Rucaparib Maintenance Demonstrates Durable 5-Year Benefit in Ovarian Cancer

By: Wendy LaGrego
Posted: Monday, March 2, 2026

Long-term follow-up data from the phase III ATHENA-MONO/GOG-3020/ENGOT-ov45 trial further establish rucaparib as an effective first-line maintenance option for patients with newly diagnosed advanced ovarian cancer, regardless of homologous recombination deficiency (HRD) status. The analysis, led by Rebecca S. Kristeleit, MD, of Guy’s and St Thomas’ NHS Foundation Trust and Comprehensive Cancer Center, King’s College London, was published in Annals of Oncology and reports updated efficacy and safety outcomes with a median follow-up approaching 5 years.

Study Details

ATHENA-MONO is a multicenter, randomized, double-blind, placebo-controlled phase III trial evaluating rucaparib monotherapy as maintenance treatment following response to front-line platinum-based chemotherapy. Between October 2018 and September 2020, patients with stage III or IV high-grade epithelial ovarian, fallopian tube, or primary peritoneal cancer were randomly assigned in a 4:1 ratio to receive rucaparib (n = 427) or placebo (n = 111) for up to 24 months. Stratification factors included HRD status, residual disease after chemotherapy, and timing of surgery. The primary endpoint was investigator-assessed progression-free survival in the HRD intent-to-treat (ITT) populations.

Key Takeaways

With a median progression-free survival follow-up of approximately 59 months, rucaparib continued to demonstrate a significant and durable progression-free survival advantage compared with placebo. In the HRD population, median progression-free survival was 31.4 months with rucaparib vs 12.0 months with placebo (hazard ratio [HR] = 0.52, 95% confidence interval [CI] = 0.35–0.76). In the ITT population, median progression-free survival was 20.2 months with rucaparib vs 9.2 months with placebo (HR = 0.53, 95% CI = 0.42–0.69).

Benefit was observed across clinically relevant subgroups, including patients without HRD. Among patients considered at higher risk of recurrence, nearly one-quarter of those treated with rucaparib remained progression-free at 5 years, compared with fewer than 10% in the placebo arm. These findings highlight the potential for long-term disease control beyond completion of the 24-month treatment period.

The safety profile of rucaparib with extended follow-up was consistent with prior analyses. The most common treatment-emergent adverse events included nausea, fatigue, anemia, and transient elevations in liver enzymes. Most events were grade 1 or 2 and manageable with dose modifications. No new safety signals emerged, and the incidence of myelodysplastic syndrome or acute myeloid leukemia remained low, at approximately 1.4%.

“In conclusion, 5-year follow-up data from ATHENA-MONO continue to support rucaparib monotherapy as a durable and efficacious first-line maintenance treatment with a manageable safety profile in a broad patient population with advanced ovarian cancer, regardless of HRD status,” the authors stated.

DISCLOSURE: For full disclosures of all study authors, visit annalsofoncology.com.

Annals of Oncology

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