PhotoBio-HIV: Effects of Vascular Photobiomodulation on Inflammatory and Immunological Biomarkers in People Living with HIV/AIDS – Study Protocol for a Randomized, Double-Blind, Placebo-Controlled Clinical Trial

People living with HIV/AIDS (PLWHA), even when on stable antiretroviral therapy (ART), often experience premature aging and comorbidities associated with chronic, low-grade systemic inflammation. Conventional pharmacological strategies have limited effects in modulating this inflammatory state, highlighting the need for safe, accessible, and effective complementary therapies. Photobiomodulation (PBM), a noninvasive technique that uses low-intensity light to influence cellular activity and physiological processes, has shown promising results in modulating inflammation and improving vascular and immune function; however, its effects in PLWHA remain underexplored. This single-center, randomized, double-blind, placebo-controlled clinical trial will include 105 participants with HIV/AIDS on stable ART, allocated into three groups. The intervention will consist of PBM applied over the radial artery for 10 minutes, twice weekly for 4 weeks, with the protocol repeated at months 1, 3, and 5. Blood samples will be collected at seven time points to assess inflammatory, immunological, and coagulation biomarkers, as well as hematological parameters. If effective, vascular PBM may help reduce systemic inflammation and support its use in broader clinical settings. Clinical trial registration: Brazilian Clinical Trials Registry (ReBEC), identifier RBR-3mcg82f; Universal Trial Number (UTN) U1111-1312-7930; registered on December 5, 2024.