I/O Vaccine Maveropepimut-S Shows Encouraging Results in Advanced Recurrent Ovarian Cancer

Oliver Dorigo, MD, PhD

Outcomes in patients with advanced recurrent ovarian cancer treated with the novel immunotherapeutic vaccine maveropepimut-S (formerly DPX-Survivac) appeared encouraging, according to topline results from the DeCidE1 clinical trial, announced by IMV, Inc, in a press release.¹

Maveropepimut-S brings together the advantages of the DPX platform advantages and the cancer antigen survivin, which is represented in more than 15 solid tumors and hematologic malignancies, according to the developer. Through infiltrating targeted T cells into tumors following therapy, maveropepimut-S has been able to induce robust and long-lasting immune responses. The responses with the agent can last up to 2 years.²

In DeCidE1 (NCT0278525), maveropepimut-S achieved a median overall survival (OS) of 19.9 months and at 23.8 months, the OS rate was 44.9%. After more than 2 years of clinical benefit derived from the therapy, the final patients completed treatment in the study, and investigators were able to confirm translational analyses of tumor-antigen directed T cells by maveropepimut-S.¹

The overall results obtained from the DeCidE1 trial are very promising,” Oliver Dorigo, MD, PhD, principal investigator of the DeCidE1 study and director of the Gynecologic Oncology Service at Stanford University stated, in the press release… “These results are particularly encouraging because many subjects in the trial had been heavily pre-treated and 57.9% were platinum-resistant. We believe that these results support the further clinical study of maveropepimut-S in ovarian cancer.”

DeCidE1 is a phase 1b/2 study which is primarily exploring the safety of maveropepimut-S as determined by adverse events and the phase 2 objective response rate (ORR) in approximately 85 patients with advanced recurrent ovarian cancer. The secondary end points of the study include ORR in each treatment group per RECIST v1.1, duration of response, cell-mediated immunity as measured by the antigen-specific response in peripheral blood, treatment-induced changes in tumor-infiltrating lymphocytes time to progression, and overall survival (OS).

Patients enrolled in DeCidE1 were required to have histologically confirmed stage IIc-IV epithelial ovarian, fallopian tube or peritoneal cancer, be platinum-resistant or platinum-sensitive following frontline therapy, have progressive disease, measurable disease, be ambulatory with an ECOG performance status of 0 o 1, have a life expectancy of at least 6 months, and have adequate laboratory results at baseline screening.

The study excluded individuals who were eligible for curative therapy or undergoing concurrent therapy previously received maveropepimut-S. Patients who had concurrent secondary malignancy aside from non-melanoma skin cancer, cervical cancer, or controlled bladder cancer, had clinical ascites, a lesion greater than 4 cm, a history of autoimmune disease that required treatment within the past 2 years, malignant bowel obstruction, and other condition that may have interfered with treatment were also ineligible to enroll.

Information from the translational analyses of DeCidE1 have been submitted for presentation at an upcoming medical meeting.

“The translational analyses provide strong evidence that maveropepimut-S successfully elicits the generation of tumor antigen-specific T cells. Importantly, these analyses affirm the molecular and cellular mechanism of MVP-S based therapy. This data will also inform the discussion and design of a phase 2 clinical study to be submitted to the FDA, said Jeremy Graff, PhD, in the press release.

_References:

_{1. IMV announces final topline results of the DeCidE1 clinical trial in advanced recurrent ovarian cancer. News release. IMV, Inc. August 10, 2021. Accessed August 11, 2021. https://bit.ly/3iCe3LP}

_{2. Maveropepimut-S (DPX-Survivac). IMV, Inc website. Accessed August 11, 2021. https://bit.ly/2Xi3nd4}