IMV‘s immunotherapy DPX-Survivac plus low-dose chemotherapy continues to show sustained benefits in people with heavily treated advanced ovarian cancer, with some benefits lasting up to 16 months, updated findings from a Phase 1/2 clinical trial show.
These data “clearly support the relevance of DPX-Survivac as a potential new and much-needed treatment option for advanced recurrent ovarian cancer, a hard-to-treat indication where other immunotherapies have thus far had limited success and where there is a high unmet medical need,” Fred Ors, president and CEO of IMV, said in a press release.
DPX-Survivac is a new type of T-cell immunotherapy that works by stimulating the immune system to target and destroy cancer cells. Specifically, it targets cancer cells that carry survivin on their surface, a protein known to promote tumor growth.
The immunotherapy, composed of small fractions of the survivin protein, is delivered as an under-the-skin injection to trigger a durable activation of T-cells (immune cells with the ability to fight cancers) against survivin-positive cancers.
The DECIDE1 trial (NCT02785250) is evaluating a combination of DPX-Survivac plus low-dose intermittent cyclophosphamide to treat women whose ovarian cancer came back after surgery and treatment with at least one chemotherapy regimen.
Its main goals are to investigate the treatment’s safety, the proportion of patients who respond to treatment, and the percentage of those attaining at least stable disease. Secondary measures include duration of responses, the time patients live without signs of disease progression, and overall survival.
Researchers will also investigate if the immunotherapy generates survivin-specific T-cells, and whether these cells are effectively entering tumors.
An earlier analysis of the first 19 patients eligible for analysis in DECIDE1 showed that about one quarter of them (26%) responded to treatment, and that an additional 53% attained disease stabilization. These clinical benefits were durable, lasting over 10 months in five patients.
All patients had been heavily treated, with a median of three prior therapies.
This update on those 19 patients found that the five women with greater clinical benefits continued to benefit from treatment for a longer period, lasting from 11 to 16 months. Two are still receiving treatment.
Additional analysis showed that about 66.1% of patients in the trial were alive after one year, and 20% were alive and without signs of disease worsening. The median time to disease progression or death was 4.5 months; as most patients were still alive, median overall survival could not be estimated.
As in the earlier analysis, the treatment was generally well-tolerated, with most treatment-related side effects being mild reactions at the injection site.
“With these results, DPX-Survivac continues to exhibit significant and durable anti-tumor activity, paving the way for targeted T cell therapies in advanced recurrent ovarian cancer and other solid tumors. DPX-Survivac also continues to be well tolerated, which is especially meaningful compared to single-agent chemotherapy and other approaches in development,” said Joanne Schindler, MD, and chief medical officer at IMV.
DPX-Survivac’s use was seen to generate circulating survivin-specific T-cells in 87% of patients. These immune cells were detected within tumors as early as 56 days (about two months) after treatment.
“IMV’s targeted T cell therapy continues to elicit a rapid and robust immune response with a demonstration that survivin-specific CD8+ T cells can infiltrate solid cancerous tumors. This could prove to be of significant interest considering that the narrowly focused action of cytotoxic CD8+ T cells allows them to kill single infected cells in tissue without creating widespread tissue damage,” Ors said.
The U.S. Food and Drug Administration (FDA) granted DPX-Survivac fast track as a maintenance therapy for advanced ovarian cancer. The potential therapy was also given orphan drug status by the FDA and the European Medicines Agency for ovarian cancer. These designations aim to support and speed the development of therapies showing promise in trials, particularly those for a rare disease.