In its first major deal, Chimerix has granted Merck & Co. exclusive worldwide rights to its investigational oral nucleoside reverse transcriptase inhibitor (NRTI) CMX157, which has completed a Phase I trial in healthy volunteers. Chimerix will receive US$17.5 M upfront plus up to US$151 M in potential milestone payments and royalties. Merck has further expanded its HIV pipeline by licensing a preclinical-stage NRTI from the Japanese company Yamasa.