In the December 2016 issue, the piece “Drugs that made headlines in 2016” (Nat. Med. 22, 1377–1379, 2016) incorrectly stated that the FDA was further reviewing the drug Keytruda for a common form of lung cancer under priority review. The approval that had been given to the drug in October was the result of a priority review. The error has been corrected in the HTML and PDF versions of this article.