ASCO: Merck shows Roche up with big survival numbers in squamous lung cancer

CHICAGO—Over the last few years, nonsquamous non-small cell lung cancer data has grabbed most of the attention in immuno-oncology. Not this ASCO.

It’s the squamous form of lung cancer that's in the spotlight this time, and on Sunday morning at the American Society of Clinical Oncology annual meeting, Merck & Co. was the star of the show, upstaging Roche with better data.

Both Roche and Merck rolled out positive numbers for their PD-1/PD-L1 checkpoint inhibitors in previously untreated squamous patients, setting them up for a marketplace battle. But Merck one-upped its rival by showing a larger benefit, as well as overall survival data that Roche doesn’t yet have.

Saturday, the Swiss pharma giant got the party started, unveiling results from its IMpower131 study that showed its Tecentriq, when combined with chemotherapy, reduced the risk of worsening disease or death by 29% compared with chemo alone.

Sunday, though, Merck's Keytruda, combined with chemo, showed it could cut that same risk by 44% and pare down the risk of death by 36%, according to data from the drugmaker's Keynote-407 study. That's a performance Roy Baynes, Merck's SVP and head of global clinical development, called “truly remarkable.”

RELATED: Roche's Tecentriq triumphs in squamous lung cancer. Can it make its mark against Merck?

The numbers aren’t directly comparable, of course, because the studies were designed differently. “There were a lot of differences in the way these trials were run,” said Dan Chen, VP and global head of cancer immunotherapy development for Roche’s Genentech unit. And Baynes agreed that “there are all sorts of risks in doing cross-trial comparisons, not least of which” is that the patient populations weren’t exactly the same.

Still, pharma watchers will compare them, and some analysts expect Keytruda to leverage its data to prevail in the market showdown—especially given its positioning in first-line lung cancer on the whole. Right now, it’s the only member of its class to bear the FDA’s blessing for use in previously untreated patients, and it has not one, but two approvals.

RELATED: Merck rains on Roche's parade with double Keytruda win in squamous lung cancer

"Keytruda is already establishing a dominant position across various populations in 1st line lung cancer, so we assume doctors will heavily favor Keytruda in the squamous population as well," Credit Suisse analyst Vamil Divan wrote to clients Saturday, adding that the details from Roche's trial "matter, but now not so much."

Roche, for its part, still eagerly awaits its chance to share overall survival data for the Tecentriq-chemo team in squamous lung cancer. While that data aren't yet mature, “you can clearly see the start of that separation” in survival when the stats are charted, Chen said.

And in the meantime, he encouraged industry watchers to look at the body of evidence Tecentriq has so far produced across histologies and as part of different regimens.

“To date, all of these studies are positive,” he said. “I think that’s probably the better way to look at all of this.”