Merck's star oncology drug posts mixed results in a lung cancer trial

Merck's ($MRK) immuno-oncology treatment Keytruda met just one of its two goals in a late-stage lung cancer trial, a rare clinical hiccup as it works to keep pace with rival Bristol-Myers Squibb ($BMY) and fortify its position as more contenders move toward the market.

In a Phase II/III study involving more than 1,000 patients, Merck pitted two doses of Keytruda--the approved version, 2 mg for every patient kilogram, and an investigational dose 5 times larger--against the common chemotherapy docetaxel. Both levels of Keytruda posted a statistically significant improvement in overall survival, Merck said, but failed to reach that mark on the measure of progression-free survival for the whole population.

The mixed results come as Keytruda contends with Bristol-Myers' similar Opdivo on the lung cancer market. Both drugs are approved as second-line treatments for advanced non-small-cell lung cancer, but Keytruda's label is more restrictive, limiting it to patients with high expressions of the cancer-related PD-L1.

Merck has embarked on a slew of trials, including the one disclosed Monday, in an effort to widen the therapy's indication. Key to the latest results is that Keytruda benefited patients with lower levels of PD-L1 than it is currently approved to treat, ISI/Evercore analyst Mark Schoenebaum pointed out in a note to investors, clearing the way for Merck to expand Keytruda's potential patient population. The company plans to submit its latest data to the FDA by year's end and could widen Keytruda's label as soon as next year, Schoenebaum said.

Keytruda and Opdivo are part of a new class of therapies called checkpoint inhibitors, immuno-oncology treatments tabbed to bring in more than $30 billion a year at their peak. Behind Merck and Bristol-Myers, Roche ($RHHBY), AstraZeneca ($AZN) and the partnership of Merck KGaA and Pfizer ($PFE) are all at work on similar therapies bounding toward the market, and each contender is mounting scores of studies to demonstrate how its checkpoint therapy can work in a wide variety of cancers.

As it stands, analysts expect Opdivo to lead the pack with about $8.8 billion in sales by 2020, followed by Keytruda at $5.5 billion. But there are many trials, approvals and labels to be revealed in the intervening years that could change the landscape.

- read the statement

Read more on