Use of antiretroviral therapy in resource-limited countries in 2006: distribution and uptake of first- and second-line regimens.

Objective: To address the information gap on current use of antiretroviral drugs (ARTs) in developing countries.

Methods: The AIDS Medicines and Diagnostics Service of the World Health Organization (WHO) carried out a multi-country survey in early 2006. Questionnaires covered the use of first- and second-line regimens in adults and children, and the rates of switching from first-line to second-line regimen. Weighted percentages of use of ARTs across the cohort of adults and children were calculated and correlated with 2006 WHO guidelines. A second analysis compared demand for ARTs with rates of production of active pharmaceutical ingredients.

Results: Twenty-three countries (96%) returned the questionnaires, representing 53% of relevant patients in developing countries as of June 2006, and comprising 92% adults and 8% children receiving ARTs. Response rates were highest for questions regarding first-line use and lowest for those regarding pediatric regimens. The distribution of first-line: second-line use was 96%: 4% among adults and 99%: 1% among children. For adults, 95% of those receiving first-line treatment, but only 25% of those receiving second-line treatment, were on regimens consistent with those preferred by the WHO. Among first-line users, the most common regimen (61%) was stavudine+lamivudine+nevirapine. Among second-line users, abacavir+didanosine+lopinavir/ritonavir was the most common regimen (24%). Among children, compliance with WHO guidelines was high among the respondents, with zidovudine+lamivudine+nevirapine reported as the main option. Estimates of first-year switching rate were highly variable, ranging from 1% to 15%, with only ten responses. Comparison of supply and demand showed that the stated production capacity for active pharmaceutical ingredients is sufficient to meet current demands for ARTs.

Conclusion: This survey has provided valuable information on the uptake of ARTs in developing countries and will help forecast future demand. Reporting for second-line and pediatric antiretroviral therapy should improve as national programs gain more experience. The current availability of active pharmaceutical ingredients appears to be sufficient to meet current demand. Further work is needed for an understanding of switching rates.