Anti-HIV Treatment Interruptions in HIV Infected Adults in South Africa

• To compare intermittent ART to continuous therapy by comparing endpoint CD4 counts between Groups 1 and 2 [ Time Frame: Throughout study ]
  
• Response to rabies vaccination and booster [ Time Frame: Weeks 16, 22, and 92 ]
  

• Comparison of treatment-associated toxicity and safety of 2 to 8 weeks of antiretroviral therapy (ART) interruption versus continuous ART [ Time Frame: Throughout study ]
  
• Determine the outcome of immune reconstitution by monitoring changes in T-cell subsets and the ability to maintain cell-mediated responses against various antigens [ Time Frame: Before and after intermittent strategy ]
  
• Viral evolution and genotypic changes that confer drug resistance [ Time Frame: During intermittent and continuous treatment ]
  
• Effect of treatment interruption on cardiovascular adverse experiences risk factors [ Time Frame: From Weeks 0 to 144 ]
  

Long-term toxicity and the high cost of medications are two problems faced by HIV infected people taking ART. Previous studies in HIV-infected patients suggest that ART with STIs may decrease drug exposure and lessen long-term drug toxicity, while not sacrificing viral suppression and patient health. This study will determine if ART with STIs can maintain the same level of immune function in HIV-infected people as continuous ART. This study will recruit patients in South Africa.

This study will last 3.5 years. At study entry, all participants will begin daily ART consisting of lamivudine, lopinavir/ritonavir, and stavudine. At Month 6, only participants who have responded well to ART (CD4 count greater than 450 cells/uL and viral load less than 50 copies/ml at Month 6) will be randomly assigned to one of two groups. Group 1 participants will participate in STIs during therapy, and Group 2 participants will receive continuous therapy. People in Group 1 will have treatment interruptions of 2, 4, and 8 weeks of duration in between 16-week periods of ART. Group 1 participants will re-initiate therapy if their CD4 count drops below 350 cells or evidence of clinical disease progression is present. Group 2 participants will continue taking ART throughout the study.

At screening, participants will undergo medical history assessment, a physical exam, and magnetic resonance imaging (MRI) and dual energy x-ray absorptiometry (DEXA) scans. There will be at least 22 study visits occurring approximately every 8 weeks, each lasting 45 to 60 minutes. At each study visit, participants will be required to bring any remaining pills with them so adherence can be assessed and will undergo medical assessments. Blood collection will occur at nearly all visits. For female participants, urine collection will occur at all visits. Participants will receive rabies vaccinations at Weeks 16, 17, and 22. A visit at Week 92 will include an MRI and participants will receive a rabies vaccine booster.