Analytical Treatment Interruption in HIV Trials: Statistical and Study Design Considerations

PURPOSE OF REVIEW: Analytical treatment interruption (ATI) remains an essential component in clinical studies investigating novel agents or combination treatment strategies aiming to induce HIV treatment-free remission or long-term viral control. We provide an overview on key study design aspects of ATI trials from the perspective of statisticians. RECENT FINDINGS: ATI trial designs have evolved towards shorter treatment interruption phases and more frequent viral load monitoring aiming to reduce prolonged viremia risks. Criteria for ART resumption have evolved as well. Common outcome measures in modern ATI trials include time to viral rebound, viral control, and viral set point. SUMMARY: Design of the ATI component in HIV clinical trials is driven by the scientific question and the mechanism of action of the intervention being investigated.