Comparison of adherence to generic multi-tablet regimens vs. brand multi-tablet and brand single-tablet regimens likely to incorporate generic antiretroviral drugs by breaking or not fixed-dose combinations in HIV-infected patients.

Adherence to antiretroviral (ARV) is crucial to achieve viral load suppression in HIV-infected patients. This study aimed to compare adherence to generic multi-tablet regimens (MTR) vs. brand MTR likely to incorporate ARV drugs without breaking fixed-dose combinations (FDC) and brand single-tablet regimens (STR) likely to incorporate generics by breaking the FDC. Patients aged of 18 years or over exposed to one of the generic or the brand of lamivudine (3TC), zidovudine/lamivudine (AZT/TC), nevirapine (NVP), or efavirenz (EFV), or the brand STR of efavirenz/emtricitabine/tenofovir (EFV/FTC/TDF). Adherence was measured by medication possession ratio (MPR) using both defined daily dose (DDD) and daily number of tablet recommended for adults (DNT). Adherence to generic MTR vs. brand MTR and brand STR was compared using Kruskal-Wallis. The overall median adherence was 0.97 (IQR 0.13) by DNT method and 0.97 (0.14) by DDD method. Adherence in patients exposed to generic MTR (n = 165) vs. brand MTR (n = 481) and brand STR (n = 470) was comparable by DNT and DDD methods. In conclusion, adherence to generic MTR was high and comparable with adherence to brand MTR and to STR. Utilization of DDD instead DNT to measure the MPR led to small but nonsignificant difference that has no clinical impact.