Efficacy, Safety, and ToLerability of Switching to A Two-Drug Regimen With DTG/3TC Compared to Maintaining A Three-Drug REgimen With BIC/FTC/TAF or DTG/3TC/ABC in ViroLogically SupprEssed PeopLe Living With HIV After 24 and 48 Weeks of Follow-Up

Since the identification of the human immunodeficiency virus (HIV), developing effective, safe, and well-tolerated antiretroviral therapy (ART) for people living with HIV (PLWH) has been a global health priority. Advances in ART have significantly improved the prognosis for PLWH, achieving life expectancies comparable to the general population. However, three-drug regimens, such as bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF) or dolutegravir/lamivudine/abacavir (DTG/3TC/ABC), are associated with metabolic, renal, and cardiovascular adverse effects, particularly in the Mexican population, which has a high prevalence of metabolic syndrome.

Clinical trials, including GEMINI, TANGO, SALSA, RUMBA, PASO DOBLE, and DYAD, have demonstrated that two-drug regimens, such as dolutegravir/lamivudine (DTG/3TC), offer comparable virological efficacy and improved tolerability. Reducing the pharmacological burden may minimize adverse effects while maintaining viral suppression. The impact of metabolic disturbances on fat weight gain remains a controversial issue.

Objectives General Objective To compare the effectiveness, safety, and tolerability of switching to a DTG/3TC regimen versus continuing BIC/FTC/TAF or DTG/3TC/ABC in virally suppressed PLWH at 24 and 48 weeks of treatment.

Secondary Objectives

• Assess changes in lipid profile, body mass index (BMI), and abdominal circumference.
• Evaluate alterations in glucose metabolism.
• Measure changes in blood pressure and cardiovascular risk using Framingham and AHA/ACC scales.
• Analyze changes in body composition (fat, water, muscle).
• Document adverse events associated with ART. Study Design This is a phase 4, randomized, controlled, open-label, single-center clinical trial conducted at the Hospital de Infectología, National Medical Center "La Raza." The study employs a non-inferiority design with follow-up assessments at 24 and 48 weeks. The study will enroll 156 PLWH aged ≥18 years who are on ART with BIC/FTC/TAF or DTG/3TC/ABC and have maintained virological suppression (HIV-1 RNA <50 copies/mL) for at least 48 weeks. Participants will be randomized in a 2:1 ratio: 104 to switch to DTG/3TC and 52 to continue their current regimen (control group).

Inclusion criteria

• Age ≥18 years.
• Virological suppression (HIV-1 RNA <50 copies/mL) for ≥48 weeks.
• Estimated glomerular filtration rate (eGFR) ≥60 mL/min.
• Signed informed consent. Exclusion Criteria
• Pregnancy or breastfeeding.
• Hepatitis B or C coinfection.
• Active malignancy.
• Use of recreational drugs or medications with significant interactions with ART.

Procedures Following approval by the local ethics committee, participant recruitment will commence. Participants will be followed continuously for 48 weeks. Data will be collected on efficacy (viral suppression), safety (adverse events), and tolerability (patient-reported outcomes and clinical assessments).

Data Management and Statistical Analysis

Patient data will remain confidential and accessible only to study investigators. Data will be recorded in an SPSS database. Statistical analyses will include:

• Kolmogorov-Smirnov test for normality.
• χ² test for categorical variables.
• Student's t-test or Mann-Whitney U test for continuous variables, as appropriate.
• ANOVA for group comparisons.
• Paired tests for within-group changes. A significance level of p ≤ 0.05 will be applied.

Feasibility The Hospital de Infectología, National Medical Center "La Raza," has the necessary infrastructure, trained personnel, and access to study medications to conduct this trial. The study is independent and not sponsored by any pharmaceutical company.

Inclusion criteria

• PLWH aged over 18 years.
• Virologically suppressed for at least 48 weeks prior to study enrollment.
• On ART with Bictegravir/Emtricitabine/Tenofovir Alafenamide (BIC/FTC/TAF) or Dolutegravir/Lamivudine/Abacavir (DTG/3TC/ABC).
• No history of virologic failure.
• Willing to participate in the study.
• Signed written informed consent.
• HIV-1 RNA <50 copies/mL within 4 weeks prior to randomization.
• eGFR by CKD-EPI ≥60 mL/min.

Exclusion criteria

• Pregnant or breastfeeding patients.
• Known allergies to any component of the antiretroviral regimens.
• Coinfection with hepatitis B and/or hepatitis C virus.
• Concomitant medications that interact with any component of the ART regimens.
• Diagnosis of malignancy prior to randomization.
• Use of recreational drugs with anorexigenic potential (crystal meth, methamphetamines, cocaine) within 60 days prior to randomization.