FDA Extends Review of Lynparza/Abiraterone for Prostate Cancer

The FDA has extended by three months the Prescription Drug User Fee Act (PDUFA) date for the pending supplemental new drug application (sNDA) for Lynparza (olaparib). The drug is being reviewed to treat adult patients with metastatic castration-resistant prostate cancer (mCRPC) in combination with abiraterone and prednisone or prednisolone. The agency indicated it needed additional time for full review.

Lynparza is a first-in-class PARP inhibitor developed by Merck and AstraZeneca. It is the first targeted treatment to potentially exploit DNA damage response pathway deficiencies, such as BRCA mutations.

In the United States, prostate cancer is the second most common cancer in men. About 10% to 20% of patients with advanced prostate cancer are estimated to develop castration resistant prostate cancer within five years. Patients with advanced prostate cancer have a poor prognosis, and the five-year survival rate remains low.

In November 2022, the European Medicines Agency’s Committee for Medicinal Products for Human Use recommended approval of Lynparza in combination with abiraterone and prednisone or prednisolone for adult patients with mCRPC.

Both the FDA and EU applications were based on the phase 3 PROpel trial presented at the 2022 American Society of Clinical Oncology Genitourinary Cancers Symposium and later published in NEJM Evidence. In this trial, Lynparza in combination with abiraterone and prednisone or prednisolone reduced the risk of disease progression or death by 34%. Median radiographic progression-free survival was 24.8 months for the Lynparza plus abiraterone arm versus 16.6 months for the placebo plus abiraterone arm.

The most common adverse events were anemia, fatigue and nausea. About 14% of patients who received the Lynparza combination discontinued treatment due to an adverse event

Lynparza is approved in the United States for patients with homologous recombination repair (HRR) gene-mutated mCRPC who have progressed following prior treatment with enzalutamide or abiraterone. Other indications include advanced ovarian cancer, HER2-negative early and metastatic breast cancer, and metastatic pancreatic cancer.

Earlier this year, Merck and AstraZeneca stopped a trial of Lynparza with or without Genentech’s Avastin (bevacizumab) for the treatment of patients with metastatic colorectal cancer. Lynparza as a monotherapy and in combination with Avastin did not meet its objectives at a planned interim analysis.