Long-term outcomes with maintenance rucaparib for BRCA+ of PALB2+ pancreatic cancer: secondary analysis of a nonrandomized trial

Secondary analysis of a phase 2 trial at Abramson Cancer Center (Philadelphia, PA) evaluated long-term outcomes with maintenance rucaparib for advanced pancreatic ductal adenocarcinoma in patients with germline or somatic pathogenic variants in BRCA1, BRCA2, or PALB2. Patients had received at least 16 weeks of platinum-based chemotherapy without evidence of platinum resistance, and received rucaparib monotherapy 600 mg orally twice daily until progression or unacceptable toxicity. Forty-two evaluable patients were enrolled, of whom 40 had metastatic disease and two had locally advanced disease. Median follow-up time was 77.9 months (range 1.3-82.7), median PFS was 12.8 months, median overall survival was 24.3 months, and objective response rate was 41.6%. Seven patients (16.7%) remained alive and progression-free for more than 5.5 years (median PFS 74.7 months; range 67.8-82.4). Of these, 4 continued receiving rucaparib and experiencing clinical remission at time of data cutoff; 3 elected to discontinue rucaparib after median 43.9 months (range 37.5-58.1). One of these 3 developed local recurrence 38 months after rucaparib discontinuation; the other 2 remained progression-free for 24.5 and 34.8 months after discontinuation. The authors conclude that more than 16% of the original trial cohort remained in clinical remission for more than 5 years receiving oral targeted therapy, while 3 patients remained progression-free without treatment for several years.