Emile Wamsteker | Bloomberg | Getty Images
Pedestrians walk across the street from a Merck & Co. facility in Summit, New Jersey
Incyte shares fell 20 percent in premarket trading Friday, while Merck shares were down about 2 percent.
The two companies would stop the study as it did not meet the primary goal of improving progression-free survival compared to patients on Keytruda monotherapy.
Merck’s Keytruda is approved for the treating several forms of cancer, including lung cancer and advanced melanoma. The companies said the study’s second main goal of overall survival was also not expected to reach a statistical significance.
The study was evaluating a combination of Incyte’s inhibitor Epacadostat and Merck’s Keytruda for the treatment of metastatic melanoma.