OncoPep announced the initiation of a Phase 1b clinical trial evaluating its investigational vaccine product PVX-410 for the treatment of patients with metastatic triple negative breast cancer (TNBC) who are human leukocyte antigen A2 positive (HLA-A2+). The investigator-sponsored study led by Steven Isakoff, M.D., Ph.D., at Massachusetts General Hospital, will assess the safety, tolerability and immune response to PVX-410 alone and in combination with the checkpoint inhibitor pembrolizumab (Keytruda, Merck). PVX-410 is a multi-peptide investigational therapeutic cancer vaccine which may act to help stimulate an immune response against cancer cells.
“This study will help determine if PVX-410 and pembrolizumab administered together can help the body's immune system to recognize and potentially reduce or stabilize tumors in patients with metastatic triple negative breast cancer,” said Dr. Isakoff, Associate Director for Breast Cancer Clinical Research at the Massachusetts General Hospital Cancer Center and Assistant Professor in Medicine at Harvard Medical School. “TNBC continues to be a disease with poor prognosis that disproportionally affects premenopausal women and African-American women and new treatment options beyond chemotherapy are desperately needed. I am pleased to be involved with this research initiative and look forward to assessing PVX-410 in this unique combination."
The open label, multi-center Phase 1b study is designed to evaluate the safety and immune response to PVX-410 alone and in combination with pembrolizumab in HLA-A2+ patients with metastatic TNBC. Patients will receive weekly injections of PVX-410 for six consecutive weeks, followed by booster PVX-410 vaccine doses at Week 10 and Week 28. Pembrolizumab will be administered every three weeks intravenously starting with Week 1. The trial is expected to enroll a total of approximately 20 patients at multiple trial sites, including Massachusetts General Hospital, Beth Israel Deaconess Medical Center and the Dana Farber Cancer Institute. More information on the trial can be found at clinicaltrials.gov, identifier number NCT03362060.
Triple negative breast cancer (TNBC) is a form of breast cancer that lacks the three receptors found most commonly on breast cancer cells: estrogen receptor (ER), progesterone receptor (PR), and hormone epidermal growth factor receptor 2 (HER-2). TNBC accounts for approximately 15-20% of all breast cancer cases and is more likely to spread and recur than other forms of breast cancer. TNBC disproportionally affects premenopausal women and African-American women. Patients diagnosed with metastatic TNBC have a median survival of just over 1 year, and patients with early stage TNBC have a median 5-year survival of 77% compared to 93% for non-TNBC. Residual disease after neoadjuvant chemotherapy (non-pathologic complete response) predicts a poor prognosis with nearly half of such patients experiencing a recurrence within 5 years.
PVX-410 is a novel investigational therapeutic cancer vaccine currently in Phase 1b clinical trials in smoldering multiple myeloma and triple negative breast cancer. PVX-410 consists of four peptides from unique regions of three tumor -associated antigens which may act to help stimulate an immune response to the targeted tumor cell. PVX-410 was granted orphan drug designation from the U.S. Food and Drug Administration in 2013 for the treatment of multiple myeloma.