A study led by researchers at the Johns Hopkins
Bloomberg School of
Public Health found that
HIV-infected patients taking the antiretroviral drug
efavirenz were more likely to adhere to
treatment and less likely to experience virologic failure
and death compared to patients taking
Nevirapine is the most frequently prescribed drug for
patients undergoing highly active
antiretroviral therapy, known as HAART, for the treatment
of HIV/AIDS in sub-Saharan Africa,
where the study was conducted. The study is published in
the Oct. 18 issue of the journal AIDS.
"Our findings add to existing limited evidence that
efavirenz-based therapies produce a more
favorable virological and clinical outcome than
nevirapine," said Jean Nachega, lead author of the
study and associate scientist with the Bloomberg School's
Department of International
Health. "Patients started on nevirapine had an
increased risk of virologic failure and death [and] were
significantly less likely than those started on efavirenz
to achieve high treatment adherence."
Nachega, in collaboration with Gary Maartens,
professor of medicine at the University of Cape
Town in South Africa, and several other colleagues from the
University of Cape Town, examined the
records of 2,817 HIV-infected adults currently enrolled in
Aid for AIDS, a private-sector employer-
subsidized disease management program in Africa.
Participants were HAART-naive adults who began
nevirapine-based or efavirenz-based therapies between
January 1998 and September 2004.
Researchers determined how often patients requested
reimbursement for their purchases of
nevirapine- or efavirenz-based HAART to estimate adherence
to their treatment regimens. They also
evaluated patients' CD4 counts, viral load changes and
mortality, which are measurements of how well a
treatment is working. Program participants were in nine
countries in Africa, with the majority in South
Current World Health Organization guidelines recommend
the use of a non-nucleoside reverse
transcriptase inhibitor such as nevirapine or efavirenz in
resource-limited settings. Nearly 67 percent
of countries in sub-Saharan Africa recommend
nevirapine-based regimens for first-line therapy
because it is available at a lower cost and in a variety of
generic fixed-dose combination regimens. In
contrast, the U.S. Department of Health and Human Services
and the International AIDS Society-USA both recommend the
use of efavirenz because it has a more favorable toxicity
profile and greater efficacy.
"Given the rapid roll-out of antiretroviral programs
in Africa and the frequent use of first-line
nevirapine-based HAART in such programs, the assumption
that efavirenz and nevirapine are equally
effective needs to be reassessed," said Nachega, who is
also a professor and director of the Centre
for Infectious Diseases at Stellenbosch University in South
Africa. "Based on our results, there is a
critical need for a large randomized clinical trial to
definitively compare the outcomes of efavirenz
and nevirapine and for acceleration of efforts to develop
lower cost formulations of efavirenz,
including generic, fixed-dose combinations in Africa."
The study was written by Nachega, Michael Hislop,
David W. Dowdy, Joel E. Gallant, Richard E.
Chaisson, Leon Regensberg and Maartens.
The researchers were funded by grants from the
National Institute of Allergy and Infectious
Diseases of the National Institutes of Health and the NIH
Medical Scientist Training Program.