Efficacy and safety of switching from branded to generic antiretrovirals in virologically suppressed HIV-infected patients

Background

Aim of this study was to evaluate the efficacy and the safety of switching from branded to generic antiretrovirals in patients with HIV-RNA <50 copies/mL.

Methods

Matched-cohort study of patients followed at a single clinical center. Since September 2014, all patients with HIV-RNA <50 copies/mL who were receiving branded lamivudine or zidovudine/lamivudine or efavirenz were switched to the generic compound (switchers) and matched, in a ratio 1:1, for age (±5 years), gender, anti-HCV antibodies, nadir and (±50 cells/μL) baseline CD4+ count (±100 cells/μL), duration of antiretroviral therapy (±1 year), with patients with HIV-RNA <50 copies/mL, on treatment with unavailable generic compounds (non-switchers). Incidence rates (IR) of different outcomes were calculated and compared by Poisson regression model. A confirmed HIV-RNA ≥50 copies/mL defined virological failure; any change in the antiretroviral regimen was defined as treatment discontinuation.

Results

Four hundred forty patients were switched to generic compounds (268 [61%] on lamivudine, 65 [15%] on zidovudine/lamivudine, 87 [20%] on efavirenz and 20 [4%] on efavirenz and either lamivudine or zidovudine/lamivudine). Over a median follow-up of 15.0 (12.1–15.7) months, virological failure occurred in four switchers (IR: 0.07 [0.02–0.18]/100-person months of follow-up [PMFU]) and in ten non-switchers (IR: 0.20 [0.10–0.35]/100-PMFU) (p = 0.0003), while treatment discontinuation occurred in 118 switchers (IR: 2.05 [1.70–2.44]/100-PMFU) and in 128 non-switchers (IR: 2.37 [1.99–2.81]/100-PMFU) (p = 0.699).

Conclusions

After more than one year of follow-up, we found no evidence of increased risk of reduced efficacy or increased toxicity after switching from branded to generic lamivudine or zidovudine/lamivudine or efavirenz.

Low Incidence of HIV-1C Acquired Drug Resistance 10 Years after Roll-Out of Antiretroviral Therapy in Ethiopia: A Prospective Cohort Study

The emergence of HIV-1 drug resistance mutations has mainly been linked to the duration and composition of antiretroviral treatment (ART), as well as the level of adherence. This study reports the incidence and pattern of acquired antiretroviral drug resistance mutations and long-term outcomes of ART in a prospective cohort from Northwest Ethiopia. Two hundred and twenty HIV-1C infected treatment naïve patients were enrolled and 127 were followed-up for up to 38 months on ART. ART initiation and patients’ monitoring was based on the WHO clinical and immunological parameters. HIV viral RNA measurement and drug resistance genotyping were done at baseline (N = 160) and after a median time of 30 (IQR, 27–38) months on ART (N = 127). Viral suppression rate (HIV RNA levels ≤ 400 copies/ml) after a median time of 30 months on ART was found to be 88.2% (112/127), which is in the range for HIV drug resistance prevention suggested by WHO. Of those 15 patients with viral load >400 copies/ml, six harboured one or more drug resistant associated mutations in the reverse transcriptase (RT) region. Observed NRTIs resistance associated mutations were the lamivudine-induced mutation M184V (n = 4) and tenofovir associated mutation K65R (n = 1). The NNRTIs resistance associated mutations were K103N (n = 2), V106M, Y181S, Y188L, V90I, K101E and G190A (n = 1 each). Thymidine analogue mutations and major drug resistance mutations in the protease (PR) region were not detected. Most of the patients (13/15) with virologic failure and accumulated drug resistance mutations had not met the WHO clinical and/or immunological failure criteria and continued the failing regimen. The incidence and pattern of acquired antiretroviral drug resistance mutations is lower and less complex than previous reports from sub Saharan Africa countries. Nevertheless, the data suggest the need for virological monitoring and resistance testing for early detection of failure. Moreover, adherence reinforcement will contribute to improving overall treatment outcomes.

The Status of HIV-1 Resistance to Antiretroviral drugs in Sub-Saharan Africa

Access to highly active antiretroviral therapy (HAART) for persons infected with HIV in sub-Saharan Africa has greatly improved over the past few years. However, data on long-term clinical outcomes of Africans receiving HAART, patterns of HIV resistance to antiretroviral drugs and implications of HIV type-1 (HIV-1) subtype diversity in Africa for resistance, are limited. In resource-limited settings, concerns have been raised that deficiencies in health systems could create the conditions for accelerated development of resistance. Coordinated surveillance systems are being established to assess the emergence of resistance and the factors associated with resistance development, and to create the possibility for adjusting treatment guidelines as necessary. The purpose of this report is to review the literature on HIV-1 resistance to antiretroviral drugs in sub-Saharan Africa, in relation to the drug regimens used in Africa, HIV-1 subtype diversity and overall prevalence of resistance. The report focuses on resistance associated with treatment, prevention of mother-to-child transmission and transmitted resistance. It also outlines priorities for public health action and research.