Olaparib Effective Maintenance Therapy for Germline BRCA-Mutated Pancreatic Cancer

For patients with metastatic pancreatic cancer with a germline BRCA mutation who are responding to or stable on platinum-based chemotherapy, the PARP inhibitor olaparib was approved as maintenance therapy based on improved progression-free survival (PFS) reported in the POLO trial (NEJM JW Oncol Hematol Jun 26 2019; [e-pub] and N Engl J Med 2019; 381:317). Investigators now report an update of this industry-sponsored phase 3 trial in which 92 patients were randomized to olaparib and 62 to placebo.

At a median follow-up of 31.3 months for the olaparib group and 23.9 months for the placebo group, the hazard ratio (HR) for overall survival (OS) trended numerically but not statistically superior for olaparib versus placebo (HR, 0.83; P=0.3487), with similar median OS (19.0 and 19.2 months). At 36 months, OS was 33.9% for olaparib compared with 17.8% for placebo, and a higher percentage of patients were still receiving olaparib (14.1%) compared with placebo (3.2%). Updated PFS (the primary endpoint) was superior for olaparib compared with placebo, with a median PFS of 6.7 versus 3.7 months (HR, 0.49; P=0.0004) and estimated 3-year PFS of 23.1% versus 5.4%. The median duration of treatment was 25.9 months for olaparib compared with 7.3 months for placebo. No new safety signals were observed and there were no cases of myelodysplastic syndrome or acute leukemia.