Effects of Biktarvy on CFR in Stable HIV Patients

Positron emission tomography (PET) imaging allows precise and reproducible quantification of myocardial blood flow, thereby providing a direct assessment of coronary vascular health. Coronary flow reserve (CFR, calculated as the ratio of peak hyperemic myocardial blood flow over that at rest) is emerging as a powerful quantitative prognostic imaging marker of clinical cardiovascular risk. CFR provides a robust and reproducible clinical measure of the integrated hemodynamic effects of epicardial coronary artery disease (CAD), diffuse atherosclerosis, vessel remodeling, and microvascular dysfunction resulting from endothelial cell dysfunction on myocardial tissue perfusion across the entire coronary circulation. These processes have direct relevance to the underlying vascular pathobiology in patients with HIV infection. Consequently, quantitative CFR provides a unique opportunity to examine the potential impact of novel therapies on the biology of the disease and its association with cardiovascular outcomes. By testing the fundamental concept of whether novel ART therapies in HIV can lead to improved coronary blood flow and myocardial tissue perfusion, TAF-CFR would provide important mechanistic insights of the capabilities of TAF therapy to improve key determinants of clinical risk. This is an open label, multicenter, uncontrolled, single arm pilot study. Patients with stable HIV currently treated with abacavir/lamivudine/dolutegravir STR regimens will be eligible for the B/F/TAF-CFR study. PET scans will be performed after enrollment while on the abacavir/lamivudine/dolutegravir STR regimen and at 24 weeks after the switch to B/F/TAF regimen. Patients will be encouraged to remain on stable medical therapy throughout the enrollment period.