219 Background: Inhibition of poly adenosine diphosphate ribose polymerase (PARP) enzymes terminates an alternative DNA repair pathway, resulting in synthetic lethality in homologous recombination deficient tumors. Many PARP inhibitors have shown to improve survival in many solid tumors with noteworthy safety concerns. We undertook a systematic review and meta-analysis of randomized controlled trials (RCT) to determine the risk of gastrointestinal (GI) and hepatic toxicities. Methods: We conducted a comprehensive literature search using MEDLINE, EMBASE databases and meeting abstracts from inception through June 2018. Phase III RCTs that mention GI toxicities and elevation of aspartate aminotransferase (AST) or alanine aminotransferase (ALT) as adverse effects were incorporated in the analysis. Mantel-Haenszel (MH) method was used to calculate the estimated pooled risk ratio (RR) with 95% confidence interval (CI). Random effects model was applied. Results: 3188 patients from 7 phase III RCTs with breast, ovarian and gastric cancer were eligible. Studies compared olaparib or niraparib or rucaparib versus placebo, olaparib versus single agent chemotherapy, iniparib + gemcitabine / carboplatin (GC) versus GC, veliparib + C versus C and olaparib + paclitaxel versus paclitaxel. The RR of all-grade side effects were as follows: diarrhea, 1.24 (95% CI: 1.08 – 1.42, P = 0.002); nausea, 1.53 (95% CI: 1.16 – 2.02, P = 0.002); vomiting, 1.46 (95% CI: 1.02 – 2.08, P = 0.03); elevated AST, 1.25 (95% CI: 0.58 – 2.67, P = 0.55); and elevated ALT, 1.61 (95% CI: 0.81 – 3.20, P = 0.16). The RR of high-grade side effects were as follows: diarrhea, 1.08 (95% CI: 0.52 – 2.24, P = 0.82); nausea, 1.81 (95% CI: 0.79 – 4.12, P = 0.15); vomiting, 1.99 (95% CI: 1.06 – 3.73, P = 0.03); elevated AST, 1.86 (95% CI: 0.45 – 7.55, P = 0.38); and elevated ALT, 1.33 (95% CI: 0.42 – 4.18, P = 0.62). Conclusions: Our study showed that the risk of developing all grades of vomiting as well as any-grade nausea and diarrhea was high in PARP inhibitors arm, compared to control group. Timely recognition and prompt intervention with good supportive care are entailed.
Poly(adenosine diphosphate ribose) polymerase inhibitors induce autophagy‐mediated drug resistance in ovarian cancer cells, xenografts, and patient‐derived xenograft models
