Cost-effectiveness of initial antiretroviral treatment administered as single vs. multiple tablet regimens with the same or different components.

OBJECTIVE To evaluate the efficiency of single-tablet regimens (STR) and multiple-tablet regimens (MTR) with exactly the same or different components. METHODS A study was conducted on HIV-1-infected antiretroviral-naïve patients from 6 Spanish or French centers, who were started on treatment with STR-Atripla®, or the same components separately (MTR-SC), or a different MTR (MTR-Other). Effectiveness was measured as percentage of HIV-RNA <50copies/mL at 48 weeks (ITT). Efficiency was the ratio between costs (direct cost of antiretrovirals plus outpatient visits, hospital admissions, and resistance tests) and effectiveness. RESULTS The study included a total of 2773 patients (759 STR-Atripla®, 483 MTR-SC, and 1531 MTR-Other). Median age was 37 years, 15% were HCV co-infected, 27% had a CD4+ count <200cells/μL, and 30% had viral load ≥100.000copies/mL. The duration of the assigned treatment was longer for STR-Atripla® (P<.0001). Response rates (adjusted for CD4+ count, viral load, and clustered on hospitals) at 48 weeks were 76%, 74%, and 62%, respectively (P<.0001). Virological failure was more common in MTR patients (P=.0025), and interruptions due to intolerance with MTR-Other (P<.0001). Cost per responder at 48 weeks (efficiency) was €12,406 with STR-Atripla®, €11,034 with MTR-SC (0.89 [0.82, 0.99] times lower), and €18,353 (1.48 [1.38, 1.61] times higher) with MTR-Other. CONCLUSIONS STR-Atripla® and MTR-SC regimens showed similar effectiveness, but virological failure rate was lower with STR-Atripla. MTR-SC, considered less convenient, had a marginally better efficiency, mainly due to lower direct costs. MTR-Other regimens had both a worse effectiveness and efficiency. Similar efficiency analyses adjusting for baseline characteristics should be recommended for new STRs.