Adverse events (AEs) reported in Study 1 and Study 2†.

†There were no AEs reported in the fasted period of Part B of Study 1 or Part A of Study 2. (1) One subject administered 600 mg QD GSK263 developed severe myalgia approximately 9 days after starting dosing that lasted several days after stopping GSK263. The AE was considered by the investigator to be related to the study drug. The myalgia was not accompanied by changes in creatine kinase, aspartate aminotransferase, or viral titers, and the systemic exposure of GSK263 in this subject was comparable to exposures observed in other subjects administered 600 mg QD. No alternative etiological factor for the myalgia was identified in this subject. It is noteworthy that no muscle toxicity had been observed in the routine rodent and dog toxicity studies conducted with GSK263. (2) Seven subjects were withdrawn in Study 1 due to AEs, but none of these were attributed to GSK263 by the investigator.Abbreviations: AE, Adverse Event.