It’s been relatively smooth sailing for AstraZeneca and Merck’s Lynparza as it has gained indications in ovarian, breast, pancreatic and prostate cancer.
But on Thursday, the companies reported a snag as the FDA has delayed its target date for its decision on Lynparza in metastatic castration-resistant prostate cancer (mCRPC). The agency has pushed back the decision date to March to “provide further time for the full review of the submission,” Merck said.
The application is for Lynparza, a PARP inhibitor, to be used in combination with Johnson & Johnson’s androgen inhibitor Zytiga plus the steroid prednisone or prednisone alone for mCRPC patients.
A month ago, the European Medicines Agency’s Committee for Medicinal Products for Human Use recommended marketing authorization of the combination for mCRPC patients for whom chemotherapy is not clinically indicated.
The submission is based on results of the PROpel phase 3 trial which showed that the combination reduced the risk of disease progression by 34% versus standard of care (Zytiga plus prednisone). Including Lynparza also added more than eight months before disease progression or death.
Lynparza’s first endorsement in prostate cancer came in May of 2020 when the FDA sanctioned it for previously treated patients with mutations in their homologous recombination repair (HRR) genes. The drug won its first FDA approval in 2014 for ovarian cancer, followed by its nods in breast cancer (2018) and pancreatic cancer (2019).
Lynparza generated (PDF) sales of $2.75 billion for AZ in 2021, a 21% increase from the previous year. For its part, Merck reported $989 million in sales from the drug, a 36% increase year-over-year.
In prostate cancer, Lynparza already owns an edge over chief rival Zejula from GSK and Johnson & Johnson. J&J is working to gain an approval for Zejula in prostate cancer, but so far that drug is not cleared in this cancer.