The Current Landscape of PARP Inhibitors in Ovarian Cancer

Abstract

The aim of this study is to discuss the background of PARP inhibitors and to provide an overview of the utility of these drugs for treatment of epithelial ovarian cancer. Numerous phase I–III trials are presented within the manuscript that outline the safety and efficacy of several PARP inhibitors in women with primary and recurrent ovarian cancer. There are now three FDA-approved PARP inhibitors for use in ovarian cancer patients in the USA: olaparib, niraparib, and rucaparib. These drugs have activity both alone and in combination with other agents, including chemotherapy and targeted anti-cancer drugs. Although PARP inhibitor toxicities often overlap with chemotherapy including myelosuppression, fatigue, and gastrointestinal distress, there are idiosyncratic differences in adverse event profiles and peculiar aspects of each drug. Additionally, the indications for use differ with respect to line of chemotherapy, whether a germline or somatic BRCA mutation is required, and maintenance versus active treatment intention. Although these were initially thought to be only applicable to patients with germline BRCA mutations, we now know that other patients benefit from these agents alone and in combination. The first PARP inhibitor was approved for use in the USA less than 3 years ago, but we are rapidly gaining knowledge about when and in which settings to use these drugs. Continued focused study with clinical trials will enable us to identify the optimal patient populations for prescription of these agents.