Codexis, Inc. has signed an agreement extension with Merck Sharp & Dohme Corp., to license and supply a proprietary enzyme used in the manufacturing process for sitagliptin, the active pharmaceutical ingredient in Merck’s JANUVIA and one of the active ingredients in Merck’s JANUMET.   Under a R&D agreement, Codexis and Merck used the CodeEvolver protein engineering platform technology to develop a customized enzyme to serve as a biocatalyst in the sitagliptin process. The resulting enz...