Muscle symptoms including myalgia, pain in extremity and rhabdomyolysis (0.31%, 4 cases) and CPK increase (0.15%, 2 cases) were fairly low in this survey, compared with other observational study (SCOLTA project) in patients receiving raltegravir, which were 5.2% and 21.1%, respectively [18]. This evidence concerns the gene PIK3C2A and rhabdomyolysis.