Atazanavir and darunavir in pregnant women with HIV: Evaluation of laboratory and clinical outcomes from an observational national study

Background: Atazanavir and darunavir represent the main HIV PIs recommended in pregnancy, but comparativedata in pregnant women are limited.We assessed the safety and activity profile of these two drugs in pregnancyusing data from a national observational study.Methods: Women with atazanavir or darunavir exposure in pregnancy were evaluated for laboratory measuresand main pregnancy outcomes (e.g. preterm delivery, low birthweight, non-elective caesarean section and neonatalgestational age-adjusted birthweight Z-score).Results: Final analysis included 500 pregnancies with either atazanavir (n"409) or darunavir (n"91) exposure.No differences in pregnancy outcomes, weight gain in pregnancy, drug discontinuations, undetectable HIV-RNA,haemoglobin, ALT, total cholesterol, HDL cholesterol and LDL cholesterol were observed between the twogroups. At third trimester, exposure to darunavir was associated with higher levels of plasma triglycerides(median 235.5 versus 179 mg/dL; P"0.032) and a higher total cholesterol/HDL cholesterol ratio (median 4.03versus 3.27; P"0.028) and exposure to atazanavir was associated with higher levels of plasma bilirubin (1.54versus 0.32 mg/dL; P<0.001).Conclusions: In this observational study, the two main HIV PIs currently recommended by perinatal guidelinesshowed similar safety and activity in pregnancy, with no evidence of differences between the two drugs in termsof main pregnancy outcomes. Based on the minor differences observed in laboratory measures, prescribingphysicians might prefer either drug in some particular situations where the different impacts of treatment onlipid profile and bilirubin may have clinical relevance.