Ovarian Cancer Drug Granted Priority Review

Progression free survival more than doubled with niraparib treatment.

The FDA recently granted priority review for the new drug application for niraparib, an investigational PARP inhibitor.

The drug is currently being evaluated for use in patients with recurrent epithelial ovarian, fallopian tube, or primary peritoneal cancers who progressed after treatment with platinum-based chemotherapy, according to a press release from Tesaro Inc.

The target action date under the Prescription Drug User Fee Act for niraparib is June 30, 2017.The FDA has no plans to have an advisory committee meeting to discuss the new drug application (NDA).

The NDA is supported by findings from the phase 3 ENGOT-OV16/NOVA clinical trial, Tesaro reported. Included in the double-blind, placebo-controlled trial were 553 patients with recurrent ovarian cancer who sustained a partial or complete response to platinum-based chemotherapy, according to the press release.

The trial assessed progression free survival (PFS) in these patients, who were grouped by germline BRCA mutation status. The findings showed that treatment with niraparib prolonged PFS compared with placebo in both patient groups, which was the trial’s primary endpoint.

Among patients with the BRCA mutation, patients treated with niraparib had a statistically significant increase in PFS compared with patients treated with the placebo. The investigators found that patients treated with niraparib had an average PFS of 9.3 months, while patients in the placebo group had a PFS of 3.9 months, according to Tesaro.

Based on these results, Tesaro proposed the use of niraparib in these patients, regardless of BRCA status. Tesaro expects that the BRCAAnalysis CDx and myChoice HRD tests would be used to confirm diagnosis, according to the press release.

Common grade 3 or 4 adverse events seen among patients taking niraparib were thrombocytopenia, anemia, and neutropenia. A majority of these adverse events occurred within the first 3 treatments, and the frequency decreased during the trial after dose modifications were made.

Tesaro plans to open an expanded access program for niraparib in January 2017. This program will allow patients with recurrent ovarian cancer following response to platinum-based chemotherapy to receive niraparib outside of clinical trials, according to the press release.

Niraparib was granted fast track designation in September 2016 by the FDA. The drug is also being tested across multiple tumor types, as well as in various combinations.

"FDA's acceptance of the niraparib NDA with a Priority Review designation is an important milestone for Tesaro, and represents a significant step in our efforts to bring meaningful therapies to women with ovarian cancer," said Mary Lynne Hedley, PhD, president and COO of Tesaro. "We believe niraparib could become an important new treatment option for patients with recurrent ovarian cancer, and we look forward to working with the FDA during the review process."