The Phase 1b/2 trial investigating IMV lead candidate DPX-Survivac in combination with Incyte‘s experimental epacadostat and low-dose chemotherapy in recurrent ovarian cancer patients has completed patient enrollment in the study’s first part, the companies announced. It also dosed the first patient in the trial’s second part.
“Completion of the Phase 1b enrollment and initiation of the Phase 2 component of our clinical program are key milestones in our goal to accelerate the clinical evaluation and path to market of our novel immuno-therapy,” Frederic Ors, the CEO of IMV, said in a press release.
“We are very pleased to be able to continue to make substantial progress for advanced ovarian cancer patients who have such a high unmet medical need,” he added.
DPX-Survivac consists of small fractions of the survivin protein, which is broadly over-activated in most cancer types and promotes tumor growth, according to IMV. Survivin plays an essential role in supporting tumor blood vessel growth and promoting resistance to anti-cancer therapies.
The therapy, administered as an injection under the skin, works by triggering a strong immune response against cancer cells producing the survivin protein, causing them to die.
Epacadostat is a potent, selective oral IDO1 inhibitor. Belonging to the growing class of checkpoint inhibitors, such as CTLA-4, PD-1, and PD-L1 antibodies, IDO pathway inhibitors can regulate immune responses by suppressing tumor cell survival, growth, and invasion.
The Phase 1b part of the trial (NCT02785250) was designed to test a combination of DPX-Survivac, epacadostat and low-dose cyclophosphamide in ovarian cancer patients who received surgery and any number of prior chemotherapies.
The trial included 50 patients who received one of two epacadostat doses — 100 mg or 300 mg — along with the other two therapies.
Early data from the first 10 patients examined showed that 70% of the women receiving the 100 mg dose of epacadostat achieved at least disease stabilization. Three of these patients had partial responses.
A blood analysis revealed the treatment activated immune T-cells, which correlated with signs of tumor shrinkage. The combination also exhibited a tolerable safety profile.
Topline results from the Phase 1b study are expected by the end of 2018.
Based on the promising results, IMV and Incyte decided to expand their collaboration and extend the trial to include a Phase 2 part. Their goal was to understand how each therapy contributes to the effectiveness of the combination. The Phase 2 trial is currently recruiting participants and expects to include 32 additional patients.