Rapid ART Initiation with BIC/FTC/TAF in People Who Inject Drugs in Greece: Results from a Pilot Single-Arm Study of an Integrated Care Model

People who inject drugs (PWIDs) remain underserved in HIV care. Evidence on rapid antiretroviral therapy (ART) for PWID is limited. We evaluated feasibility, effectiveness, safety, and patient-reported outcomes (PROs) for rapid initiation of bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF) supported by a peer navigation in Greece. This is a single-arm, multicenter pilot study including PWIDs (≥18 years) newly diagnosed or relinking after >3 months off ART. Participants started BIC/FTC/TAF on the same day or within 7 days and received peer navigation for 48 weeks. Co-primary endpoints were Week-24 virologic suppression (HIV-1 RNA < 50 copies/mL; FDA Snapshot) and grade 3-4 adverse events (AEs). Secondary endpoints included complete-case suppression at Weeks 24/48, CD4 recovery, retention, and PROs. Outcomes were compared with historical controls from the same centers. Thirty-seven participants were enrolled (83.8% male; median age 33.3 years). Median time to ART was 0 days (vs 78 in controls, <i>p</i> < 0.001). Retention was 67.6% at Week 24 and 54.1% at Week 48. In the primary (FDA Snapshot) analysis, suppression was 62.2% and 54.1% at Weeks 24 and 48; in complete-case analyses, results were 92.0% and 100%, respectively. Mean CD4 count increased by 208 cells/μL (95% CI 141-275) at Week 48. Quality of life improved and symptom burden decreased. No grade 3-4 AEs occurred. Rapid BIC/FTC/TAF with peer navigation eliminated delays to ART and achieved favorable virologic, immunologic, and PROs among those retained, with good tolerability. Despite retention challenges, this model appears feasible for PWID and may help close HIV care gaps toward UNAIDS 95-95-95 targets.