A phase II study of efficacy, toxicity, and the potential impact of genomic alterations on response to eribulin mesylate in combination with trastuzumab and pertuzumab in women with human epidermal growth factor receptor 2 (HER2)+ metastatic breast cancer.

PURPOSE: There are limited data on trastuzumab-pertuzumab (HP)-based treatments beyond the first-line, HER2+ metastatic breast cancer (MBC) setting. We conducted a phase II study of eribulin mesylate, which extends survival in MBC, with HP in patients with previously treated HER2+ MBC to evaluate efficacy, toxicity, and genomic alterations driving therapeutic response. METHODS: After a run-in phase for eribulin dosing, two cohorts were enrolled (Cohort A-no prior pertuzumab; Cohort B-prior pertuzumab). All patients received eribulin 1.4 mg/m2 on days 1, 8 with standard-dose HP on day 1 (21-day cycles). The primary endpoint was objective response rate (ORR). Genomic characterization via whole exome sequencing (WES) was completed on tumor DNA and matched germline DNA from 19 patients. RESULTS: The six-patient run-in established a dose of eribulin 1.4 mg/m2 with HP. Cohorts A and B enrolled 17 and 7 patients, respectively. Accrual stopped early due to an evolving treatment landscape and slow enrollment. The ORR was 26.3% (95% Confidence Interval [CI] 9.2-51.2%) in Cohort A and 0% in Cohort B (95% CI 0-41.0%). WES revealed more frequent alterations in TP53 (p < 0.05, q > 0.05) in patients without clinical benefit (disease control for < 24 weeks) which was not significant after multiple hypothesis correction. CONCLUSION: Eribulin-HP had manageable toxicity and modest clinical activity in patients without prior pertuzumab exposure. This study provides a preliminary landscape of somatic alterations in this patient cohort. Our data add to the literature on how genomic alterations may predict for therapy response/resistance, as we work to individualize choices in a quickly evolving HER2+ MBC treatment landscape. TRIAL REGISTRATION: www.clinicaltrials.gov , NCT01912963. Registered 24 July 2013.

A patient-driven clinicogenomic partnership for metastatic prostate cancer.

Molecular profiling studies have enabled discoveries for metastatic prostate cancer (MPC) but have predominantly occurred in academic medical institutions and involved non-representative patient populations. We established the Metastatic Prostate Cancer Project (MPCproject, mpcproject.org), a patient-partnered initiative to involve patients with MPC living anywhere in the US and Canada in molecular research. Here, we present results from our partnership with the first 706 MPCproject participants. While 41% of patient partners live in rural, physician-shortage, or medically underserved areas, the MPCproject has not yet achieved racial diversity, a disparity that demands new initiatives detailed herein. Among molecular data from 333 patient partners (572 samples), exome sequencing of 63 tumor and 19 cell-free DNA (cfDNA) samples recapitulated known findings in MPC, while inexpensive ultra-low-coverage sequencing of 318 cfDNA samples revealed clinically relevant AR amplifications. This study illustrates the power of a growing, longitudinal partnership with patients to generate a more representative understanding of MPC.