The Antiretroviral Speed Access Program Switch (ASAP-Switch) Study

Inclusion Criteria: * Willing and able to understand the requirements of study participation and provide signed and dated written informed consent prior to performing study procedures; * 18 years of age or older; * Living with HIV (type 1) (as confirmed by a fourth generation HIV Ag/Ab combination assay); * Patients at their first visits ever at the study site; * Born outside of Canada, and arrived in the province of Quebec from another province or country to reside temporarily or permanently in the last 24 months; * ART-experienced, that is, with past or current experience of taking ART to treat HIV, with or without treatment interruption(s) for any clinical or personal reason; * Individuals assigned female at birth may be eligible to enter and participate in the study in the following circumstances: * is of non-child-bearing potential defined as either post-menopausal (12 months of spontaneous amenorrhea and 45 years of age) or physically incapable of becoming pregnant with documented tubal ligation, hysterectomy, or bilateral oophorectomy or, * is of child-bearing potential with a negative pregnancy test at Screening (\& baseline visit) and reporting no plans to become pregnant in the next year. Patients with documented historical resistance to HIV-1 reverse transcriptase inhibitors will be eligible, including: M184I/V alone or in combination with up to 2 thymidine analogue-associated mutations (TAMs) (M41L, D67N, K70R, L210W, T215F/Y, or K219Q/E/N/R). Exclusion Criteria: * Pregnant, breastfeeding, or planning to become pregnant; * Current alcohol or substance use judged by the investigator to potentially interfere with participant study compliance; * Active tuberculosis infection; * Acute hepatitis \< 30 days before enrollment; * Known hypersensitivity to B/F/TAF, its metabolite or formulation excipient; * Documented or suspected resistance to integrase inhibitors as per clinical judgment (e.g., history of poor adherence and/or poor virological control on an InSTI-based regimen); * Documented multi-NRTI resistance mutations/substitutions: K65R/N/E, T69 insertion, or 3 or more TAMs (M41L, D67N, K70R, L210W, T215F/Y, K219E/Q); * Any of the following laboratory values at screening: * Alkaline Phosphatase\>3 × ULN * aspartate aminotransferase (AST) \>5 × upper limit of normal * alanine aminotransferase (ALT) \>5 × upper limit of normal * Hemoglobin\<8.0 g/dL * Estimated creatinine clearance (CrCL) ≤30 mL/min/1.73 m2 based on the Cockcroft-Gault equation for creatinine clearance (CLcr) * Platelets\< 50,000/mm3 * Participation or planned participation in any other clinical study (including observational studies) without prior approval from the sponsor; * Any reason, in the opinion of the investigator, which would make the candidate inappropriate for participation in an investigative study involving oral medications (e.g., inability to understand the study information leaflet, to provide written consent); * Concomitant use of drugs with contraindication or drug-drug interactions with B/F/TAF; * Active malignancy requiring acute systemic therapy; * History of or current clinical decompensated liver cirrhosis (e.g., ascites, encephalopathy, or variceal bleedings).