UNIVERSAL 1: Pharmacokinetic Study of a Novel DTG/FTC/TAF Dose Ratio for Children

Inclusion Criteria:

• Age between 28 days and 10 years old

• Weighing 3 to <25 kg

• Confirmed HIV-1 infection (local, molecular methods)

• A parent or legal guardian is willing and able to give informed consent on behalf ofthe child as per national legislation and willing to adhere to the protocol

• Participant is willing to give informed assent if the trial site clinician deemsthem old enough and able to understand the age-appropriate information aboutparticipation in the study

• Girls who have reached menarche must have a negative pregnancy test at screening

• Subject is willing to start DTG/FTC/TAF regimen in the novel dose ratio for HIVtreatment

• Subjects already on a DTG-based ART regimen should be virologically suppressed atscreening

Exclusion Criteria:

• Age between 28 days and 10 years old

• Weighing 3 to <25 kg

• Confirmed HIV-1 infection (local, molecular methods)

• A parent or legal guardian is willing and able to give informed consent on behalf ofthe child as per national legislation and willing to adhere to the protocol

• Participant is willing to give informed assent if the trial site clinician deemsthem old enough and able to understand the age-appropriate information aboutparticipation in the study

• Girls who have reached menarche must have a negative pregnancy test at screening

• Subject is willing to start DTG/FTC/TAF regimen in the novel dose ratio for HIVtreatment

• Subjects already on a DTG-based ART regimen should be virologically suppressed atscreening

• History or presence of known allergy to DTG, FTC or TAF

• Alanine aminotransferase (ALT) ≥5 times the upper limit of normal (ULN), OR ALT ≥3xULN AND bilirubin ≥2xULN

• Patients with severe hepatic impairment or unstable liver disease (as defined by thepresence of ascites, encephalopathy, coagulopathy, hypoalbuminaemia, oesophageal orgastric varices, or persistent jaundice), known biliary abnormalities (with theexception of Gilbert's syndrome or asymptomatic gallstones)

• Current or anticipated need for TB therapy during the study

• Use of rifampicin-based therapy within 4 weeks before start trial

• Presence of comedication known to interact with trial medications

• Known resistance to INSTI or NRTI