Merck announced Tuesday that the FDA has accepted its submission for a combination drug of its immuno-oncology agent Keytruda and chemotherapy for the treatment of advanced lung cancer and granted it Priority Review. Merck will receive a decision from the FDA on or before May 10.
If it receives that approval, the Keytruda combination drug would likely come to market before Bristol-Myers Squibb’s, Roche’s, and AstraZeneca’s immuno-oncology combinations. It could also significantly expand the reach of Keytruda to more lung cancer patients as a standalone therapy, according to analysts.
Some drugmakers see the strategy of pairing immuno-oncology agents with existing treatments, like chemotherapy, as the future of cancer treatment. There are two prevailing rationales: Either that two therapies combined should have higher efficacy than either one on its own, or that low doses of two drugs may have a lower overall toxicity than a full dose of one drug.
Positive results for the Keytruda combination were first reported at the European Society of Medical Oncology conference in 2016 as part of a Phase-II readout. Merck didn’t point out that it planned to file the drug with regulators based on that Phase-II data at the time, leaving analysts surprised by Tuesday’s news that FDA had accepted the data.
That Phase-II trial, Keynote 021, studied Keytruda and chemotherapy in a broader patient population than Keytruda had been studied as a standalone treatment. The trial evaluated the combination in patients regardless of their PD-L1 expression; Keytruda’s standalone or monotherapy trial had only studied its efficacy in patients with high levels of the biomarker’s expression.
As a result, Credit Suisse analyst Vamil Divan wrote in an investor note Wednesday that this approval could open the door for an expansion in first-line use for Keytruda, potentially broadening its applications to all patients who do not have an EGFR or ALK mutation, two other important biomarkers in non-small cell lung cancer.
Evercore ISI analyst John Scotti said the approval could greatly expand Keytruda’s market to nearly all patients in first-line non-small cell lung cancer, from the 25-30% that it is available under its current label — an opportunity worth up to $14 billion. Scotti also wrote that an approval in May would give Merck “a significant first-mover advantage.”
Divan agreed, noting that the potential label expansion would meaningfully increase Keytruda’s market opportunity in non-small cell lung cancer as well as drive more acceptance among payers. The approval could signal to oncologists that Keytruda is a “foundational” therapy in the category, he argued, especially since Phase-III data from Bristol-Myers Squibb’s, AstraZeneca’s, and Roche’s combination drugs aren’t likely to be reported before the end of 2017.