Effect of Addition of Raltegravir (MK-0518) to PI- or NNRTI-Based ART Regimens in HIV Infected Subjects With Undetectable Viral Load

Although ART has reduced the morbidity and mortality from HIV-1 infection, most individuals who stop ART experience rapid viral rebound. Effective ART can suppress viral load to less than 50 copies/ml; however, current treatment regimens cannot completely eliminate the infection. The primary purpose of this study was to assess the ability of the HIV-1 integrase inhibitor, raltegravir, to reduce viral load when added to ART regimens of HIV-1 infected patients who have achieved viral suppression to less than 50 copies/ml. The study lasted 24 weeks. Participants were randomly assigned to one of two arms. Participants in Arm A were administered raltegravir in addition to their usual ART regimen from study entry until Week 12. At Week 12, subjects halted raltegravir use and received a placebo until Week 24. Participants in Arm B were administered the placebo in addition to their usual ART regimen from study entry until Week 12. At Week 12, subjects halted the placebo and received raltegravir until Week 24. A real-time polymerase chain reaction (PCR) single copy assay (SCA) capable of detecting 1 copy of HIV RNA was used to assay viral load. The cross-over design allowed assessment of the effect of intensification with raltegravir between the two arms at Weeks 10/12 and every participant enrolled in the study receiving raltegravir for 12 weeks. Primary analysis focused on weeks 10/12 measurement and with no washout period, typical analysis of cross-over design was not intended. All participants had scheduled visits at Weeks 0, 2, 4, 10, 12, 14, 16, 22, and 24. A targeted physical exam occurred at all visits. Blood and urine collection occurred at selected visits. A medical/medication assessment occurred at trial entry. Drug dispensing and an adherence questionnaire occurred at some visits. A pregnancy test occurred at select visits. Participants' background ART medications were not provided by the study.