Twenty-four-month outcomes from a cluster-randomized controlled trial of extending antiretroviral therapy refills in ART adherence clubs.

INTRODUCTION: The antiretroviral therapy (ART) adherence club (AC) model has supported clinically stable HIV patients' retention with group ART refills and psychosocial support. Reducing visit frequency by increasing ART refills to six months could further benefit patients and unburden health systems. We conducted a pragmatic non-inferiority cluster randomized trial comparing standard of care (SoC) ACs and six-month refill intervention ACs in a primary care facility in Khayelitsha, South Africa. METHODS: Existing community-based and facility-based ACs were randomized to either SoC or intervention ACs. SoC ACs met five times annually, receiving two-month refills with a four-month refill over year-end. Blood was drawn at one AC visit with a clinical assessment at the next. Intervention ACs met twice annually receiving six-month refills, with an individual blood collection visit before the annual clinical assessment AC visit. The first study visits were in October and November 2017 and participants followed for 27 months. We report retention in care, viral load completion and viral suppression (<400 copies/mL) 24 months after enrolment and calculated intention-to-treat risk differences for the primary outcomes using generalized estimating equations specifying for clustering by AC. RESULTS: Of 2150 participants included in the trial, 977 were assigned to the intervention arm (40 ACs) and 1173 to the SoC (48 ACs). Patient characteristics at enrolment were similar across groups. Retention in care at 24 months was similarly high in both arms: 93.6% (1098/1173) in SoC and 92.6% (905/977) in the intervention arm, with a risk difference of -1.0% (95% CI: -3.2 to 1.3). The intervention arm had higher viral load completion (90.8% (999/1173) versus 85.1% (887/977)) and suppression (87.3% (969 /1173) versus 82.6% (853/977)) at 24 months, with a risk difference for completion of 5.5% (95% CI: 1.5 to 9.5) and suppression of 4.6% (95% CI: 0.2 to 9.0). CONCLUSIONS: Intervention AC patients receiving six-month ART refills showed non-inferior retention in care, viral load completion and viral load suppression to those in SoC ACs, adding to a growing literature showing good outcomes with extended ART dispensing intervals.