Joint Statement by the Centers for Disease Control and Prevention (CDC), the Joint United Nations Programme on HIV/AIDS (UNAIDS), The National Institutes of Health (NIH), and the Agence Nationale de Recherche Sur le SIDA (ANRS)

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A numnber of the trials that have been conducted, including this trial in Thailand, have
included a placebo arm. Use of a placebo arm was the only way in which it could be
Clearly and quickly established whether a shorter AZT regimen was safe and more
effective than no treatment at all, since previously these data were unavailable.
The results of the trial showed that this shortened regimen of AZT lowered the risk of
perinatal transmission by 51 % (from 18.6% without AZT to 9.2% With AZT). Although
this reduction is not equivalent to that observed 'in ACTG 076 - the longer regimen used
ifl developed countries -, this short-course regimen is more applicable and feasible for
many countries in the developing world and can have a significant impact on perinatal
transmission in these-,countries.
From the outset, this international research effort has been coordinated -by the UNAIDS
Informal Working Group on Prevention of Mother-to-Child Transmission of HIV, with
membership of all research institutions involved in mother-to-child transmission trials.
The working group has sought to identify the most promising drug regimens for testing
and to coordinate triall designs in order to allow optimal comparison of results and to
eliminate duplication of effort.
Next Sts
At the end of March, UNAIDS will host a meeting of international agencies and~e
interested governments from developed and developing countries in Geneva to find
ways of rapidly and effectively implementing the results of this and other trials iinto
public health policy as they become known.
It must be emphasized that the study in Thailand was conducted in a population of HI'!infected womnen who did not breastfeed. With the availability of an effective simplified
regimen applicable to many countries 'in the developing world, it is essential to now
evaluate the effectiveness of a very short AlT regimen in pregnant women who do not
present at prenatal clinics before the time of delivery and in women who breastfeed --
both of wh ich are common in many countries in the developing world. Because HIV can
also be transmitted through breast milk, it is possible that efficacy of the shortened
regimen may be lessened in countries where breastfeeding is the norm.
Further evaluation of the shortened regimen in such countries 'is therefore essential, as
well as exploration of the relevance of early weaning or other strategies. It will also be
imprtnttoevlutereimnstht reevn imL.thAltheCDCsort-curseAZfTy

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