The Common Factor, no. 8

June 1994

The Common Factor

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June 1994 The Common Factor.11.......... 11:1 IilliI Ill!! I A j 1
ME= Mal It IN'

Study Concludes that AZT Reduces HIV
Transmission from Mothers to Infants
by Gregory J. Haas

A CLINICAL TRIAL which has been
controversial from its onset was
stopped in February when an interim
analysis of the data concluded that
the use of AZT in HIV-infected
pregnant women significantly
reduces the risk of the baby
becoming infected with the virus.
While this is a major result, it will
continue to be controversial.
The clinical trial, known as
ACTG 076, administered either AZT
or a placebo to HIV-positive pregnant women beginning in the 2nd
or 3rd trimester and continuing
through the rest of their pregnancy
and labor. The AZT or placebo was
then given to the infants for the first
six weeks of life. The women had
more than 200 CD4 cells (most had
more than 500) and had not taken
AZT before. A majority were African-American or Latina.
The data released to the press
included 364 infants, 180 who had
received AZT and 184 who had re
ceived placebo. Of the 180 babies
on the AZT regimen, 14 (or 8.3%)
were determined to be HIV-positive.
Of the 184 babies on placebo, 40
(25.5%) were HIV-positive. Statistically, this is a very significant difference and led the ACTG (AIDS
Clinical Trials Group) to stop enrolling women into the study.
(The study found that side effects
in the infants due to AZT were rare
and mild. The most common being
anemia which quickly resolved. The

toxicities in the women in the two
arms were also comparable.)
The overall rate of transmission
was only 14.6%, which is lower than
previous U.S. estimates. This is good
news to HIV-positive women who
would like to have children.
Unresolved Questions
1) Because infants carry their
mothers' antibodies for a time after
birth, their "true" HIV status cannot
be determined for many months.
The original design of the study was
to evaluate the HIV status of the infants at age 18 months. Of the 364
babies included in the analysis only
75 actually completed the full 18
month study. In fact, only 233 had
information about HIV status at 6
months. Will the striking results of
this study be confirmed when all the
data is in?
2) What are the long term effects of giving AZT to a fetus? Side
effects of some drugs taken by a
pregnant woman may not be recognized in the child for years. In
this study, hundreds of HIV-negative babies received AZT in utero
and as infants. It is essential that
very long-term follow-up be done
on the women and children, both
HIV-positive and HIV-negative.
3) The transmission rate was
reduced by AZT, but the death rate
(See Vertical Transmission, page 29)
the pneumocystis.
The previously approved treatments for PCP are TMP-SMX (Bactrim), pentamidine, and atovaquone
(Mepron). Dapsone is also often used.
Vaccine Trial Canceled
The controversial therapeutic
vaccine study that was to be run by
the Defense Department has been
canceled. In late 1992 Congress appropriated $20 million to study the
gpl6O vaccine developed by MicroGeneSys. Because of serious doubts
about the benefits of the vaccine, the
NIH, FDA and HHS decided to re
turn the money to the Army's AIDS
research budget.

INN I

Updates
Beta Carotene and HIV
A double-blind, placebo-controlled clinical trial of beta carotene
recently found significant increases
in CD4% and CD4/CD8 ratios in the
persons taking beta carotene.
Twenty-one HIV-positive participants were split into two groups
who either received 180 mg of beta
carotene a day or a placebo. Upon
entry the participants had CD4
counts between 100 and 600 and 16
of the 21 were taking AZT, ddl and/
or ddC. The only side effect seen
was a slight orange tint in the skin
of the beta carotene users.
Researchers speculated that the
positive results were due to beta

carotene's activity as an antioxidant
in preventing free radical damage to
cells. The study was conducted by
Oregon Health Sciences University.
New PCP Treatment
In December the FDA announced its approval of the fourth
treatment for pneumocystis carinii
pneumonia (PCP). Trimetrexate
glucoranate (brand name NeuTrexin)
is now available for use in cases of
symptomatic PCP.
Trimetrexate is administered intravenously and must be accompanied by another drug, Leukovorin,
which protects the healthy cells in
the lungs while trimetrexate attacks

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