Bermuda-based Sellas Life Sciences Group will conduct a Phase 3 clinical trial to investigate the efficacy and safety of the galinpepimut-S vaccine as a potential treatment for patients with malignant pleural mesothelioma (MPM).
The galinpepimut-S vaccine targets the WT1 protein, which is widely expressed in multiple cancer malignancies and considered a crucial target for cancer therapy. Previous Phase 1 and Phase 2 clinical trials have shown that galinpepimut-S induces a strong T-cell immune response against cancer cells producing this protein, thereby avoiding cancer relapse in patients who underwent surgical removal of their cancers.
Indeed, results of a Phase 2 trial with 40 MPM patients (NCT01890980), presented at the 2016 Annual Meeting of the American Society of Clinical Oncology and the 2016 International Mesothelioma Interest Group, showed that galinpepimut-S induced a median overall survival of 24.8 months, whereas patients treated with a placebo had an overall survival of only 16.6 months.
Patients tolerated galinpepimut-S, which activated CD8+ and CD4+ T-cells and significant improved the survival of patients with complete tumor removal.
Based on these positive results, in September 2016, the U.S. Food and Drug Administration (FDA) granted Fast Track designation to galinpepimut-S to hasten the drug’s development as a possible treatment for MPM.
The Phase 3 trial is expected to start this year. Mesothelioma Research News interviewed Angelos Stergiou, MD, ScD, CEO and vice chairman of the board; and Nicholas Sarlis, MD, PhD, senior vice president and chief medical officer of Sellas, to learn more about the upcoming study.
“In our phase 3 clinical trial, we plan to include patients with mesothelioma with disease on one side of the chest (right or left) who would have been able to complete initial treatment with surgery and chemotherapy,” Stergiou and Sarlis told us. “We are hoping to enroll a minimum of 150 patients, but the study could potentially include up to 400 patients, depending on whether certain criteria are met when we ‘look’ at pre-set intervals on how the study evolves.”
Stella plans to actively treat each patient for at least 13 to 18 months. According to Stergiou and Sarlis, the clinical benefit induced by galinpepimut-S will be measured by overall survival by study’s end, but the trial will also measure time to disease relapse and rate of progression in patients. They estimate that patients receiving galinpepimut-S will live least eight months longer than those treated with standard therapy.
“Galinpepimut-S is designed to act exactly during the period of high risk for recurrence and could significantly delay the re-occurrence of the disease but, more importantly from what we have seen, it seems to prolong survival; this could be translated into an at least eight-month benefit in additional lifespan,” they said. “Given … the complete lack of an effective maintenance therapy to prevent tumor relapses, as well as the very favorable safety profile of galinpepimut-S … we believe that MPM patients (and their treating physicians) would be very interested in participating in our trial.”
Importantly, the study is designed to provide results as soon as possible. “[I]f there are early indications of clinical benefit with regard to overall survival and/or delayed progression-free survival by giving galinpepimut-S, this could lead to stopping at the second interim analysis and declaring the study as ‘positive’,” they said.
To know more details about the upcoming clinical trial and other ongoing trials of galinpepimut-S, read the complete interview here.