Eligibility for First-Line PARP Inhibitor Maintenance in Advanced Ovarian Cancer

Many patients with advanced ovarian cancer may be eligible for first-line maintenance with a PARP inhibitor, according to research published in Cancer.

Researchers also found that patients treated with bevacizumab and those who have BRCA mutations are likely to have better outcomes.

The researchers conducted this trial, the RESPONSE trial, to characterize real-world treatment patterns and outcomes of patients with newly diagnosed, advanced high-grade serous or endometrioid ovarian cancer.

The researchers collected data from medical records for ovarian cancer patients from 8 countries (Austria, Belgium, Denmark, Finland, Israel, Netherlands, Norway, and Portugal). The patients were diagnosed no later than April 1, 2018 (index date), when PARP inhibitors were not yet commercially available. Patients were selected backward in time from the index date and followed for at least 20 months.

At total of 1119 patients were included in the study. Their median age was 66 (range, 57-73) years. Most patients (97.5%) had high-grade serous histology, 66.9% had stage III disease, and 11.6% had a deleterious germline BRCA mutation.

Most patients (92.9%) had received chemotherapy, 26.6% had received bevacizumab, 40.8% had primary debulking surgery (PDS), and 39.3% had interval debulking surgery (IDS). No visible residual disease was observed in 55.5% of patients who underwent PDS and 63.9% of patients who underwent IDS.

Physician-assessed responses to first-line chemotherapy following surgery indicated that 53.2% of the cohort had a complete response (CR), and 25.7% had a partial response (PR).

Based on these figures (CR and PR rate), the researchers estimated that 78.9% of patients would potentially have been eligible for PARP inhibitor maintenance.

After at least 20 months of follow-up, 32.9% of patients were disease-free, 46.4% had progressive disease, and 20.6% had died.

The researchers found that bevacizumab had a significant positive effect on overall survival (hazard ratio [HR], 0.62; 95% CI, 0.42-0.91; P =.01), and the presence of a BRCA mutation had a significant positive effect on progression-free survival (HR, 0.60; 95% CI, 0.41-0.84; P <.01).

Despite these benefits, the researchers noted that, overall, the outcomes in this study “highlight the poor prognosis of this population and the urgent need for better treatments.”

Disclosures: This research was supported by AstraZeneca as part of an alliance between AstraZeneca and Merck Sharp & Dohme Corp. Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of disclosures.

Reference

Marth C, Abreu MH, Andersen KK, et al. Real-life data on treatment and outcomes in advanced ovarian cancer: An observational, multinational cohort study (RESPONSE trial). Cancer. Published online June 17, 2022. doi:10.1002/cncr.34350

This article originally appeared on Cancer Therapy Advisor