Newly diagnosed lung cancer patients are half as likely to die of the disease if they take a Merck drug alongside standard chemotherapy, according to new trial data that eclipsed doctors’ expectations.

The trial, which compared a combination of chemo and Merck’s blockbuster Keytruda against chemo alone, found that patients in the combo group were 51 percent more likely to be alive after one year. Those getting Merck’s drug were also 48 percent less likely to have their cancer progress in the same period.