Merck's Keytruda, Roche's Tecentriq may lag chemo in some cancer patients, FDA says

Roche's Tecentriq and Merck's Keytruda have been associated with decreased survival in some patients with low levels of PD-L1, the biomarker those two drugs are designed to target. (Roche)

Merck and Roche’s immunotherapies are each approved solo for certain previously untreated bladder cancer patients. But for other frontline patients, the drugs may be hurting their survival chances.

The FDA warned doctors, trial investigators and the public on Friday that Merck's Keytruda and Roche's Tecentriq turned up red flags in recent trials. Early reviews from oversight committees found that in each of two studies—one testing Keytruda and the other testing Tecentriq—patients with low levels of the PD-L1 biomarker treated with the immunotherapies saw their survival chances decrease compared with those who took platinum chemotherapy.

Both Keytruda and Tecentriq are conditionally approved to treat certain bladder cancer patients who've not been treated before.  They're cleared for patients with cancer that has spread locally or throughout the body—regardless of their PD-L1 status—if they're not eligible for cisplatin chemotherapy regimens.

That's not the population in the trials the FDA's flagging. Patients in those studies were eligible for platinum-based chemo, the agency was quick to point out.

Still, regulators are asking doctors and patients to make sure they report any side effects related to either drug, and they’re recommending physicians stick to the products’ labels when it comes to prescribing.

While players in the PD-1/PD-L1 class—Keytruda in particular—seem to be racking up new approvals left and right, It’s not the first time either drug has run into problems in trials. Tecentriq, for one, ran the risk of losing its bladder cancer approval last year after flopping the study that was meant to cement its accelerated approval in second-line bladder cancer.

Keytruda, on the other hand, doesn’t have any previous bad marks in bladder cancer but has triggered safety warnings in trials for other cancer types. Last September, in the wake of trial deaths, the FDA issued a statement highlighting the risks of pairing Keytruda with dexamethasone and either Celgene’s Revlimid or Pomalyst as treatment for multiple myeloma.