This randomised control trial, conducted in Chennai, India, compared structured interrupted therapy (SIT) and continuous therapy (CT) in relation to immunologic and virologic outcomes, adverse events (AEs) and cost of therapy. ART-naïve adult HIV1-infected participants with CD4 counts 50-350 cells/mm(3), and plasma viral load (PVL)>5000 copies/mL were enrolled and placed on Indian-manufactured generic ART: zidovudine(AZT)/stavudine(d4T)+lamivudine(3TC)+efavirenz(EFV). After at least six months of continuous therapy, subjects were randomised to SIT (one-week-on/one-week-off cycles) or CT. The primary end-point was the proportion of subjects maintaining CD4>200 cells/mm(3) at six and 12 months after randomisation. Secondary end-points were effective viral suppression (PVL<400 copies/mL), AEs and cost. All analyses used intention-to-treat methodology. Of 40 participants (69% male; mean age 36+/-7; median baseline CD4 and PVL: 162 cell/mm(3)and 259,000 copies/mL), 17 were randomised to SIT and 18 to CT. At randomisation, median CD4s for SIT and CT were 378 cells/mm(3) and 357 cells/mm(3), respectively. All participants had PVL<400 copies/mL at time of randomisation. Median CD4 six months after randomisation was 498 cells/mm(3) and 417 cells/mm(3) for SIT and CT respectively. All participants had CD4>200 cells/mm(3). One participant on CT and two on SIT had sustained PVL>400 copies/mL. There were no serious AEs or deaths. Structured interrupted therapy cost was half of CT. Structured interrupted therapy was effective at maintaining CD4 above 200 cells/mm(3). Adverse events were comparable in both groups, with 50% reduction in cost for SIT. Further research on such strategies may benefit resource-constrained settings.