The following article features coverage from the SGO 2022 Annual Meeting on Women’s Cancer. Click here to read more of Cancer Therapy Advisor’s conference coverage.

Final data from the SOLO3 trial support the use of olaparib in patients with heavily pretreated, germline BRCA-mutant, platinum-sensitive, relapsed ovarian cancer, according to researchers.

Olaparib did not improve overall survival (OS) or the time from randomization to second progression or death (PFS2), when compared with physician’s choice of chemotherapy.

However, olaparib did improve the time to subsequent treatment and time to discontinuation or death.


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These results were presented at the SGO 2022 Annual Meeting on Women’s Cancer by Richard Penson, MD, of Massachusetts General Hospital in Boston.

The SOLO3 trial (ClinicalTrials.gov Identifier: NCT02282020) included 266 patients with germline BRCA-mutant, platinum-sensitive, relapsed, high-grade serous or endometrioid ovarian, primary peritoneal, and/or fallopian tube cancer.

The patients were randomly assigned 2:1 to receive olaparib at 300 mg twice daily or single-agent non-platinum chemotherapy of the physician’s choice. Patients were treated until disease progression.

In the primary analysis, olaparib improved the objective response rate (ORR) and progression-free survival (PFS) compared with chemotherapy.

The ORR was 72.2% with olaparib and 51.4% with chemotherapy (odds ratio, 2.53; P =.002). The median PFS was 13.4 months and 9.2 months, respectively (hazard ratio [HR], 0.62; P =.013).

Final Results

At the final analysis, there was no significant difference in OS between the treatment arms. The median OS was 34.9 months in the olaparib arm and 32.9 months in the chemotherapy arm (HR, 1.07, P =.714).

Dr Penson noted that 11% of patients in the olaparib arm and 25% in the chemotherapy arm left the study before death, and the survival status of some of these patients is unknown.

Dr Penson pointed out that PFS2 slightly favored olaparib, but the difference with chemotherapy was not statistically significant. The median PFS2 was 23.6 months with olaparib and 19.6 months with chemotherapy (HR, 0.80; P =.229).

On the other hand, olaparib significantly delayed the time to first subsequent therapy (TFST), time to second subsequent therapy (TSST), and time to discontinuation or death.

The median TFST was 15.4 months with olaparib and 10.9 months with chemotherapy (HR, 0.49; P <.001). The median TSST was 25.2 months and 19.9 months, respectively (HR, 0.75; P =.089).

The median time to discontinuation or death was 13.1 months with olaparib and 5.1 months with chemotherapy (HR, 0.20; P <.001).

Dr Penson said no new safety signals were identified in this update. Fewer patients in the olaparib arm than in the chemotherapy arm discontinued treatment due to adverse events (10.1% and 19.7%, respectively).

“Our results support the use of olaparib as a chemotherapy-free treatment option in heavily pretreated patients,” Dr Penson concluded.

Disclosures: Dr Penson disclosed relationships with AbbVie, AstraZeneca, Cancer Panels, Care4ward, Merck & Co., Roche Pharma, Sutro Biopharma, GSK Inc., Vascular Biogenics Ltd, WebMD, Array BioPharma Inc., Eisai Inc., Genentech, Inc., Regeneron, Sanofi-Aventis US LLC, Tesaro Inc., Vascular Biogenics Ltd, BMJ Publishing, UptoDate, Elsevier Ltd., Wolters Kluwer Health, and Wiley Blackwell.

Read more of Cancer Therapy Advisor’s coverage of SGO 2022 by visiting the conference page.

Reference

Penson RT, Valencia RV, Colombo N, et al. Final overall survival results from SOLO3: Phase III trial assessing olaparib monotherapy versus non-platinum chemotherapy in heavily pretreated patients with germline BRCA1 and/or BRCA2-mutated platinum-sensitive relapsed ovarian cancer. Presented at SGO 2022; March 18-21, 2022. Abstract 26.