BACKGROUND: Over 11.7 million people are currently receiving antiretroviral therapy in low- and middle-income countries and focused efforts are needed to ensure high levels of adherence and to minimize treatment failure. Recently, international targets have emphasized the importance of long-term virological suppression as a key measure of programme performance. METHODS: We systematically reviewed publications and conference abstracts published between January 2006 and May 2013 which reported virological outcomes among HIV-1 infected adults receiving first-line antiretroviral therapy for up to 5 years in low- and middle-income countries. Summary estimates of virological suppression after 6, 12, 24, 36, 48 and 60 months of antiretroviral therapy were analysed using random-effects meta-analysis. Intention-to-treat analysis assumed all participants who were lost-to-follow-up, deceased or stopped antiretroviral therapy as had virological failure. RESULTS: Summary estimates of virological suppression remained >80% up to 60 months of antiretroviral therapy for all 184 included cohorts. Intention-to-treat analysis yielded 74.7% (95%CI: 72.2-77.2) suppression after 6 months and to 61.8% (95%CI: 44.0-79.7) suppression after 48 months on antiretroviral therapy. Switches to second-line antiretroviral therapy were reported scarcely. CONCLUSIONS: Among individuals retained on antiretroviral therapy, virological suppression rates during the first 5 years of antiretroviral therapy were high (>80%) and stable. Suppression rates in intention-to-treat analysis declined during 4 years