Background: Six (6) weeks (wks) neonatal antiretroviral therapy (ART), including QID ZDV (QZ), is an established part of regimens to prevent Perinatal HIV Transmission (PHT). Simplification could enhance adherence, reduce toxicity and costs, provided efficacy is not compromised. Here, a 4-wk regimen and switch to BID ZDV (BZ) is audited.

Methods: Data prospectively collected on HIV⁺ pregnancies include maternal/infant demographics, ART, delivery mode, infant CBCs, and outcome. Retrospective chart review retrieved missing data. Inclusion criteria: HIV⁺ infants who received postpartum (PP) ART. Frequency of hematologic toxicity, mean Hb and ANC of recipients of QZ and BZ were compared using Chi squared test and students t test.

Results: Between 11/94– 6/02, 229 infants of 225 pregnancies (4 twin) were delivered to 202 HIV⁺ women; 73% in the last 2 yrs of study. Sixty-seven percent (67%) of the women are African. Antenatal ART was given in 94% pregnancies; 67% triple therapy, 23% dual therapy, and 9% ZDV. Ninety percent (90%) of the women had intrapartum (IP) IV ZDV; 14 infants received only the PP component. 61% deliveries were SVD, 25% ELCS, and 14% EMCS. Of 229 infants, 41% received triple therapy (4 wks ZDV/3TC + NVP, 2mg/kg/dose, 1or 2 doses), 25% received 3TC/ZDV, and 31% ZDV. Prescribed duration of PP was 4 wks for 223 infants. Of ZDV recipients, 99 (43%) received 4 mg/kg/dose BID and 130 (57%) 2 mg/kg/dose QID. Ninety-seven percent (97%) of infants completed the prescribed regimen; 228/229 infants attended OPD (1LFU); 3 acquired HIV in-utero; and 225 infants are not infected. PHT rate was 1.3%–1.7%. The median number of CBCs in the first 12 wks was 4, 61% infants completed all evaluations. Overall, 33/228 (14%) had Grade 3 or 4 anaemia (15% BZ vs 14% QZ); 88/228 (38%) had Grade 3 or 4 neutropenia (30% BZ vs 40% QZ). All had resolved to ≤ grade 2 by wk 12. Mean Hb at D1, wks 2, 6, and 12 were 15.9, 12.8, 10.3, and 11.0 g/dl, respectively. Corresponding means for ANC were 7.63, 2.76, 2.22, and 1.84 x 10⁹/L. There were no differences in mean Hb or ANC values of recipients of BZ vs QZ dosing (p = 0.9); however, a trend toward less neutropenia in BZ recipients was observed.

Conclusions: Despite the limitations of a retrospective audit, this study suggests that efficacy will not be affected by shortening the 6-wk neonatal component. Concern that a switch to BZ dosing might be accompanied by greater hematologic toxicity was not proved.