BOSTON (AP) - Scientists fighting the ravages of AIDS in the Third
World have shown convincingly that a short and relatively
inexpensive combination of HIV drugs could reduce mother-to-baby
transmission rates in Africa far more effectively than the single
pill now used.
But the cost of the drug combinations could still be prohibitive
in some of the most impoverished parts of the world.
Scientists have long been searching for an alternative to the
AIDS drug now widely used in the developing world, nevirapine.
Nevarapine is cheap and highly effective at preventing babies
from contracting the AIDS virus from their mothers. But up to
two-thirds of women become resistant to the drug.
The drug combinations appear to have an extremely low rate of
resistance, and offer a relatively inexpensive and easy-to-take
alternative for many women.
"This is very promising for low-income countries," said one of
the researchers, Dr. Francois Dabis of Victor Segalen University
in Bordeaux, France.
However, the drug combination would likely cost more than double
the usual $8 for a single dose of nevirapine for mother and
newborn. As it is now, some countries can't afford nevirapine.
"It's important not to be rapidly overoptimistic," said Dr. Mary
Fowler, a U.S. Centers for Disease Control and Prevention
specialist in mother-to-baby HIV transmission. "The translation
from trials to programs is incredibly challenging."
The findings were presented in Boston on Thursday at the 12th
Annual Retrovirus Conference, the world's chief scientific
meeting on AIDS.
In impoverished lands, nevirapine is widely given in single doses
to infected pregnant women in labor and then to their newborns.
In the U.S., the complete three-drug HIV cocktail has cut
mother-to-baby transmission rates to around 2%. But patients in
the U.S. are given longer treatments, and drugs that are far more
effective and expensive than those tested in Africa.
The African studies - one in the Ivory Coast, one in Botswana -
reduced rates at four to six weeks after birth to about 5%, the
lowest ever recorded in Africa. Nevirapine in single doses
typically reduces that rate from around 35% to 12%.
In the Ivory Coast study, French and African-based researchers
used single-dose nevirapine in 329 women, but coupled it with two
other common AIDS drugs: AZT and 3TC, sold collectively as
Combivir. The Combivir was given to the mothers during pregnancy
and for three days after birth. The newborns were also given
single-dose nevirapine and AZT.
At 6 weeks of age, fewer than 5% of the newborns were infected.
Drug resistance was also extraordinarily low in the mothers. Only
1% became resistant to nevirapine, and just 8% to 3TC.
In the Botswana study of 1,179 births, mothers were given
multi-week AZT alone, and in combination with single-dose
The World Health Organization is expected to consider broadening
its guidelines soon in light of research on such new regimens.
Its recommendations now include single-dose nevirapine and an
"For a minimum additional cost, we may get many benefits," said
Dr. James McIntyre, an AIDS researcher in South Africa.
However, several researchers cautioned that single-dose
nevirapine will still be needed in many places.
"It is essential to preserve single-dose nevirapine as an option
when more complex regimens are unavailable," said Mark Isaac,
vice president of policy at the Elizabeth Glaser Pediatric AIDS
Foundation in Washington.
A separate arm of the Botswana study also gave a boost to
advocates of breast feeding for HIV-infected women. Some babies
were breast-fed and treated with AZT for six months, while others
were given formula. More of the first group contracted HIV , as
expected, since the virus can be passed through breast milk.
However, the two groups had almost identical rates of HIV-free
survival after 18 months.
Doctors have long known that the AIDS virus can be transmitted
through breast milk. But many are reluctant to discourage
breast-feeding in the Third World, since formula feeding has been
linked in the past to more baby illnesses and deaths from a
variety of causes.
About 40 million people worldwide are infected with HIV . About
65% live in sub-Saharan Africa. About 3 million people died in
the epidemic last year.