In the Sept. 13 issue of The Lancet, Johns
Hopkins and Ugandan researchers report final results of a
study showing that a safe, simple and inexpensive treatment
reduces transmission of HIV from mothers to babies during
childbirth and the first few weeks of life, offering a good
chance to curb the spread of HIV.
In their study of more than 600 women in Uganda,
giving one dose of nevirapine, a common HIV-fighting drug,
to HIV-positive mothers during labor, and one dose to their
newborns, reduced transmission by 41 percent, compared to a
multidose regimen of the drug zidovudine, commonly called
AZT. Africa is home to roughly 30 million HIV-positive
people, about 3 million of whom are pregnant women. The
report documents all the babies' health at 6 to 8 weeks and
at 18 months.
"This use of nevirapine, if widely implemented, has
the potential to prevent several hundred thousand new
infections every year," said J. Brooks Jackson, director of
pathology at the
Johns Hopkins School of Medicine. "This regimen is
extremely simple, safe and inexpensive, but access to HIV
testing and counseling remains a huge obstacle.
Fortunately, the recent availability of funds for HIV
prevention and treatment for Africa from the Bush AIDS
relief plan will likely make a huge difference in the
implementation of this nevirapine regimen."
Because of the drugs' short duration, some babies in
both treatment groups subsequently became infected with
HIV, most likely through breast feeding, but the nevirapine
group still had about 41 percent fewer HIV infections even
after a year and a half. In other attempts to reduce
mother-to-baby transmission of HIV, the initial gap in
infections has gotten smaller over time.
Worldwide, roughly 800,000 babies are infected with
HIV each year by mother-to-child transmission of the virus
during gestation or birth or by drinking breast milk,
according to UNAIDS and the World Health Organization. More
than 90 percent of these babies are in resource-poor
countries where treatment of HIV infection is not available
to mothers, alternatives to breast milk aren't widely
available, and strategies used elsewhere to prevent
mom-to-baby transmission are too expensive.
"In our study, single doses of nevirapine were more
effective than a short course of AZT in preventing HIV
transmission during birth and in the first weeks after
birth," said Jackson, who led the study with Francis Mmiro
of Makarere University in Kampala, Uganda.
Importantly, no serious adverse events were
definitively linked to either drug in the trial, into which
the last participants were enrolled in April 1999. Although
concerns regarding nevirapine's safety have been raised
over the last few years, this and other studies of the drug
at this dosage prove it is safe, the researchers said.
"We actually saw more rashes and other adverse events
in the AZT group than the nevirapine group, and even though
there were a few serious adverse events in both groups,
none could be conclusively tied to either study drug,"
When nevirapine is used for a long time in high doses,
and in combination with other antiretroviral drugs, serious
rashes and liver problems are the most common and dangerous
side effects. But Jackson emphasized that the onetime doses
used in the mother-to-baby prevention study are just a
fraction of those used in treatment.
Nevirapine's manufacturer, Boehringer-Ingelheim, has
offered the drug for free to less-developed countries for
use in efforts to prevent mother-to-child transmission, but
only through agreements with governments, not individual
hospitals or clinics.
In the study, 308 mothers and their babies received
AZT, and 311 pairs of mothers and infants received
nevirapine. Women in the AZT group received 600 milligrams
when labor began, and additional doses of 300 milligrams
every three hours until delivery. Babies in this group
received small, twice daily doses of AZT for a week. Women
in the nevirapine group received a single 200 milligram
dose of the drug at the beginning of labor, and babies
received a small dose within three days of birth.
At 6 to 8 weeks of age, 59 babies in the AZT group
were HIV positive, while only 36 babies in the nevirapine
group were HIV infected. By 18 months of age, 75 babies in
the AZT group and 47 in the nevirapine group were HIV
positive. Because infant mortality is quite high in
less-developed nations, the researchers also analyzed the
data using death or HIV infection as the endpoint, and the
gap between the nevirapine and AZT groups was still present
(63 babies in the nevirapine group and 92 babies in the AZT
group at 18 months had died or were HIV positive). Results
will be reported again once all babies reach age 5.
The study was funded by the National Institute of
Allergy and Infectious Diseases and funded by and conducted
through the HIV Prevention Trials Network, which is
principally funded by NIAID and is co-sponsored by the
National Institute of Child Health and Human Development,
the National Institute on Drug Abuse, the National
Institute of Mental Health and the National Institutes of
Health's Office of AIDS Research. Nevirapine was provided
by Boehringer-Ingelheim Pharmaceuticals.
Johns Hopkins authors on the paper are Jackson, Laura
Guay, Joseph Sherman, Constance Ducar and Corey