PARP-inhibitor potpourri: A comparative review of class safety, efficacy, and cost

To summarize similarities and differences in efficacy, safety, and cost of available PARP-inhibitors and offers pearls to distinguish subtle nuances between each agent to help guide therapy.

Currently, four PARP-inhibitors (olaparib, rucaparib, niraparib, and talazoparib) are FDA-approved, with olaparib, rucaparib, and niraparib approved for treatment and/or maintenance or ovarian cancer and olaparib and talazoparib approved for the treatment of recurrent metastatic BRCA-mutant, HER2-negative breast cancer. While the PARP-inhibitor class is generally are well-tolerated, each agent does possess a unique side-effect profile. Niraparib and talazoparib have more prominent hematologic adverse event profiles, while niraparib has an increased risk of cardiac events. In patients using other medications with known drug interactions, niraparib may be the preferred option for patients with ovarian cancer, and talazoparib may be the preferred option for patients with breast cancer because neither of these agents undergo hepatic metabolism. These agents also can incur large financial toxicities for patients, and olaparib currently has the broadest range of options for financial assistance.

Although these agents have similar approved indications, efficacy, and toxicity profiles, there are notable differences that may help direct choice of therapy and optimize treatment for patients. It is important to incorporate patient-specific factors to optimize PARP-inhibitor therapy for patients.