Three percent and 4 percent of elvitegravir and raltegravir patients, respectively, discontinued treatment due to adverse events. The frequency of serious adverse events was similar in both arms. The most common serious adverse events occurring in three or more patients in either group were pneumonia, cellulitis, suicidal ideation, dyspnea, bronchitis, chest pain and hepatitis.Laboratory abnormalities (Grade 3-4) occurring in greater than or equal to 5 percent of patients in either treatment arm were total bilirubin, AST, ALT, GGT, amylase, creatine kinase, total cholesterol and hematuria. The frequency of laboratory abnormalities was also similar in both treatment arms with the exception of Grade 3-4 liver abnormalities, which were higher among patients taking raltegravir (7 percent GGT; 5 percent ALT; 6 percent AST) as compared to elvitegravir (3 percent GGT; 2 percent ALT; 2 percent AST) with p-values less than or equal to 0.05 for all liver tests. Additional information about the study can be found at www.clinicaltrials.gov. About Elvitegravir Integrase inhibitors interfere with HIV replication by blocking the ability of the virus to integrate into the genetic material of human cells. Elvitegravir was licensed by Gilead from Japan Tobacco Inc. (JT) in March 2005. Under the terms of Gilead's agreement with JT, Gilead has exclusive rights to develop and commercialize elvitegravir in all countries of the world, excluding Japan, where JT retains rights. Elvitegravir is also a component of the Quad single tablet regimen. About Quad The Quad contains elvitegravir, cobicistat (a pharmacoenhancing or “boosting” agent that enables once-daily dosing of elvitegravir), and Truvada ® (emtricitabine and tenofovir disoproxil fumarate). In October 2011, Gilead submitted a New Drug Application to FDA for the Quad for the treatment of HIV. FDA has set a target action date for the Quad under the Prescription Drug User Fee Act (PDUFA) of August 27, 2012. Elvitegravir, cobicistat and the Quad are investigational products and have not yet been determined safe or efficacious in humans.