(Bloomberg) -- Roche Holding AG pointed to the success of a study by Merck & Co. as a sign that both companies are on the right track in pairing new immune-oncology drugs with an old standby of lung-cancer treatment: chemotherapy.

Roche’s own “aggressive approach” to experimenting with chemotherapy combinations was bolstered by Merck’s results in studying the impact of using its Keytruda medicine with the older treatment regimen, Dan Chen, the Swiss drugmaker’s global head of cancer immunotherapy, said in an interview on Monday. Merck’s combination was almost twice as successful at shrinking lung tumors in a mid-stage study than the standard treatment alone.

“We are not throwing spaghetti on a wall,” said Chen, speaking from the European Society for Medical Oncology’s annual meeting in Copenhagen. “We’re throwing darts, and with each dart trying to answer an important question.”

Both Merck and Roche are running larger final-stage studies, with results due starting next year, that could be used to seek approval to start selling a chemo-immunotherapy combination. One possibility is that chemotherapy combinations will be used mostly in patients shown to benefit less from stand-alone immune therapy, Sanford C. Bernstein & Co. analysts said in a note. Chemotherapy combinations will also probably cost health systems less than pairing two immune therapy drugs.

“If the data is comparable, also on durability, it’s going to be the cheaper option,” said Mirjam Heeb, who helps manage $186 million in health-care stocks, including Roche and Merck, at GAM Holding AG in Zurich. “Looking at the discussion we have around drug pricing, it is going to be competitive.”

Roche is also testing more than 20 combinations of immune therapies. The company reported successful stand-alone results from its Tecentriq medicine on Saturday in lung-cancer patients who had already tried at least one other drug unsuccessfully.

To contact the reporter on this story: Naomi Kresge in Berlin at To contact the editors responsible for this story: Chitra Somayaji at, Kristen Hallam

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