Members of a large subset of prostate cancer patients with tumors that have already spread have a new chemotherapy-free treatment option. The FDA on Wednesday approved Lynparza, a PARP inhibitor from AstraZeneca (NASDAQ:AZN) and Merck (NYSE:MRK) that previously had been approved to treat people with ovarian and breast cancers.  

Not surprising 

The FDA completed its review of Lynparza for prostate cancer patients with tumors that test positive for homologous recombination repair (HRR) mutations a couple of months ahead of schedule. While the approval wasn't surprising, the FDA's decision came much more swiftly than expected.

Scientist looking at a colorful report.

Image source: Getty Images.

During the clinical trial that AstraZeneca and Merck ran to support Lynparza's label expansion, patients treated with Lynparza were 66% less likely to die or show signs of disease progression than those given Xtandi from Astellas Pharma and Pfizer (NYSE:PFE) or Zytiga from Johnson & Johnson (NYSE:JNJ).

Another blockbuster label expansion

Annual Lynarza sales climbed 85% higher in 2019 thanks to previous label expansions, and 2020 sales could surge in response to demand from a large underserved prostate cancer population. Prostate cancer's the second-most-commonly diagnosed malignancy among men in the U.S., and patients have up until now lacked treatment options if hormonal therapy stops working for them.  

The already-popular hormonal treatments will continue to play important roles in the treatment of prostate cancer, but patients need better options once these blockbuster drugs from Johnson and Johnson and Pfizer can't stop their disease from progressing. As a PARP-inhibitor that makes it hard for tumor cells to fix their own genetic material, rather than another hormone-based treatment, Lynparza could be in high demand in this indication. 

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