Keytruda dominates the cancer market. So one could imagine Merck just saying that if they keep Leron out of the market, they're good. But: one place where Merck needs us is Small cell lung cancer. Treg cells in lung cancer express CCR5... cancer with CTCs express CCR5.
Merck & Co. on Monday reported adding its cancer drug Keytruda to chemotherapy staved off disease progression longer than chemo alone in patients with small cell lung cancer. But the immunotherapy didn't appear to keep patients alive significantly longer.
Roche's competing drug Tecentriq received approval in March 2019 to treat a similar group of patients based on the results of a trial that demonstrated it significantly delayed progression and death. AstraZeneca's drug Imfinzi also has demonstrated that it improves overall survival.
Keytruda is the biggest seller in the PD-(L)1 class of drugs, with sales on track to hit $11 billion in 2019. Competitors are eager to steal some of that market share, and beating Keytruda in small cell lung cancer could help.