UPDATED: Merck's Keytruda posts 24% response rate in PhII bladder cancer study


COPENHAGEN, Denmark--Merck is chasing rivals Roche and Bristol-Myers Squibb in bladder cancer, but now, it has some new data in hand showing its checkpoint inhibitor, Keytruda, could combat the disease as an up-front treatment for some patients.

Data on the first 100 patients in the Phase II Keynote-052 study--which enrolled 374 previously untreated bladder-cancer sufferers ineligible for cisplatin chemo--showed that 24% responded to the therapy. The patients' tumors shrank, regardless of their PD-L1 biomarker status, Merck said Saturday at the ESMO 2016 Congress. And 6% showed complete responses, exhibiting no detectable cancer after treatment.

It’s a good sign for Merck, which is playing catch-up to rivals Roche and Bristol-Myers Squibb in the field. Roche’s Tecentriq made its debut in bladder cancer in May, bursting onto the immuno-oncology scene with an FDA approval in patients who’ve failed on platinum-based chemotherapy. And at this year’s ASCO meeting in June, Roche announced Phase II study data showing that 24% of cisplatin-ineligible bladder cancer patients saw their tumors shrink on Tecentriq.

Bristol, for its part, since picked up an FDA breakthrough designation, which could help its med Opdivo speed through the regulatory process to a bladder cancer thumbs-up.

But while the drugs can’t be directly compared without a head-to-head trial--“the populations studied all look different,” Roy Baynes, Merck SVP of global clinical development, told FiercePharma in an interview at ESMO--Baynes said Merck believes the new data represent “a very substantial advance for bladder cancer patients.”

Generally, front-line, cisplatin-ineligible patients “are poor performance status patients or have significant comorbidities that preclude the use of platinum-based chemo,” he said. “We’re talking about a pretty sick population.”

Of course, Merck isn’t keeping its development efforts confined to bladder cancer. It’s gearing up to battle its rivals in scores of different tumor types, looking for indications to add to the melanoma, non-small cell lung cancer and head-and-neck cancer nods it already has for Keytruda.

Sunday at ESMO, it took a big step toward doing just that in the front-line NSCLC setting, where the drug showed it could halve the risk of lung cancer progression and death in patients with PD-L1 expression of 50% or higher.

"Merck wants to make sure oncologists think of Keytruda first when thinking about cancer treatment," Bernstein analyst Tim Anderson wrote Sunday after a conference call with the company, adding, "Merck is actually running more studies with Keytruda than Bristol-Myers is running with Opdivo."

Related Articles:
Merck's Keytruda halves lung-cancer progression, death risk in big first-line victory
Merck's Keytruda fortunes look even better as doctors digest Opdivo's lung cancer failure
Bristol nabs Opdivo 'breakthrough' in bladder cancer--and gears up for Roche showdown
New Roche PD-L1 Tecentriq shines in study of untreated bladder cancer patients
Roche's Tecentriq bursts onto immuno-oncology scene, with Merck and BMS in its sights

Editor's note: This story was updated with analyst comments.