Positive Phase II Results Reported for Ovarian Cancer Vaccine
Time to recurrence more than double that of standard treatment (May 15)
In a randomized phase II trial, a tumor-based personalized cancer vaccine (FANG; Gradalis, Inc.) elicited an immune response and delayed the time to recurrence in patients with advanced-stage ovarian cancer by more than 1 year compared with patients who received standard of care.
An interim analysis of the study findings will be presented at the 16th Annual Meeting of the American Society of Gene and Cell Therapy, to be held May 15–18 in Salt Lake City, Utah.
The phase II trial enrolled 17 patients with stage IIIc or stage IV ovarian cancer — the most advanced stages of the disease, in which the cancer has spread to other organs. Twelve patients received the FANG personalized vaccine plus standard treatment, and five patients received only standard treatment, which consisted of tumor removal and chemotherapy. The study’s primary endpoint was the time to disease recurrence.
At the interim analysis, a positive tumor immune response, as measured by enzyme-linked immunospot (ELISPOT) analysis, was observed in 71% of the patients treated with the FANG vaccine. The mean time to recurrence from the start of treatment for patients receiving the vaccine was 470 days compared with 193 days for the group receiving standard of care.
In a previous phase I study, long-term follow up of 32 patients with various types of late-stage cancer who received the FANG vaccine showed a median survival of 562 days compared with 86 days for 23 patients who chose to receive other treatments (P < 0.000001). Based on an analysis of risk factors derived from a database of 1,181 patient assessments from the MD Anderson Cancer Center, the expected survival for patients enrolled in the FANG clinical study was between 6.2 and 8.4 months. Treatment with the FANG vaccine therefore more than doubled the overall survival time to 18.7 months for patients with advanced cancer who had an otherwise poor prognosis.
The personalized vaccine is manufactured from a cell suspension derived from a marble-sized portion of the patient’s tumor, removed during surgery. A plasmid that expresses the immune activator GM-CSF (granulocyte macrophage colony-stimulating factor) and a proprietary RNA construct against furin is introduced into the tumor cells by electroporation. The cells are then incubated overnight, irradiated, and frozen. The vaccine is shipped to the patient’s clinic, where doses are thawed and administered monthly by intradermal injection.
Source: Gradalis, Inc.; May 15, 2013.