The impact of antibiotics, proton pump inhibitors, H2-receptor antagonists, and steroids on survival in ovarian cancer patients receiving PARP inhibitor therapy
Antibiotics (ABX) have been linked to reduced survival in ovarian cancer (OC) when administered before or during platinum-based chemotherapy. This study evaluates the impact of ABX, proton pump inhibitors (PPI), H2-receptor antagonists (H2RA), and steroids on progression-free survival (PFS) in OC patients receiving poly-ADP-ribose polymerase inhibitors (PARPi). This retrospective study examined OC patients who used ABX, PPI, H2RA, or steroids before or during PARPi therapy. Demographics, clinicopathologic characteristics, and treatment outcomes were analyzed. Cox proportional hazards models assessed risk factors for PFS, and Kaplan-Meier analysis with log-rank testing evaluated survival differences based on ABX use. Among 237 patients treated with 269 PARPi regimens, most received PARPi in the recurrent setting (79.6 %). At the time of PARPi therapy, 21.6 % used ABX, 15.6 % PPI, 11.2 % H2RA, and 63.9 % steroids. Patients with HRP/unknown status had significantly worse median PFS than those with BRCA-mutated/HRD (6 vs. 11 months; p < 0.001). ABX use correlated with improved median PFS (10 vs. 7 months; p = 0.049) but lost significance in multivariate analysis. PPI, H2RA, and steroids had no impact on PFS. In this retrospective analysis, concurrent medications were not associated with worsened survival outcomes in OC patients receiving PARPi. Further, while ABX use during PARPi therapy was associated with improved survival this was not significant after adjusting for confounders.