promoter SNP (rs2234767) has been shown to result in reduced expression of the receptor. MBL2 activates the classical complement pathway in the presence of pathogens and independently of antibodies. Numerous SNPs have been described including a promoter SNP (rs7096206) which results in decreased expression of the protein. Homozygotes for the CD95 minor allele were more likely to experience a grade 3 infection than heterozygote and homozygote wild-type patients (29%, 3% and 5%, respectively p=0.048). CD95 minor allele homozygotes also had higher basal white blood cell and neutrophil counts compared with wild-type allele carriers, which was sustained throughout therapy. There was an allele-dose association between the MBL2 SNP and grade 3 infection, with 2, 8 and 17% of wild-type homozygotes, heterozygotes and minor allele homozygotes, respectively, experiencing grade 3 infection (p=0.02). These associations demonstrate the utility of a pharmacogenetic approach to identify individuals more likely to acquire a life-threatening infection during chemotherapy. The apparent association with a CD95 SNP and a mild neutrophilia merits further investigation.

A phase I pharmacokinetic and pharmacodynamic study of the oral mitogen-activated protein kinase kinase (MEK) inhibitor, WX-554, in patients with advanced solid tumours

PURPOSE

We performed a multi-centre phase I study to assess the safety, pharmacokinetics (PK) and pharmacodynamics (PD) of the orally available small molecule mitogen-activated protein kinase kinase (MEK) 1/2 inhibitor, WX-554, and to determine the optimal biological dose for subsequent trials.

EXPERIMENTAL DESIGN

Patients with treatment-refractory, advanced solid tumours, with adequate performance status and organ function were recruited to a dose-escalation study in a standard 3 + 3 design. The starting dose was 25 mg orally once weekly with toxicity, PK and PD guided dose-escalation with potential to explore alternative schedules.

RESULTS

Forty-one patients with advanced solid tumours refractory to standard therapies and with adequate organ function were recruited in eight cohorts up to doses of 150 mg once weekly and 75 mg twice weekly. No dose-limiting toxicities were observed during the study, and a maximum tolerated dose (MTD) was not established. The highest dose cohorts demonstrated sustained inhibition of extracellular signal-regulated kinase (ERK) phosphorylation in peripheral blood mononuclear cells following ex-vivo phorbol 12-myristate 13-acetate stimulation. There was a decrease of 70 ± 26% in mean phosphorylated (p)ERK in C1 day 8 tumour biopsies when compared with pre-treatment tumour levels in the 75 mg twice a week cohort. Prolonged stable disease (>6 months) was seen in two patients, one with cervical cancer and one with ampullary carcinoma.

CONCLUSIONS

WX-554 was well tolerated, and an optimal biological dose was established for further investigation in either a once or twice weekly regimens. The recommended phase 2 dose is 75 mg twice weekly.

Abstract P4-14-26: Phase I expansion of S-222611, a reversible inhibitor of EGFR and HER2, in advanced solid tumors, including HER2-positive breast cancer patients with brain metastases

BACKGROUND

S-222611 is an oral, reversible ErbB tyrosine kinase inhibitor of EGFR and HER2 with potent pre-clinical activity. MTD was not reached during the dose-escalation phase, (maximum dose 1600 mg QD). PK and efficacy data supported a daily dose of 800 mg. An expansion cohort of patients has been treated to further explore safety and efficacy.

METHODS

Subjects with advanced solid tumors expressing EGFR and/or overexpressing HER2 were enrolled. S-222611 800 mg daily was administered until disease progression or unacceptable toxicity.

RESULTS

76 patients were included in this phase 1 expansion cohort with a variety of tumor types. Dose reduction was required because of adverse events in 15 patients; the most frequent of which being diarrhea and elevated bilirubin. Two patients discontinued treatment due to drug- related adverse events. Of the 25 patients with HER2-positive metastatic breast cancer (MBC), 4 partial responses were observed, and prolonged stable disease (≥ 6 months) was observed in 3 additional patients. These 25 patients had received prior HER2-directed therapy as shown in Table 1.

Table 1. Prior therapies received by patients with HER2-positive MBCPrior therapyn (%)Trastuzumab22 (88)T-DM13 (12)Lapatinib16 (64)Chemotherapy23 (92)

Six of these patients had brain metastases, in whom 1 intracranial response and 2 prolonged stable disease (≥ 6 months) were observed (Table 2).

Table 2. HER2-positive MBC patients with brain metastases - best overall response to S-222611Pts #HER2 IHCBrain metastasesBest overall response (RECIST 1.1)Patient 13+Target lesionPRPatient 23+Target lesionSD (≥12 M)Patient 33+Target lesionSD (6.0 M)Patient 43+Non-target lesionSD (4.7 M)Patient 53+Non-target lesionSD (3.3 M)Patient 63+Non-target lesionNE

The patient showing intracranial response was previously treated with lapatinib and capecitabine after diagnosis of BM.

CONCLUSIONS

S-222611 was well tolerated at a dose of 800 mg once daily. Anti-tumour activity, including shrinkage of brain metastases, was evident in a heavily pre-treated population of patients with HER2-positive breast cancer.

Citation Format: Baird RD, Arkenau H-T, Deva S, Cresti N, Garcia-Corbacho J, Hogarth L, Frenkel E, Kawaguchi K, Arimura A, Donaldson K, Posner J, Sarker D, Jodrell D, Plummer R, Spicer J, Italiano A. Phase I expansion of S-222611, a reversible inhibitor of EGFR and HER2, in advanced solid tumors, including HER2-positive breast cancer patients with brain metastases. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P4-14-26.

Calpain-1 is associated with adverse relapse free survival in breast cancer: a confirmatory study

AIMS

Calpain-1 is a ubiquitously expressed calcium-activated intracellular cysteine protease. Altered expression of calpain system proteins has been implicated in cancer progression and response to chemotherapy.

METHODS AND RESULTS

The aim of the current study was to confirm previous data that suggested that calpain-1 expression is associated with relapse-free survival in trastuzumab-treated breast cancer patients (n = 93). An expanded patient cohort from Nottingham (n = 194; including 72 of the previous cohort) and an independent patient cohort from Newcastle (n = 87) were used. All patients received trastuzumab following adjuvant therapy according to local guidelines with expression of calpain-1 investigated using standard immunohistochemistry. Results show that calpain-1 expression is associated with relapse-free survival in both the Nottingham (P = 0.01) and Newcastle (P = 0.019) cohorts, with high expression associated with adverse relapse-free survival. Expression was also associated with poor relapse-free survival when patient cohorts were combined (n = 281, P = 0.01). Calpain-1 remained, from multivariate analysis, an independent marker for relapse-free survival in the Newcastle cohort [hazard ratio (HR) = 5.169; 95% confidence interval (CI) 1.468-18.200; P = 0.011].

CONCLUSIONS

Calpain-1 expression is associated with poor relapse-free survival in breast cancer patients treated with trastuzumab. Further work is warranted to standardize and develop methodology with a view to potentially introducing assessment of this important biomarker into clinical practice.

Phase 1 dose-escalation study of S-222611, an oral reversible dual tyrosine kinase inhibitor of EGFR and HER2, in patients with solid tumours

BACKGROUND

S-222611 is a reversible inhibitor of EGFR, HER2 and HER4 with preclinical activity in models expressing these proteins. We have performed a Phase 1 study to determine safety, maximum tolerated dose (MTD), pharmacokinetic profile (PK) and efficacy in patients with solid tumours expressing EGFR or HER2.

PATIENTS AND METHODS

Subjects had advanced tumours not suitable for standard treatment, expressing EGFR or HER2, and/or with amplified HER2. Daily oral doses of S-222611 were escalated from 100mg to 1600 mg. Full plasma concentration profiles for drug and metabolites were obtained.

RESULTS

33 patients received S-222611. It was well tolerated, and the most common toxicities, almost all mild (grade 1 or 2), were diarrhoea, fatigue, rash and nausea. Only two dose-limiting toxicities occurred (diarrhoea and rash), which resolved on interruption. MTD was not reached. Plasma exposure increased with dose up to 800 mg, exceeding levels eliciting pre-clinical responses. The plasma terminal half-life was more than 24h, supporting once daily dosing. Responses were seen over a wide range of doses in oesophageal, breast and renal tumours, including a complete clinical response in a patient with HER2-positive breast carcinoma previously treated with lapatinib and trastuzumab. Four patients have remained on treatment for more than 12 months. Downregulation of pHER3 was seen in paired tumour biopsies from a responding patient.

CONCLUSIONS

Continuous daily oral S-222611 is well tolerated, modulates oncogenic signalling, and has significant antitumour activity. The recommended Phase 2 dose, based on PK and efficacy, is 800 mg/day.

Abstract P4-12-24: Phase I trial of S-222611, a dual tyrosine kinase inhibitor of EGFR and HER2, with preliminary evidence of efficacy in patients (pts) with heavily-pretreated HER2-positive metastatic breast cancer

Background and rationale: S-222611 is a novel, oral, reversible inhibitor of EGFR, HER2 and HER4 with an improved preclinical profile compared with first-generation pan-HER inhibitors.

Research objectives: We conducted a phase I study to determine safety, maximum tolerated dose (MTD), pharmacokinetics (PK), pharmacodynamics (PD) and preliminary efficacy in pts with solid tumors expressing EGFR or HER2.

Patients and methods: Pts with advanced solid tumors and biopsies confirming EGFR and/or HER2 expression were treated with continuous daily oral doses of S-222611. The dose of S-222611 was escalated in cohorts of at least 3 pts from 100mg to 1600mg. PK profiles were obtained in all pts, and PD assays for pEGFR, pHER2 and pHER3 were performed on paired tumor biopsies in selected pts.

Results: A total of 50 pts have been treated to-date; age 25-80y; 20 female; 13 with HER2-positive metastatic breast cancer (HER2+ MBC). S-222611 was generally well tolerated with two dose-limiting toxicities in the dose-escalation phase: rash at 1200mg; diarrhea at 1600mg. MTD was not defined. Diarrhea was the most frequent toxicity, but was rarely worse than grade 1/2. Nausea, rash, anorexia and fatigue were also seen. Bilirubin rises with normal transaminases were observed. Plasma concentrations of S-222611 increased with dose up to 800mg, which was the dose selected for the expansion phase. Steady state values of Cmax and AUC0-24 at this dose were in the effective range of concentrations in mouse models. Average t½ of 33h was consistent with once daily dosing. Tumor responses were seen over the full dose range tested (100-1600mg), with four pts on treatment for >12 months. Out of 13 HER2+ MBC pts, one clinical complete response (CR) was observed for >12 months, and four partial responses (PRs) were also seen (2 confirmed, 2 unconfirmed), yielding an overall response rate of 38% in this small group (Table 1). All 5 responding patients had previously progressed on trastuzumab (T); 4 of them had also progressed on lapatinib (L); and one patient had progressed on T, L and T-DM1. Out of 6 breast patients with PD results available, the 3 pts with a decrease in pHER3 all responded, whereas the 3 pts with no change or increase in pHER3 all had disease progression.

Conclusion: S-222611 was well tolerated in doses up to 1600mg daily with diarrhea, nausea and rash being readily manageable. Significant antitumor activity has been observed in patients with heavily pre-treated HER2+ MBC, including those progressing on prior T, L and T-DM1. Rates of grade 3 diarrhea appear markedly lower than those reported for other second-generation pan-HER TKIs. The recommended phase 2 dose, based on PK and clinical activity, is 800mg/day.

Table 1. HER2+ MBC pts with tumor shrinkage after S-222611 treatmentPatient numberPrior progression on trastuzumab-based regimenPrior progression on lapatinib-based regimenBest responseMonths on treatment (at time of data lock)S01014YYclinical CR20.3m (ongoing)S03034YNconfirmed PR11.5m (ongoing)S04046YYconfirmed PR6.0m (ongoing)S01030YYunconfirmed PRwithdrawn at 3.7m with progressionS01047YYunconfirmed PR4.8m (ongoing)

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-12-24.

A phase I study of oral rucaparib in combination with carboplatin

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Background: Targeting poly (ADP-ribose) polymerase (PARP), an enzyme involved in DNA damage repair, may increase efficacy of DNA-damaging agents. This study evaluated the tolerability of oral rucaparib, a potent and selective PARP1/2 inhibitor, in combination with carboplatin (CP). Methods: Patients (pts) aged ≥18 with advanced solid tumors were included. Pts received lead-in doses of IV and oral rucaparib on Days -10 and -5, respectively, followed by CP on Day 1 and oral rucaparib on Days 1-14 q21 days. Treatment continued until disease progression. Pts with benefit could continue on rucaparib monotherapy once CP dosing was completed. Dose escalation was based on toxicities observed in Cycle 1 in cohorts of n=3-6. PK was assessed during Cycle 1. Results: 23 pts (median age 62 yrs [range 20 – 76]; 16 female; 9 ECOG PS=0; 6 ovarian/peritoneal cancer (OC), 5 breast cancer (BC), 2 NSCLC, 10 other tumor) were enrolled. Rucaparib doses of 80, 120, 180, 240, and 360 mg were administered with AUC3 CP, followed by 360 mg rucaparib with AUC4 CP, and currently with AUC5 CP. No DLTs have been reported. Median treatment cycles is 3 (range 1 – 15+). Treatment-related adverse events in ≥4 pts, all grades, include anemia (n=10), fatigue (n=9), nausea (n=7), thrombocytopenia (n=6), constipation (n=5), lethargy (n=5), neutropenia (n=5), and anorexia (n=4). One pt (OC, BRCAwt, AUC3 CP/180 mg rucaparib) had a PR of 5.1 mo duration. Two patients (both with OC; 1 BRCAunk, 1BRCAwt) discontinued CP (after 4 & 8 cycles) and continued on rucaparib monotherapy (additional 5 and 7+ cycles, respectively). An additional 4 pts (all BRCAunk) had stable disease (SD) >12 wks. Overall disease control rate (CR+PR+SD>12 wks) in OC pts across all dose levels was 50% (3/6). Dose-proportional increase in rucaparib exposure was observed with steady state achieved by Day 14 and mean t1/2of 15 h. Oral bioavailability was 38% and dose-independent. Rucaparib exposure was not changed by CP co-administration. Conclusions: The combination of oral rucaparib and CP is well tolerated and exhibits activity at clinically relevant doses of each agent. Further studies in platinum-sensitive and homologous recombination repair deficient populations are warranted. Clinical trial information: NCT01009190.

A phase I study of S-222611 an oral reversible dual inhibitor of EGFR and HER2, in patients with solid tumors

3100

Background: S-222611 is a novel oral, potent, reversible tyrosine kinase inhibitor with antiproliferative activity in human tumor cell lines expressing EGFR and/or HER2 in vitro and in mouse xenograft models. We conducted the first study in patients (pts) with solid tumors expressing EGFR or HER2. Methods: Daily oral doses of S-222611 were escalated in successive cohorts from 100 mg to a maximum 1600 mg, using a 3 + 3 design. Full plasma pharmacokinetic (PK) profiles were obtained in all pts for 7 days after a single dose on Day 1 and for 24 h following 21 days of once daily dosing (Cycle 1). Trough PK samples were drawn weekly during the first 3 weeks of daily dosing. A CT scan was performed at baseline and every 8 weeks post-dose to assess response (RECIST). Results: Of 23 treated pts (16 male) aged 24-77y, 19 completed Cycle 1. One dose-limiting toxicity (DLT) has been seen to date, a rash at 1200 mg, which resolved on interruption and dose reduction. Other adverse events related to drug, diarrhea, rash, and nausea, were mild (grade 1 or 2) but more frequent at higher doses. Tumor responses have been seen over a wide range of doses. One complete clinical response was observed at 1200 mg in a pt with HER2 positive breast carcinoma previously treated with lapatinib and trastuzumab. Two pts showed confirmed partial responses (one with EGFR positive renal cell carcinoma at 200 mg daily and one with EGFR and HER2 positive esophageal carcinoma at 400 mg daily); 2 pts showed unconfirmed partial responses and 3 pts (with vaginal, gastric and pancreatic adenoCa) showed stable disease for >6 months (mo); 2 pts have been treated for >12 mo. Plasma Cmax, AUC and steady state concentrations increased with dose up to 1200 mg, exceeding those eliciting maximal responses in mice. The plasma t½ is >24 h. Conclusions: S-222611 was generally tolerated well in doses up to 1200 mg, with only one DLT; rash, diarrhea and nausea have been readily manageable. PK data support once daily dosing to achieve highly effective concentrations. A substantial proportion of patients with HER2 or EGFR expressing tumors have shown partial responses or stable disease (>6 mo) and one patient has shown a complete clinical response.

Effect of the gonadotropin-releasing hormone analogue triptorelin on the occurrence of chemotherapy-induced early menopause in premenopausal women with breast cancer: a randomized trial

CONTEXT

Premenopausal patients with breast cancer are at high risk of premature ovarian failure induced by systemic treatments, but no standard strategies for preventing this adverse effect are yet available.

OBJECTIVE

To determine the effect of the temporary ovarian suppression obtained by administering the gonadotropin-releasing hormone analogue triptorelin during chemotherapy on the incidence of early menopause in young patients with breast cancer undergoing adjuvant or neoadjuvant chemotherapy.

DESIGN, SETTING, AND PATIENTS

The PROMISE-GIM6 (Prevention of Menopause Induced by Chemotherapy: A Study in Early Breast Cancer Patients-Gruppo Italiano Mammella 6) study, a parallel, randomized, open-label, phase 3 superiority trial, was conducted at 16 sites in Italy and enrolled 281 patients between October 2003 and January 2008. The patients were premenopausal women with stage I through III breast cancer who were candidates for adjuvant or neoadjuvant chemotherapy. Assuming a 60% rate of early menopause in the group treated with chemotherapy alone, it was estimated that 280 patients had to be enrolled to detect a 20% absolute reduction in early menopause in the group treated with chemotherapy plus triptorelin. The intention-to-treat analysis was performed by including all randomized patients and using imputed values for missing data.

INTERVENTIONS

Before beginning chemotherapy, patients were randomly allocated to receive chemotherapy alone or combined with triptorelin. Triptorelin was administered intramuscularly at a dose of 3.75 mg at least 1 week before the start of chemotherapy and then every 4 weeks for the duration of chemotherapy.

MAIN OUTCOME MEASURE

Incidence of early menopause (defined as no resumption of menstrual activity and postmenopausal levels of follicle-stimulating hormone and estradiol 1 year after the last cycle of chemotherapy).

RESULTS

The clinical and tumor characteristics of the 133 patients randomized to chemotherapy alone and the 148 patients randomized to chemotherapy plus triptorelin were similar. Twelve months after the last cycle of chemotherapy (last follow-up, August 18, 2009), the rate of early menopause was 25.9% in the chemotherapy-alone group and 8.9% in the chemotherapy plus triptorelin group, an absolute difference of -17% (95% confidence interval, -26% to -7.9%; P < .001). The odds ratio for treatment-related early menopause was 0.28 (95% confidence interval, 0.14 to 0.59; P < .001).

CONCLUSION

The use of triptorelin-induced temporary ovarian suppression during chemotherapy in premenopausal patients with early-stage breast cancer reduced the occurrence of chemotherapy-induced early menopause.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00311636.

Abstract 1674: The NQO1 C609T polymorphism is associated with poorer response to AC adjuvant therapy in the treatment of breast cancer

A non-synonymous SNP in the NAD(P)H: Quinone Oxidoreductase 1 gene has previously been implicated in the response of breast cancer patients to anthracycline containing regimens in a retrospective cohort study. NQO2 is 54% homologous to NQO1 at the primary protein structure and, despite the lack of a characterised endogenous electron donating cofactor for NQO2, the two enzymes share numerous substrates. NQO2, in contrast to NQO1, is additionally capable of reducing reactive quinone metabolites of estradiol. The NQO2 gene has a non-synonymous SNP that has previously been shown to result in a lower average NQO2 activity in cohorts of bladder and ovarian cancer patients. It is unknown if the NQO2 SNP impacts on survival in breast cancer.

Genomic DNA samples from 239 women with early breast cancer were genotyped for the NQO1 (rs1800566) and NQO2 (rs1143684) SNPs. All of the participants were recruited from Medical Oncology out-patient clinics within the Newcastle upon Tyne Hospitals NHS Foundation Trust and were treated with an AC adjuvant therapy regimen with curative intent. Median follow up was 78 months and followed a standard protocol. Genotyping was done by the Taqman RT-PCR method.

The NQO1 SNP was associated with a decreased time to progression (HR 2.8, 95%CI 1.4-5.64, p=0.003), decreased overall survival (HR 3.6, 95%CI 1.4-10, p=0.007) and a lower likelihood of having a dose delay, all indicative of NQO1 mediated sensitisation to the effects of doxorubicin. The NQO2 SNP had no impact on the cohort as a whole but was associated with a decreased overall survival (p=0.009, log-rank) and time to progression (p=0.004, log rank) in patients who were oestrogen receptor (ER) negative.

This study confirms the previous observation of NQO1 genotype influencing response to anthracyclines and indicates a potential impact of an NQO2 SNP on the prognosis of ER negative breast cancer. The mechanism by which NQO2 genotype influences breast survival remains to be elucidated.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1674.

Clinical Evaluation of the Use of Exemestane as Further Hormonal Therapy after Nonsteroidal Aromatase Inhibitors in Postmenopausal Metastatic Breast Cancer Patients

OBJECTIVES

The aromatase inhibitors Anastrozole, Letrozole (type 2 nonsteroidal aromatase inhibitors: n-SAI) and Exemestane (type 1 steroidal aromatase inactivator) are used respectively as first- and second-line hormonal therapy in postmenopausal metastatic breast cancer women. Few clinical data are published on the sequential use of different classes of aromatase inhibitors.

METHODS

We report an analysis on 30 postmenopausal metastatic breast cancer women treated between January 2000 and May 2002 in 2 Italian Oncology Institutions with the hormonal sequence n-SAI (Anastrozole, Letrozole) --> Exemestane.

RESULTS

When receiving n-SAI (Anastrozole 8 patients and Letrozole 22 patients), 1 out of 30 women achieved a partial response, 20 of 30 patients no change (NC) > or =6 months. The analysis of the entire population treated with Exemestane showed an overall clinical benefit (CB) of 46.6 percent (14/30) with a median duration of 12 months (95%CI 6-25) and a median time to progression (TTP) of 4 months (95%CI 1-25).

CONCLUSIONS

These data confirm a partial lack of cross-resistance between n-SAI --> Exemestane given in sequence.

Development and validation of cell-based ELISA for the quantification of trastuzumab in human plasma

Trastuzumab is a therapeutic monoclonal antibody against the Her2 oncoprotein, which is over-expressed in approximately 30% of breast cancers, and is now used routinely in the management of early and metastatic Her2+ disease. However, not all Her2+ breast cancer patients respond to trastuzumab and the pharmacodynamic and pharmacokinetic parameters behind this variation in response are unknown. Pharmacological investigations into variable response to trastuzumab have been hampered by the lack of a published feasible method to determine trastuzumab concentration in plasma. Here we describe the development and validation of a cell-based ELISA to measure trastuzumab in human plasma. The assay specifically measures the interaction between trastuzumab and Her2 and has a dynamic range of between 10 and 120 microg/ml. The mean intra-assay and inter-assay variability of the ELISA was 9%. Trastuzumab in plasma was stable for at least 10 weeks at -20 degrees C and 72 h at 4 degrees C, and was unaffected by 5 freeze/thaw cycles. Having validated the assay, the trough plasma trastuzumab concentrations of 30 patients being treated for metastatic or early disease were measured. The median trough concentration was 62 (range 21 to 441) microg/ml. This cell-based ELISA method has undergone appropriate validation and is suitable for quantification of trastuzumab in the plasma of patients treated with Herceptin.

Phase II, randomized trial of preoperative epirubicin-paclitaxel +/− gefitinib with biomarker evaluation in operable breast cancer

PURPOSE

To evaluate the in vivo effect of adding gefitinib to preoperative chemotherapy on the EGFR-dependent p42/44 MAPK in operable breast cancer (BC) patients. Secondary aims: to evaluate EGFR, (p)-EGFR, Ki67, apoptotic index (TUNEL test) and VEGFR2 expression from baseline to surgery, percentage of pathologic complete response (pCR), and toxicity.

PATIENTS AND METHODS

90 patients with stage II-IIIA BC have been randomized to receive epirubicin 90 mg/sqm and paclitaxel 175 mg/sqm on day 1 plus: gefitinib 250 mg daily from day 5 to 16 (Arm A, intermittent), gefitinib 250 mg daily from day 1 to 21 (Arm B, continuous), or placebo (Arm C). Treatment plan: 4 courses every 3 weeks, followed by surgery.

RESULTS

After preoperative therapy, 86/90 patients underwent surgery; 46 patients (51%) received breast conservative surgery. A pCR was observed in 4 patients. No significant differences in the expression of p42/44 MAPK, EGFR, (p)-EGFR, VEGFR2, proliferation index and apoptosis were observed comparing the combined Arms A + B vs C, and comparing Arm A vs B. Hematologic toxicities were not significantly different comparing Arms A + B vs Arm C, and comparing Arm A vs B. Significantly higher skin and mucosal toxicities were observed when comparing the two gefitinib Arms (A + B) vs Arm C (32% vs 9.6%, P = 0.018; 57% vs 29%, P = 0.009 respectively), while no significant differences were observed comparing Arm A vs B.

CONCLUSION

Adding gefitinib to chemotherapy did not result in different effects on the EGFR-dependent pathway, proliferation, apoptosis and VEGFR2 expression as compared to placebo, while enhancing skin and mucosal toxicity. The two schedules of gefitinib (intermittent vs continuous) did not result in different biologic effects.