In such cases, FDA strongly recommends monitoring for increases in serum osmolality, serum creatinine and other signs of toxicity. 900 mg/m2 once daily Mon/Wed/Fri <6 months: 120 mg once daily Mon/Wed/Fri 6–12 months: 240 mg once daily Mon/Wed/Fri 8.1.1 Zidovudine monotherapy is recommended if maternal VL is <50 HIV RNA copies/mL at 36 weeks' gestation or thereafter before delivery (or mother delivered by PLCS while on zidovudine monotherapy). Grading: 1C For women with fully suppressed this website HIV and a history of zidovudine resistance see discussion below. Zidovudine monotherapy for the infant has been part of the PMTCT strategy since publication of the ACTG 076 results [61]. The relative
contributions of the antenatal, peripartum and infant components have been difficult to quantify. In ACTG 076 neonatal zidovudine 2 mg/kg every 4 h (five doses) was given for 6 weeks. Monotherapy for the infant is appropriate when there is a very low risk of HIV transmission. This occurs when a mother on combination therapy delivers with a VL <50 HIV RNA copies/mL. The neonate should receive single-drug therapy for 4 weeks; this is practically
easier for the family and reduces the risk of adverse events. With many years of experience, twice-daily zidovudine monotherapy is the neonatal treatment of choice, whatever the maternal ART combination. For infants born to mothers on fully suppressive ART, zidovudine monotherapy PEP remains reasonable even where the mother has a previous history of zidovudine exposure with resistance (thymidine-associated mutations). selleck chemicals llc On HAART, the risk of transmission in the mother with fully suppressed viral replication is extremely low ( about 0.1%), and although history of zidovudine resistance in maternal virus and infant PEP regimen has not been dissected, the frequency of transmission of zidovudine-resistant virus is concomitantly very low. Data from the era when only maternal
zidovudine monotherapy was available indicate preferential transmission of wild-type over zidovudine-resistant virus PAK5 when a mixed population of virions are present [248]. In the Swiss cohort, none of six infants born to mothers harbouring zidovudine-resistant HIV (based on codon 215 analysis only) became infected [249]. In a subset of participants of the ACTG 076 study, the prevalence of low-level zidovudine resistance was 4.3% (mutation at codon 70) and no significant increase in the risk of transmission was observed after adjusting for VL at delivery (OR 4.8; with wide 95% CI 0.2–131; P = 0.35) [250]. High-level resistance was not reported and the median CD4 cell count in the women was 540 cells/μL. In retrospective cohort studies from France [251] and the USA [252], 20% and 8.3%, respectively, of HIV-positive newborns had zidovudine-resistance mutations after maternal zidovudine prophylaxis.