Months ahead of schedule, the US Food and Drug Administration approved Tesaro's small-molecule Zejula (niraparib) as a maintenance treatment for women with recurrent ovarian, fallopian tube or primary peritoneal cancer irrespective of their BRCA mutation or other biomarker status. The Waltham, Massachusetts–based biotech received a green light on March 27, far in advance of the Prescription Drug User Fee Act June 30 decision date, to treat women with ovarian cancer with partial or complete responses to previous platinum-based chemotherapy. Zejula is the third drug approved that inhibits the poly-ADP-ribose polymerase (PARP) enzyme, a DNA repair system that helps tumor cells repair damaged DNA strands; first was London-based AstraZeneca's Lynparza (olaparib) (Nat. Biotechnol. 33, 116, 2015) and second, Boulder, Colorado–based Clovis' Rubraca (rucaparib). But Tesaro's drug could command a larger market share because, unlike its rivals, Zejula benefits not only women who test positive for the germline BRCA mutation. In the phase 3 trial, the small-molecule drug delayed cancer progression by 12.9 months compared with 3.8 months in the control arm. At the time of going to press, Tesaro had not disclosed Zejula's price but the company predicts $1.9 billion a year in sales by 2022. The firm is also planning to conduct new trials with Zejula for metastatic ovarian, breast and lung cancers, including combination studies with Kenilworth, New Jersey–based Merck's anti-PD-1 antibodies Keytruda (pembrolizumab) and Basel-based Roche's anti-VEGF Avastin (bevacizumab). In March 2016, Tesaro entered a collaboration with Janssen Biotech, a Johnson & Johnson company, over commercialization rights to the drug in prostate cancer. New York–based Pfizer may be next in the approvals queue with tolazoparib, a PARP inhibitor it acquired with the purchase of San Francisco–based Medivation for $14 billion in 2016.