DTG/3TC Fixed Dose Formulations for the Maintenance of Virological Suppression in Children With HIV Infection Aged 2 to <15 Years Old

Inclusion Criteria for the Main trial: 1. HIV-1 infected children who are virologically suppressed for at least the last 6 months prior to enrolment 2. Aged 2 to \<15 years old 3. Weight 6 kg or higher 4. Children on the same triple-drug PI/r, NNRTI or INSTI containing ART regimen for at least 3 months 5. Girls who have reached menarche must have a negative pregnancy test at screening and randomisation 6. Girls who are sexually active must be willing to adhere to highly effective methods of contraception 7. A parent or legal guardian is willing and able to give informed consent on behalf of the child as per national legislation and willing to adhere to the protocol 8. Participant is willing to give informed assent if the trial site clinician deems them old enough and able to understand the age-appropriate information about participation in the study Inclusion Criteria for the Extended Follow up: 1. Participants remain on DTG/3TC at the end of the randomised phase, and in the opinion of the treating physician, derive ongoing benefit from DTG/3TC 2. Participants have no access to weight-appropriate DTG/3TC formulation via their national programme Exclusion Criteria for the Main trial : 1. Any previous switch in ART regimen for virological, immunological or clinical treatment failure 2. Any changes in ART in the last 6 months for reasons other than due to child's growth, drug stock-outs, changes in country guidelines and treatment simplification 3. Evidence of previous resistance to 3TC or INSTI 4. Any prior use of regimens consisting of single or dual NRTIs with the exception of a course of zidovudine for PMTCT 5. Known allergy or contraindications to dolutegravir or lamivudine 6. Diagnosis of tuberculosis and on anti-tuberculosis treatment; children can be enrolled after successful tuberculosis treatment 7. Treatment of co-morbidities with drugs which have significant interactions with antiretroviral treatment, requiring dose adjustment of the study drugs (children can be enrolled after the illness resolves) 8. Randomisation visit more than 12 weeks after the most recent screening visit 9. Evidence of hepatitis B infection with no protective immunity against hepatitis B: participants positive for HBsAg or HBcAb and negative for HBsAb 10. Anticipated need for hepatitis C virus therapy with interferon-based regimen prior to the primary endpoint. 11. Screening ALT equal to 3 or more times the upper limit of normal AND bilirubin equal to 2 or more times the upper limit of normal (ALT ≥3xULN AND bilirubin ≥2xULN) 12. Screening ALT equal to 5 or more times the upper limit of normal ALT (≥5xULN) 13. Patients with severe hepatic impairment or unstable liver disease (as defined by the presence of ascites, encephalopathy, coagulopathy, hypoalbuminaemia, oesophageal or gastric varices, or persistent jaundice), or known biliary abnormalities (with the exception of Gilbert's syndrome or asymptomatic gallstones) 14. Screening creatinine clearance \<50 mL/min/1.73m2 15. Patients aged ≥6 years at moderate or high risk of suicide as determined by Columbia-Suicide Severity Rating Scale (C-SSRS) 16. Girls who are pregnant or breastfeeding 17. Children who are in the legal custody of the State and do not have a parent or guardian able to provide informed consent on their behalf.