AstraZeneca, Merck's Lynparza gets an edge over Clovis' Rubraca with prostate cancer survival win

AstraZeneca and Merck’s Lynparza has already shown it can stave off disease progression in certain genetically mutated prostate cancer patients. Turns out it can help them live longer, too.

In the phase 3 Profound trial, the PARP inhibitor topped Pfizer and Astellas' Xtandi and Johnson & Johnson's Zytiga at extending the lives of previously treated men with metastatic, castration-resistant prostate cancer and one of three genetic mutations.

RELATED: ESMO: AZ, Merck's Lynparza brings precision medicine to prostate cancer with 'game-changer' results

The win on that secondary endpoint follows a performance in which Lynparza bested those anti-androgen drugs at reducing the risk of disease progression or death—and doing so by a whopping 66%. Those results were presented at last year’s European Society for Medical Oncology (ESMO) annual meeting last September.

The new data also “should insure approval” of the drug in the population, Leerink Partners analyst Andrew Berens wrote in a note to clients. That FDA decision is due in the second quarter, thanks to Lynparza's priority review designation for that use.

“While approval was widely expected, this overall survival advantage was not anticipated, and we believe should prove to be a significant commercial advantage,” he wrote.

Lynparza will be wielding that advantage over competitor Clovis Oncology, which has its own FDA decision date in mCRPC patients with BRCA mutations slotted for May 15, Berens noted. Lynparza, meanwhile, posted its benefits in both BRCA-mutated patients and those with ATM mutations.

“Still pending is whether Lynparza gets a broad label that includes both BRCA-positive and ATM mutation mCRPC patients versus Clovis’ Rubraca, which is likely to be limited to BRCA-positive patients based on differences in the trials' inclusion criteria,” he wrote.

RELATED: AZ, Merck match Clovis with Lynparza 'priority' boost in prostate cancer

And the good news doesn’t end there for AstraZeneca and Merck, which are looking to build on their PARP lead by making Lynparza the only drug in its class with approvals in four different tumor types: ovarian cancer, breast cancer, pancreatic cancer and prostate cancer.

“We also believe that Lynparza’s strong randomized data versus standard of care Xtandi or Zytiga may better facilitate reimbursement and uptake versus Rubraca’s single-arm study, especially with an overall survival advantage,” Berens wrote.