AstraZeneca and Merck & Co. announced Wednesday that the FDA approved Lynparza (olaparib) for patients with homologous recombination repair (HRR) gene-mutated metastatic castration-resistant prostate cancer (mCRPC). Specifically, the PARP inhibitor is indicated for the treatment of adults with deleterious or suspected deleterious germline or somatic HRR gene-mutated mCRPC who have progressed following prior treatment with Astellas and Pfizer's Xtandi (enzalutamide) or Johnson & Johnson's Zytiga (abiraterone).
Approval was based on findings from the Phase III PROfound study, with results presented  at last year's European Society for Medical Oncology (ESMO) congress showing that Lynparza reduced the risk of disease progression or death by up to 66% and improved radiographic progression-free survival to a median of 7.4 months versus 3.6 months with Xtandi or Zytiga. AstraZeneca and Merck recently reported  additional results from PROfound showing that the PARP inhibitor also significantly improved overall survival compared to new hormonal agent treatments in men with mCRPC selected for BRCA1/2 or ATM gene mutations, a subpopulation of HRR gene mutations.
Dave Fredrickson, executive vice president of AstraZeneca's oncology business unit, said "today marks the first approval for Lynparza in prostate cancer," adding that results from the PROfound study "further establish that genomic testing for HRR mutations should be a critical step for the diagnosis and determination of treatment options for men with advanced prostate cancer."
Lynparza is currently under regulatory review in the EU and other markets as a treatment for men with HRR gene-mutated mCRPC. AstraZeneca and Merck are also conducting further studies of the drug in metastatic prostate cancer, including the ongoing Phase III PROpel trial as a first-line treatment in combination with Zytiga.
Earlier this month, the FDA approved  Lynparza in combination with Roche's Avastin (bevacizumab) for the maintenance treatment of certain adults with homologous recombination deficiency-positive advanced ovarian cancer. Meanwhile, in April, AstraZeneca reported  that sales of Lynparza, which is also authorised to treat certain patients with breast and pancreatic cancer, jumped 67% in the first quarter to $397 million.
For related analysis, see KOL Views: Handicapping the brewing 1L ovarian cancer tussle between Zejula and Lynparza .