摘要 : During the 4 years to the end of 2007, the number of people in low-income and middle-income countries (LMICs) receiving antiretroviral therapy (ART) increased from 400 000 to 3 million. Although early mortality and retention in ca... 展开 During the 4 years to the end of 2007, the number of people in low-income and middle-income countries (LMICs) receiving antiretroviral therapy (ART) increased from 400 000 to 3 million. Although early mortality and retention in care remain significant challenges, the majority of reports from LMICs have shown encouraging immunological, virological and survival outcomes. Reported rates of switching to second-line ART regimens have been lower than expected, in part due to actual rates of treatment success, but mainly because of limited access to both virological monitoring and second-line drugs. Clinicians have also been reluctant to switch therapy due to regimen cost, complexity, inconvenience and lack of subsequent treatment options. As cohorts mature andexpand and access to virological monitoring and second-line regimens increase, however, rates of diagnosed treatment failure and switch to second-line regimens will increase. As the cost of second-line regimens are currently three to 20 times more expensive than mat of first-line regimens, these increases will challenge the cost-effectiveness and sustainability of HIV- treatment programmes. 收起