Effect of the CCR5 antagonist maraviroc on the occurrence of immune reconstitution inflammatory syndrome in HIV (CADIRIS): a double-blind, randomised, placebo-controlled trial

Background Immune reconstitution inflammatory syndrome (IRIS) is a common complication of antiretroviral therapy (ART) in patients with HIV. IRIS is associated with an increased risk of admission to hospital and death. We assessed whether CCR5 blockade with maraviroc reduces the risk of IRIS. Methods The CADIRIS study was a double-blind, randomised, placebo-controlled trial that recruited participants from five clinical sites in Mexico and one in South Africa and followed them for 1 year. Patients were eligible if they were adults with HIV, who were naive to ART, had CD4 count lower than 100 cells per mu L and HIV RNA greater than 1000 copies per mL. Participants were randomly assigned (1: 1) by permuted block randomisation to receive either maraviroc (600 mg twice daily) or placebo in addition to an ART regimen that included tenofovir, emtricitabine, and efavirenz for 48 weeks. Patients, care providers, and members of the research team were masked to treatment allocation. Clinical and laboratory evaluations were done at baseline, and weeks 2, 4, 8, 12, 16, 24, 48, and 60. The primary outcome was time to an IRIS event by 24 weeks. All patients who were randomly assigned contributed to the primary time-to-event analysis from the date of ART initiation until week 24, the time of an IRIS event or death. This trial is registered with ClinicalTrials.gov, number NCT00988780. Findings Between Dec 10, 2009, and Jan 17, 2012, we screened 362 patients; of whom 279 met the inclusion criteria and three refused to participate; thus 276 participants were randomly assigned (140 to receive maraviroc and 136 to receive placebo) .64 (23%) patients had IRIS events, 33 (24%) in the maraviroc group and 31 (23%) in the placebo group (p = 0.74). No difference in the time to IRIS events was noted between the treatment groups (HR 1.08, 95% CI 0.66-1.77; log-rank test p = 0.74). 37 participants (26%) in the maraviroc group had grade 3 or 4 adverse events compared with 24 (18%) in placebo group; p = 0.072); 25 (18%) in the maraviroc group and 21 (15%) in the placebo group had serious treatment emergent adverse events (p = 0.63). Interpretation Maraviroc had no significant effect on development of IRIS after ART initiation. Inclusion of this CCR5 inhibitor in an initial treatment regimen does not confer a meaningful protection from the occurrence of IRIS in people with advanced HIV infection.