Ovarian cancer patients who have an inherited BRCA mutation, and who responded to platinum-based chemotherapy, benefit from using Lynparza (olaparib) tablets as a maintenance treatment, a clinical trial suggests.
The Phase 3 SOLO-2 trial (NCT01874353) of the AstraZeneca therapy in tablet form met its primary goal of increasing patients’ progression-free survival — the length of time their disease fails to worsen. Patients on the tablets lived 13.6 months longer than those on a placebo, the trial investigators said.
The U.S. Food and Drug Administration (FDA) has approved Lynparza capsules for use against cancer, but not the tablet form yet.
Another measure of progression-free survival in the SOLO-2 trial, the Blinded Independent Central Review (BICR) scale, suggested an even larger 24.7-month improvement in the tablet takers’ progression-free survival.
The results were presented at the Society of Gynecologic Oncology Annual Meeting on Women’s Cancer March 13-15 in National Harbor, Maryland.
“The SOLO-2 data demonstrated a statistically significant and clinically meaningful improvement in outcomes for those who took olaparib,” Richard Penson, MD, associate professor of Medicine at Harvard Medical School, said in a news release.
“The results, which showed a delay in disease progression in the maintenance setting, highlight the impact of PARP inhibition at the forefront of the important advances we are making in targeting ovarian cancer,” added Penson, who is also clinical director of medical gynecologic oncology at Massachusetts General Hospital,
The trial was a randomized, double-blind, multicenter study designed to evaluate Lynparza tablets’ effectiveness as a maintenance therapy in patients with platinum-sensitive, relapsed or recurrent ovarian cancer with an inherited BRCA mutation.
The study enrolled 295 patients with a BRCA1 or BRCA2 mutation who had received at least two lines of platinum-based chemotherapy and achieved a complete or partial response. Participants were randomized to receive 300-mg Lynparza tablets, or a placebo, twice a day.
Patients taking Lynparza had a 70 percent lower risk of seeing their disease progress, the investigators found. It took 5.5 months for those on the placebo to see their disease progress, versus 19.1 months for those on Lynparza — an improvement of 13.6 months.
A BICR evaluation showed that it took 30.2 month for those on Lynparza to see their disease progress, versus 5.5 months for those on a placebo. This represented an improvement of 24.7 months — a 75 percent reduction in the risk of disease progression.
Lynparza patients also did better on another measure: time to second progression or death (PFS2). Those on placebo had a PFS2 of 18.4 months. Those on Lynparza were doing so well that investigators were actually unable to come up with a PFS2 score for them by the time of the clinical-trial analysis. That’s because fewer than half the Lynparza patients had had a second progression by the time the analysis needed to be done.
The FDA approved Lynparza capsules for women with advanced, BRCA-mutated ovarian cancer who have been treated with chemotherapy at least three times. Lynparza tablets have yet to be approved for any use, however.
Lynparza tablets proved as safe in the SOLO-2 trial as in other trials with the currently approved capsule formulation, the investigators said.
“We are extremely pleased with the results from SOLO-2, which support the potential benefit of Lynparza tablets as a maintenance therapy for patients with relapsed ovarian cancer,” said Sean Bohen, executive vice president of global medicines development and chief medical officer at AstraZeneca. “The tablet formulation may offer patients a reduced pill burden for Lynparza and a safety profile that is generally consistent with previous trials. We will work with regulatory authorities to make Lynparza tablets available to patients as quickly as possible.”