At a session at the 19th International AIDS Conference (AIDS 2012) in Washington DC, UNICEF
official Chewe Luo called for transforming “PMTCT programmes into ART programmes”
in order to meet global HIV targets.
Luo expressed emphatic
support for an emerging model for prevention of mother-to-child transmission of
HIV (PMTCT): initiating lifelong antiretroviral therapy in HIV-positive pregnant
women, regardless of their CD4 count.
Since 2010, many
countries have based their national PMTCT policies on one of two interventions
identified in 2010 guidelines issued by the World Health Organization (WHO).
Under both Option A and Option B, HIV-positive pregnant women who have CD4 cell
counts of 350 or less are advised to start lifelong antiretroviral therapy using
a triple-combination regimen.
However, women
with higher CD4 cell counts are not considered medically eligible for lifelong antiretroviral
therapy, and are advised to take antiretrovirals only as prophylaxis against
mother-to-child transmission of HIV.
Options A and B
differ in their choice of antiretroviral regimens for mothers and infants.
Option A has a more complicated treatment protocol, with different maternal
regimens administered before birth, during delivery and during the postpartum
period. Option B simply calls for a triple antiretroviral regimen to be
administered from the fourteenth week of pregnancy until one week after
breastfeeding has ended (or until after childbirth if the woman is not
breastfeeding). Under both options, infants receive antiretroviral prophylaxis
as well.
In April 2012,
WHO released a 'programmatic update' to its 2010 guidelines. The update reported
that Option B has a number of benefits over option A. It went on to explain the
advantages of offering all HIV-positive
pregnant women the same triple-combination regimen – an approach dubbed “Option
B+”. The new option eliminates the use of a CD4 threshold to determine who is
eligible for lifelong treatment and who should only take antiretrovirals until
the infant is no longer at risk of HIV exposure.
On the basis of
the WHO update, UNICEF is now strongly encouraging countries to consider
switching to Option B+. In her remarks, Luo called attention to the experience
of Malawi, which adopted Option B+ in 2010. Malawi has
since seen major increases in the proportion of HIV-positive pregnant women
initiating antiretroviral therapy for the prevention of mother-to-child
transmission of HIV and for their own health.
Luo said that,
for the Malawian government, a major consideration in deciding to offer
antiretrovirals to all HIV-positive pregnant women was the impracticality of
providing universal CD4 screening to determine which women were eligible for
PMTCT regimens. Another factor was the growing evidence regarding the potential
for antiretroviral treatment to reduce HIV transmission to HIV-negative sexual
partners.
The Malawian
PMTCT programme uses the same triple-combination antiretroviral regimen that
serves as as the standard first-line antiretroviral regimen nationally. From a
programmatic standpoint, this makes drug procurement, distribution and
prescribing more straightforward.
The Malawian
government’s decision to invest in Option B+ is notable in light of its limited
resources for responding to a national adult HIV prevalence rate of 11%.
Cost has been a
factor encouraging many countries hard-hit by HIV to choose Option A over
Option B, since Option A costs less to implement. However, the operational
challenges associated with Option A may make it less cost-effective than Option
B in the long run, if Option A leads to a higher number of infants needing
treatment for HIV infection.
Option B+, not
surprisingly, is the most expensive option – but in a newly published Business Case for Options B and B+, the
Business Leadership Council for a Generation Born HIV-Free and UNICEF propose
that there may again be a net savings resulting from the higher outlay. An
important benefit of Option B+ is that it can be expected to lower HIV
transmission to male partners of HIV-positive women, since being on
antiretroviral therapy will make women less infectious. UNICEF also points out
that ongoing antiretroviral therapy should also reduce the risk of
mother-to-child transmission of HIV in subsequent pregnancies.
Ultimately,
cost-benefit analyses are not the only consideration for governments and the
international community. Shortly before the opening of the AIDS 2012
conference, UNICEF Executive Director Anthony Lake called attention to a “moral
argument” for Option B+ while speaking at a PMTCT leadership forum co-sponsored
by UNICEF and WHO.
“Option B+
treats women as more than vessels for having babies,” he said. “Of course every
woman wants her baby to live, but every woman wants to live, and who should
deny that right?”
UNICEF’s
decision to emphasise the benefits of Option B+ comes in the context of
evidence showing that progress must be accelerated in order for the global
community to achieve ambitious PMTCT-related targets.
At the 2011
United Nations High Level Meeting on AIDS, world leaders presented the
UNAIDS-crafted Global Plan Towards the
Elimination of New HIV Infections Among Children by 2015 and Keeping Their
Mothers Alive. The plan calls for a 90% reduction in the number of new HIV
infections among children and a 50% reduction in the number of AIDS-related
maternal deaths by 2015. The number of new HIV infections among children has
dropped in recent years, but modeling indicates that the rate of decline is not
steep enough to achieve the 2015 target.
PMTCT expert Prof. James McIntyre, speaking at the 4th International
Workshop on HIV Pediatrics shortly before the conference opened, expressed
concern about the speed of travel and the direction UNICEF is taking regarding
PMTCT options.
“It’s important in
this wave of optimism to stay grounded in science," he said, noting the
lack of long-term data on the outcomes of Option B+ implementation.
Finally, he noted, “Amidst all the hype, what happened to treating
all women with CD4 cell counts under 350? This seems to have been lost
in the
process.”
R.J. Simonds,
Vice President of Innovation and Policy at the Elizabeth Glaser Pediatric AIDS
Foundation, endorsed efforts to roll out Option B+, while at the same time
recognising that the implications of this strategy are not yet well understood.
“There is huge potential for an Option B+ approach, but we want to make sure
that we are doing this in a rational way,” he said in an interview.
“This is a substantive change,” Simonds added.
“We need to be moving quickly to generate evidence so that we can fine-tune
things.” He cited the need to learn more about adherence in women with higher
CD4 counts, and about retention in care.