In a monster showing, Merck's Keytruda combo slashes lung cancer death risk by half

Keytruda
Merck's Keytruda, combined with Alimta and chemo, cut first-line lung cancer patients' death risk by 51%. (Merck & Co.)

Merck & Co.’s Keytruda-chemo combo already has an FDA approval in first-line lung cancer based on phase 2 data, but some doctors harbored concerns about that trial’s smaller size, and investors worried the phase 3 results wouldn't measure up. They don't have to worry anymore.

The New Jersey pharma giant put up some stellar numbers Monday that should not only allay those concerns, but raise the bar for rivals looking to steal the class crown. At the American Association for Cancer Research annual meeting, Merck rolled out data showing that Keytruda, combined with Eli Lilly’s Alimta and platinum chemo, helped patients live significantly longer compared with chemo alone. In fact, the combo regimen cut the risk of death by 51%.

What’s more, the cocktail significantly extended patients' lives regardless of their PD-L1 levels. Patients with high levels of PD-L1, a biomarker Keytruda and its competitors target, saw their death risk slashed by 58%. In patients with low PD-L1 levels, that number registered at 45%. Patients whose tumors tested negative for the biomarker did almost as well on the regimen, with their risk of death slashed by 41%.

Free Daily Newsletter

Like this story? Subscribe to FiercePharma!

Biopharma is a fast-growing world where big ideas come along daily. Our subscribers rely on FiercePharma as their must-read source for the latest news, analysis and data on drugs and the companies that make them. Sign up today to get pharma news and updates delivered to your inbox and read on the go.

The findings—which Merck SVP Roy Baynes called “unprecedented in terms of the effect size"—are a big deal for the company. They apply to about 80% of the first-line non-small-cell lung cancer market, and that's a lot of patients. NSCLC is considered the holy grail of markets for immuno-oncology drugmakers because of its size. 

The study results also make it tougher for competitors, each pursuing their own first-line combo approaches, to top Merck’s performance. Roche is testing its own chemo combo, while Bristol-Myers Squibb and AstraZeneca are working on IO-IO duos, and they'll all have big numbers to beat. It will still take time for any of those rivals to come up with positive overall survival numbers in such a wide population—if they can do it at all.

RELATED: The top 15 best-selling cancer drugs in 2022

While archrival BMS did have its own positive first-line combo data to tout Monday, its numbers measured progression-free survival, or the amount of time until a patients’ disease worsens, rather than overall survival. Bristol doesn’t yet have OS numbers to show whether its Opdivo-Yervoy combo helped patients live longer.

“The gold standard here is overall survival. That’s obviously the goal of treatment,” Baynes said. “Progression-free survival is a proximal readout; oftentimes progression-free survival might portend improvement in overall survival, but that’s not necessarily the case.”

The new data should also boost uptake of the Keytruda-chemo combo. Some physicians had been concerned that Merck’s phase 2 study “was a fairly small study, and they were looking for confirmation,” Baynes said, adding that “certainly” the new trial, dubbed Keynote-189, “provides that confirmation very robustly.”