plasmaMATCH Trial Shows Neratinib Activity in ERBB2 (HER2) Mutant Metastatic Breast Cancer - Seite 2

Approximately 1,044 patients with advanced breast cancer from approximately 20 sites in the United Kingdom registered for the trial and ctDNA results were available for 1,033 (98.9%) of the patients. Depending on the results of the ctDNA screening, patients were enrolled in one of five treatment cohorts and received therapy to target their type of breast cancer. Patients with HER2 mutations were enrolled in the cohort of patients who received either neratinib monotherapy (for patients with hormone receptor negative disease) or neratinib in combination with fulvestrant (for patients with hormone receptor positive disease). Twenty-one patients with HER2 mutations were enrolled in the cohort and 20 patients were evaluable for the primary endpoint of the trial, which was confirmed objective response rate as determined by RECIST 1.1 assessed by the investigator.

In the HER2-mutant cohort, 18 (86%) of the 21 patients had hormone receptor positive breast cancer, 18 patients (86%) had visceral disease, 18 patients (86%) had received prior chemotherapy for metastatic disease, and 11 patients (52%) had received two or more prior lines of chemotherapy for metastatic disease.

The efficacy results from the trial showed that for the 20 efficacy evaluable patients, 5 patients (25%) experienced a confirmed objective response, and three further patients had unconfirmed responses. The median duration of response was 5.7 months, and the median progression free survival in this cohort of patients was 5.4 months.

Prof. Nicholas Turner, Professor of Molecular Oncology at The Institute of Cancer Research, London, and Consultant Medical Oncologist at The Royal Marsden NHS Foundation Trust, said, “Somatic HER2 mutations can be readily and accurately identified from ctDNA blood samples and are clinically actionable for targeted therapy in metastatic breast cancers. The combination of neratinib plus fulvestrant therapy demonstrates encouraging clinical activity with durable responses in this heavily pretreated metastatic breast cancer patient population with HER2-mutated disease.”

Alan H. Auerbach, Chief Executive Officer and President of Puma Biotechnology, added, “We are very pleased with the activity seen in this cohort of patients with HER2-mutated breast cancer with neratinib in plasmaMATCH. This data correlates with the data observed in the neratinib plus fulvestrant arm of the SUMMIT trial, and we look forward to the further development of the combination of neratinib plus trastuzumab plus fulvestrant in this patient population.”