Objectives: Compare HIV injecting and sex risk in patients being treated with methadone (MET) or buprenorphine-naloxone (BUP).
Methods: Secondary analysis from a study of liver enzyme changes in patients randomized to MET or BUP who completed 24 weeks of treatment and had 4 or more blood draws. The initial 1:1 randomization was changed to 2:1 (BUP:MET) after 18 months due to higher dropout in BUP. The Risk Behavior Survey measured HIV risk before 30 days at baseline and weeks 12 and 24.
Results: Among 529 patients randomized to MET, 391 (74%) were completers; among 740 randomized to BUP, 340 (46%) were completers; 700 completed the Risk Behavior Survey. There were significant reductions in injecting risk (P < 0.0008) with no differences between groups in mean number of times reported injecting heroin, speedball, other opiates, and number of injections; or percent who shared needles; did not clean shared needles with bleach; shared cookers; or engaged in front/back loading of syringes. The percent having multiple sex partners decreased equally in both groups (P < 0.03). For males on BUP, the sex risk composite increased; for males on MET, the sex risk decreased resulting in significant group differences over time (P < 0.03). For females, there was a significant reduction in sex risk (P < 0.02) with no group differences.
Conclusions: Among MET and BUP patients who remained in treatment, HIV injecting risk was equally and markedly reduced; however, MET retained more patients. Sex risk was equally and significantly reduced among females in both treatment conditions, but it increased for males on BUP and decreased for males on MET.
Trial registration: ClinicalTrials.gov NCT00315341.