Olaparib as maintenance therapy in non resectable pancreatic adenocarcinoma associated with homologous recombination deficiency profile: A French retrospective multicentric AGEO real-world study.

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) has a poor prognosis. The POLO trial showed that olaparib (PARP inhibitor) improved progression-free survival (PFS) but not overall survival (OS), when used as maintenance therapy after ≥ 16 weeks of disease control with first-line platinum-based chemotherapy in patients with germline (g) BRCA 1 or 2 pathogenic variants (PV) metastatic PDAC. However, real-world data on the effectiveness of olaparib are missing.

METHODS

Patients with unresectable PDAC associated with somatic (s) or (g)BRCA1/2 and (g)non-BRCA-HRD PV (i.e. other homologous recombination deficiency/HRD genes) who were treated with olaparib between 2020-2023 were included. The primary objective was to describe treatment patterns. Secondary exploratory objectives included OS and PFS in patients treated with olaparib according to the POLO trial or not, OS and PFS in patients with (g)HRD PV-associated PDAC versus (s)PVs, olaparib safety profile and factors associated with olaparib poor outcomes.

RESULTS

Among 85 patients, 45.9 % received olaparib as defined by the POLO trial. No difference in OS and PFS was observed between patients who received olaparib according to the POLO trial versus not. Patients with (g)HRD PV-associated PDAC had better OS compared to others (22.3 versus 10.5 months, p = 0.038). Factors associated with olaparib poor outcomes included a high neutrophil-to-lymphocyte ratio and the use of olaparib outside the recommendations of the POLO trial. Few grade ≥ 3 adverse events were reported (9.4 %).

CONCLUSION

Patients with (g)HRD PV-associated PDAC had longer OS than those with (s)HRD PV. Olaparib use beyond the scope of the POLO trial was associated with poor outcomes.