Data from: Implementation of Option B and a fixed-dose combination antiretroviral regimen for prevention of mother-to-child transmission of HIV in South Africa: a model of uptake and adherence to care

Introduction Initiating and retaining pregnant women on antiretroviral
therapy (ART) to prevent mother-to-child HIV transmission (PMTCT) remains
a major challenge facing African HIV programs, particularly during the
critical final months prior to delivery. In 2013, South Africa implemented
its “Option B” PMTCT regimen (three-drug ART throughout pregnancy and
breastfeeding, regardless of maternal CD4 count) and introduced once-daily
fixed-dose combinations and lifelong ART. Currently, the uptake of Option
B and its possible impact on adherence to PMTCT during the critical final
months of pregnancy is unclear. Materials and Methods  We
prospectively collected visit data from a cohort of adult, HIV-infected,
pregnant women between July 2013-August 2014 to estimate three models of
adherence to PMTCT during the final 16 weeks immediately preceding
delivery. Adherence was defined according to possession of antiretroviral
drugs, which was inferred from clinic visit records under varying
assumptions in each model. We describe uptake of the PMTCT regimen,
gestational age at initiation, and model possible scenarios of adherence
through delivery after the implementation of Option B. Results Among 138
women enrolled (median (IQR) age 28 years (24-32), median CD4 count 378
cells/mm3), median (IQR) gestational age at initiation was 22 weeks
(16-26). Estimates of adherence during the final 16 weeks of pregnancy
prior to delivery ranged from 75% (52-89%) under the best case scenario
assumptions to 52% (30-75%) under the worst case scenario assumptions.
Estimates of the proportion of women who would achieve 80% adherence to
PMTCT were <50% across all models. Conclusions Despite the switch
to Option B and once-daily dosing, South African women continue to
initiate PMTCT late in pregnancy, and estimations of regimen adherence, as
modelled using PMTCT visit attendance data, is poor, with <50% of
women reaching 80% adherence during final months of pregnancy across all
models. Further guideline changes and interventions are needed to achieve
vertical transmission goals. Trial Registration This study was nested
within the original RapIT randomized controlled trial which was registered
on ClinicalTrials.gov (Registration number) NCT01710397 on September 7,
2012 and the South African National Clinical Trials Register
DOH-27-0213-4177. The first participant in the RapIT study was enrolled on
May 8th, 2013.