February 28, 202309:56 AM EST Merck’s Keytrudafails more...

February 28, 202309:56 AM EST

Merck’s Keytrudafails more prostate and lung cancer PhIII trials

https://endpts.com/mercks-keytruda-fails-more-prostate-and-lung-cancer-phiii-trials/

Merck’s cancer drug behemoth, the anti-PD1 Keytruda, has failed two more Phase III trials in the hard-to-treat prostate cancer setting and in a certain lung cancer, per a Tuesday update.

That marks more than half a dozen Phase III flops in the past 12 months for the drug, which won its first approval in 2014 and has generated dozens of billions in revenue for Merck, accounting for $20.9 billion in global sales last year.

The drug, when combined with Pfizer and Astellas’ Xtandi and androgen deprivation therapy, did not show improvement compared to placebo plus those two drugs on radiographic progression-free survival or overall survival at an interim analysis in certain prostate cancer patients. With that, Merck is discontinuing KEYNOTE-641, the drugmaker said Tuesday.

It marks at least the fourth late-stage failure for Keytruda in various prostate cancer trials since last March. The latest comes in patients with metastatic castration-resistant prostate cancer.

“Merck is informing study investigators of the decision and advises patients in the study to speak to their physician regarding treatment,” the Big Pharma said of the discontinued trial.

The other setback came in metastatic nonsquamous non-small cell lung cancer. Patients had certain EGFR mutations and had previously received a tyrosine kinase inhibitor, including AstraZeneca’s Tagrisso.

A combo of Keytruda, pemetrexed and chemo did not beat out a regimen sans Keytruda on either primary endpoint of survival or survival without progression of disease for patients with that type of NSCLC in the Phase III known as KEYNOTE-789.

Eliav Barr, Merck Research Laboratories CMO and SVP of global clinical development, did not mince words in a press release, saying the drugmaker has “asked the tough questions in an effort to fully explore the potential” of Keytruda in search of helping “as many patients as possible.”

“Science is rarely a straight line, and while we are disappointed in these study results, our research to investigate KEYTRUDA in many difficult-to-treat types of cancer continues in earnest,” he said, thanking investigators and patients in the two trials.

Keytruda has not met the bar on multiple prostate cancer studies in the past 12 months, as well as trials investigating its use in certain cancers of the liver, head and neck. Merck has touted late-stage successes in that time, including HER2-negative adenocarcinoma in November and biliary tract cancer last month.