Efavirenz versus nevirapine based first linetreatment in a South African cohort

Polly Clayden, HIV i-Base

A poster authored by Peter Block and colleagues compared the effectiveness of efavirenz and nevirapine in a multisite cohort of South African adults attending public health facilities.

This was a retrospective analysis of routine data from 27,350 adults initiated on ART between March 2004 and March 2007 in public health facilities. Participants were a median age of 34.4 (IQR 29.4-40.8) with a median CD4 count of 113 cells/mm3 (IQR 57-165).

The investigators found, over a median follow up of 9.3 months (IQR 4.6-17.7), in multivariate analysis, participants receiving efavirenz-based combinations were more likely to achieve undetectable viral load at six months, OR 1.31 (95% CI, 1.1-1.54) and at any time between six and 36 months, OR 1.28 (95% CI, 1.16-1.41). They were also more likely to die, AHR1.24 (95% CI, 1.07-1.45) and less likely to change regimen OR 0.53 (95% CI, 0.48-0.59).

Additionally, a subset analysis of 18,527 participants for whom pregnancy and TB status were known revealed no difference in mortality risk between those receiving efavirenz and nevirapine based regimens AHR 1.17 (95% CI, 0.99-1.37).


This study adds to a body of evidence showing superior results with EFV for first line ART when compared to NVP. Given the resource constraints in developing countries EFV should therefore be the preferred NNRTI for first line use. Protease inhibitors are not suitable for first line in developing countries due to increased cost. However; the possible link between EFV use in the first trimester and teratogenicity complicates its use with many women receiving EFV or initiating ART presenting only in the second trimester of pregnancy.

In the absence of suitable alternative NNRTIs or protease inhibitors, recommendations against the use of EFV in pregnancy need to be reviewed. In addition more work needs to be done to advocate for the reduction in price of suitable alternatives.


Bock P et al. Comparing the effectiveness of efavirenz and nevirapine for first-line antiretroviral treatment amongst an adult treatment cohort from South Africa. 10th International Congress on Drug Therapy in HIV Infection, 7–11 November 2010, Glasgow. Poster abstract P10. Published in Journal of the International AIDS Society 2010 13(Suppl 4). P10.

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