EpiThany says it will test its multi-antigen vaccine EP-101 STEMVAC — in combination with the PD-L1 antibody Bavencio (avelumab) — as a neoadjuvant therapy in breast cancer patients, under a three-way agreement with Pfizer and Merck (EMD Serono in the United States and Canada).
The combination therapy will be assessed in a randomized, double-blind, placebo-controlled Phase 2 trial. EP-101 contains pieces of the CD105, Yb-1, SOX2, CDH2 and MDM2 proteins, and is designed to activate robust T-cell responses against cancer cells expressing these proteins.
“The evaluation of our lead product candidate EP-101 in combination with avelumab in this randomized Phase 2 trial will build upon our compelling preclinical and early clinical data highlighting the potential benefits of Th-1 selective vaccination in women with breast cancer,” Bill Watt, EpiThany’s founder, president and CEO, said in a press release.
The vaccine is currently being evaluated in a Phase 1 trial (NCT02157051) for patients with HER2-negative advanced breast cancer.
The new Phase 2 trial will assess EP-101’s immunological efficacy, clinical activity and safety in combination with Bavencio and standard-of-care therapies, as a neoadjuvant therapy — meaning that women with breast cancer will receive it before their surgery. The trial, to begin in early 2018, will enroll up to 84 women who will be randomized to receive EP-101 or a placebo.
“Despite advances in treatment for these patients over recent years, response rates remain low and chance of recurrence is high,” said Dr. Alise Reicin, head of global clinical development at Merck’s biopharma business in Darmstadt, Germany. “This collaboration with EpiThany to evaluate a Th-1 selective vaccine in combination with avelumab allows us to explore a potential synergistic immuno-oncology treatment regimen that may provide improved outcomes for women with this common form of breast cancer.”
Added Dr. Chris Boshoff, senior vice-president and head of immuno-oncology, early development and translational oncology at Pfizer: “A key focus of our clinical development program for avelumab is to evaluate the role and potential of combination therapy in immuno-oncology. Through this collaboration with EpiThany, we look forward to assessing and understanding the benefits that the combination of avelumab and EP-101 may offer as a treatment option for patients with breast cancer.”
The U.S. Food and Drug Administration granted Bavencio accelerated approval in March 2017 to treat certain patients with metastatic Merkel cell carcinoma or metastatic bladder cancer, but the drug has not yet been proven safe and effective for the treatment of breast cancer patients.