Therapeutic Drug Monitoring to oPtimize ANtiretroviral regimeNs in HIV-infected Women Who wAnt to Breastfeed

This is a prospective, multi-center, longitudinal, mother-infant pair, therapeutic drug monitoring study. The aim of this study is to determine concentrations of antiretroviral drugs in plasma and breastmilk in people living with HIV who chose to breastfeed while using antiretrovirals. At a planned hospital visit an extra maternal blood sample (1 to 2 per visit) and extra infant blood sample (1 per visit) will be collected, as well as a breastmilk sample (1 to 2 per visit). Ideally, sample collection will take place at least during the 1, 3 and 6 month post partum follow up visit. Measured concentrations will be used to calculate milk to plasma ratios, relative and absolute infant dosages.

Inclusion criteriaPatients of at least 18 years of age at the moment of screeningPatients with HIV-1 as documented with positive HIV antibody test, HIV RNA of antigen testPatients breastfeeding their infantPatients using antiretrovirals for the treatment of HIV-1 with a marketing authorisation in Europe (table 1 in Appendix)Patients using current antiretrovirals for a minimum of 2 weeks to assure drug concentrations are in steady statePatients who are able and willing to sign an informed consentExclusion Criteria:No exclusion criteria will be used at the screening for the trial.