Is Roche's latest Tecentriq win really a win for Merck's Keytruda?

With new lung cancer data, Roche touted another win Thursday for red-hot immuno-oncology drug Tecentriq. But the way some analysts see things, it may actually be a win for archrival Keytruda.

In a closely watched phase 3 study, Tecentriq—in tandem with chemo—cut down the risk of disease worsening or death for previously untreated patients with non-small-cell lung cancer compared with chemo alone. But at the interim check-in, the combo hadn’t hit statistical significance when it came to improving overall survival, which is widely considered to be a more important endpoint when it comes to cancer trials.

As Roche was quick to note, despite missing the significance mark, “a numerical improvement for the co-primary endpoint of overall survival was observed,” and “the study will continue as planned with final OS results expected next year.”

Right now, Roche is staying tight-lipped on the details, waiting for a medical meeting to do a full presentation. And until then, “ultimate commercial viability” is “hard to judge,” Credit Suisse’s EU pharma analysts wrote in a note to clients.

RELATED: Roche's Tecentriq grabs badly needed lung cancer win to keep Keytruda in its sights

But as the all-important first-line lung cancer market has begun to take shape over the last few years, analysts have tried their best to judge anyway, comparing trials of different drugs to look for clues as to which is most effective.

As Evercore ISI analyst Umer Raffat wrote to clients on Thursday, the latest Roche trial was “especially” relevant when it comes to pitting the Tecentriq-chemo pairing against market leader Merck’s Keytruda-chemo combo. The reason? “The backbone chemo used in this trial was comparable” to what Merck used in its own study. And with that in mind, Raffat thinks the latest results could be “another win for Merck.”

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“We don’t know the actual results of the trial, but if we compare the timelines of enrollment and readout vs KN-189, Merck seems to have clearly tracked ahead,” he wrote.

But with any imperfect comparison come caveats, one of them being that “it seems the control arm did better” in Roche’s trial, making the statistical significance benchmark harder to hit. Overall, though, “the competitor readouts have continued to solidify Merck’s leadership in 1L lung,” Raffat figures.

Of course, Roche’s cocktail could still come through on improving overall survival as the study progresses; just ask AstraZeneca, which has harped on that fact since its own first-line immuno-oncology trial failed to produce an early win.

But with Keytruda, which bears not one but two first-line approvals compared with its rivals’ zero, continuing to rack up market share unchallenged, “we believe it remains key that the Tecentriq/Alimta/chemo combination can show sufficient, clinically meaningful efficacy in PD-L1 low patients, or in different subpopulations in order for the combination to gain traction,” the Credit Suisse analysts wrote.