Photo Credit: Merck

It looks like Merck & Co has just secured nearly all of the first-line non-small cell lung cancer market. 

On Wednesday the company announced that Keytruda had successfully nailed its primary endpoints in a study testing the drug among previously untreated patients with the squamous form of the disease, which represents about 25% to 30% of the overall market. 

When paired with chemo, the blockbuster held off cancer growth for longer and helped patients live longer writes Fierce Pharma. “The areas in which Keytruda has shown positive data” in lung cancer represent a potential market opportunity of $6.6 billion in the U.S. alone, said analyst Vamil Davin. 

The news will come as a shock for Roche and its PD-L1 checkpoint inhibitor Tecentriq, which in March managed to come up with positive results in an area of lung cancer its rivals hadn’t already reached. Merck now has a progression-free survival win to match Roche’s, but it has an overall survival victory, which is often regarded as a more important endpoint. 

“Barring any surprises,” Divan sees Merck “in a dominant position going forward.”