B/F/TAF to DTG/3TC Switch Study

Prior treatment

• Using any protocol-defined prohibited medicine where the participant is unwilling or unable to switch to an alternative (see Section 5.2. under Prohibited medications and non-drug therapies)
• Documented opportunistic infection within 4 weeks prior to the study enrolment

Other illness

• Confirmed treatment failure as defined by two consecutive HIV-1 RNA viral loads ≥ 50 copies/ml separated by at least 2 weeks, after at least 6 months on ART or after a documented HIV-1 RNA viral load \< 50 copies/ml
• Evidence of hepatitis B virus (HBV) infection based on the results of testing at screening for hepatitis B surface antigen (HBsAg), hepatitis B core antibody (anti-HBc), hepatitis B surface antibody (anti-HBs) and HBV DNA as follows:
  • Participants positive for HBsAg are excluded;
  • Participants negative for anti-HBs but positive for anti-HBc (negative HBsAg status), whether negative or positive for HBV DNA, are excluded;
  • Participants positive for anti-HBc (negative HBsAg status) and positive for anti-HBs (past and/or current evidence) are immune to HBV and are not excluded.
• Severe hepatic impairment (Class C) as determined by Child-Pugh classification
• Untreated syphilis infection (positive rapid plasma reagin \[RPR\] at Screening without clear documentation of treatment). Participants who are at least 7 days post completed treatment are eligible.
• History or presence of allergy or intolerance to the study treatment or their components or drugs of their class or a history of drug or other allergy that, in the opinion of the investigator or Medical Monitor, contraindicates their participation.
• Ongoing malignancy other than cutaneous Kaposi's sarcoma, basal cell carcinoma, or resected, non-invasive cutaneous squamous cell carcinoma, or cervical, anal or penile intraepithelial neoplasia.
• Participants who in the investigator's judgment, poses a significant suicidality risk. Participant's history of suicidal behavior and/or suicidal ideation should be considered when evaluating for suicide risk

Lab values

• Has AST and/or ALT at least 5-times greater than the upper limit of normal
• Has an estimated creatinine clearance (CrCl) below 30 ml/min (as estimated using the Cockcroft-Gault estimate for glomerular filtration rate)
• Any condition (including illicit drug use or alcohol abuse) or laboratory results which, in the investigator's opinion, interfere with assessments or completion of the study

Other

• Any evidence of any major 3TC resistance associated mutations (M184V/I and/or K65R and/or MDR) or presence of any major INSTI resistance associated mutation

• Able and willing to understand and comply with the protocol requirements, instructions and restrictions
• Able and willing to give informed consent
• Have been randomised to the B/F/TAF arm and completed the B/F/TAF-elderly study. Participants should be on B/F/TAF until day 1 of entry into the current study
• HIV-1 RNA viral load \< 50 copies/ml at screening (within 28 days prior to enrollment)