Dolutegravir/Lamivudine in Treatment-Naïve Pregnant Women

Protocol Number: FH-94 Study Objetives: Primary: * To evaluate the virological response to Dolutegravir/Lamivudine in naive pregnant women with HIV who are starting antiretroviral therapy and vertical transmission in exposed neonates. Secondary: * To evaluate the incidence of maternal adverse events. * To evaluate perinatal outcomes at delivery. * To evaluate maximum virological suppression at delivery. * To evaluate the incidence of changes in body weight exceeding what is expected for gestation. * To evaluate the immune response based on changes in CD4, CD8, and CD4/CD8 ratio values during pregnancy. * Assess baseline resistance and the development of resistance to virological failure to integrase inhibitors and INTRs during treatment with DTG+3TC or DTG+TDF/XTC or DTG+TAF/FTC. * To evaluate the incidence of HIV infection in children that breastfeed. * To evaluate safety outcomes and virological response of DTG+3TC compared to DTG+TDF/XTC or DTG+TAF/FTC. Exploratory: * To explore the non-inferiority of DTG+3TC therapy compared to DTG+TDF/XTC or DTG+TAF/FTC treatment. * To evaluate the frequency of antiretroviral therapy withdrawal or modification before delivery.

Inclusion Criteria: All persons who are eligible must meet all of the following: 1. Confirmed HIV-1 infection: All tests must use blood, serum, or plasma samples. Documentation may be obtained from medical records. HIV-1 positive is defined as having HIV-1 RNA in plasma ≥ 1000 copies/mL, plus one antibody test or two positive HIV antibody tests (two different rapid tests or one rapid test and one positive ELISA/EIE test). If any of these diagnostic test results are not available, they will be performed at the SCR visit. In all cases, an HIV viral load test will be performed. 2. Not exposed to prior antiretroviral therapy (ART): No prior antiretroviral therapy, including exposure to PrEP and/or PEP in the last 6 months. 3. Ability to sign the informed consent form. 4. Plasma HIV-1 RNA ≥1000 copies/mL. Viral load from the last 30 days may be valid. . Age ≥ 16 years or older in Argentina, ≥ 15 years or older in Brazil. The participant must be of the age required in their country of residence to give legal informed consent. Otherwise, informed consent must be signed by a parent or legal guardian, according to country guidelines, in addition to the participant. 6\. Pregnant at any gestational age up to 32 weeks at the time of the screening visit: Viable pregnancy with a gestational age ≤32 weeks, defined according to menstrual history and/or ultrasound. Note: If the menstrual history is unknown or if there is a discrepancy between the menstrual history and the ultrasound, the gestational age will be determined based on the best technology available at each center. 7\. The participant intends to continue with the pregnancy. Exclusion Criteria: All eligible individuals must NOT meet any of the following criteria: 1. Documented resistance to 3TC (presence of the M184V/I mutation) or DTG (defined as the presence of G118R, Q148 H/K/R, or R263K). 2. Active hepatitis C infection. 3. Active hepatitis B (HBsAg positive or detectable HBV viral load in cases with isolated positive HBV anti-core). 3. Hemoglobin \=5 times the ULN, or ALT \>=3xULN and bilirubin \>=1.5xULN (with \>35% direct bilirubin). Participants with severe hepatic impairment (Class C) as determined by Child-Pugh classification 7. Presence of severe preeclampsia or other pregnancy-related events, in current or previous pregnancies, such as renal or hepatic abnormalities (grade 2 or higher proteinuria, elevated serum creatinine, CrCl \