Rubraca Maintenance Delays Disease Progression in Subsequent Treatments for Recurrent OC, Phase 3 Trial Shows

Maintenance treatment with Rubraca (rucaparib) delays the need for additional treatments among women with platinum-sensitive recurrent ovarian cancer — and then extends the time to disease worsening after those subsequent therapies, a Phase 3 trial found.

The exploratory analysis from the ARIEL3 Phase 3 trial (NCT01968213) was discussed during the 2019 American Society of Clinical Oncology (ASCO) Annual Meeting, held recently in Chicago. The findings were presented in the poster, “Exploratory analysis of the effect of maintenance rucaparib on post-progression outcomes in patients with platinum-sensitive recurrent ovarian carcinoma and updated safety data from the phase 3 study ARIEL3.”

ARIEL3 included 564 women with recurrent ovarian cancer who were responding to platinum-based chemotherapy. The trial sought to determine if Clovis Oncology‘s Rubraca maintenance kept patients without disease progression for longer periods, regardless of their BRCA status.

The results showed that maintenance with Rubraca extended the time women lived without disease worsening from 5.4 months to 10.8 months. That 64% reduction in the risk of disease progression or death convinced both the U.S. Food and Drug Administration and the European Medicines Agency to approve Rubraca as a maintenance treatment for recurrent platinum-sensitive ovarian cancer.

A retrospective analysis from ARIEL3, presented at the recent International Society for Pharmacoeconomics and Outcomes (ISPOR) 2019 Meeting, continued to demonstrate the treatment’s benefits, even after weighing in patients’ perceptions about their health, disease symptoms, and treatment toxicity. In the overall population, quality-adjusted survival without disease worsening  remained significantly longer for women who received Rubraca, compared with placebo. The time period was even longer in patients with a BRCA mutation.

Now, researchers presented some exploratory measures from ARIEL3, which keep supporting the use of Rubraca as a maintenance treatment for ovarian cancer.

Among the main findings, investigators showed that Rubraca delayed the need of additional anti-cancer therapy by 57%, extending the time to first subsequent therapy from a median of 7.4 months up to 12.5 months.

The time to disease worsening or death on that subsequent treatment was also longer among those who had been given Rubraca (21.1 months) compared to a placebo (16.5 months), which eventually delayed the need for a second subsequent treatment — 22.2 months versus 18.6 months.

Consistent with prior findings, which showed Rubraca worked better among patients with mutations in BRCA genes or other genes involved in DNA repair, all these endpoints also were better in this group of women — often the patients less responsive to treatment.

BRCA-mutated patients on Rubraca only needed additional anticancer therapy 19 months after initiating the treatment, compared with 7.2 months for those on placebo. Also, their risk of disease worsening or death was reduced by 56%, compared with only 38% for the global population.

Updated safety data continues to demonstrate that Rubraca is well-tolerated and has an acceptable safety profile. The most common treatment-emergent adverse events were nausea, fatigue, abnormal taste, and anemia.

“These data positively reinforce our current clinical utilization and understanding of rucaparib as maintenance treatment for women with advanced ovarian cancer,” Robert L. Coleman, MD, professor at the University of Texas MD Anderson Cancer Center and co-coordinating investigator of ARIEL3 program, said in a press release.

“They provide further confirmation that rucaparib may help women and their physicians sustain a response to platinum-based chemotherapy,” he added.