Abstract Body

Effective, safe, and affordable antivirals are needed for COVID-19. Several lines of reseach suggest that tenofovir may be effective against COVID-19 but no large-scale human studies with appropriate adjustment for comorbidities have been conducted. We describe the incidence, clinical severity and mortality of laboratory-confirmed SARS-CoV-2 infection by antiretroviral therapy (ART) among HIV-positive individuals with virological control adjusting for key potential confounders including hypertension, diabetes, chronic renal disease, cardiovascular disease, and treatment with immunosuppressants or corticosteroids.

We studied HIV-positive individuals on ART in 2020 at 69 HIV clinics in Spain from February 1 to December 31. These 69 clinics serve approximately 44% of all persons on ART with virological suppression in Spain. We collected data on sociodemographics, ART, CD4-cell count, HIV-RNA viral load, comorbidities and the following outcomes: laboratory-confirmed SARS-CoV-2 infection, COVID-19 hospitalization, intensive care unit (ICU) admission and death. We compared 48-week risks, relative risks, relative differences and 95% confidence intervals (CI) for individuals receiving tenofovir disoproxyl fumarate (TDF)/emtricitabine (FTC), tenofovir alafenamide (TAF)/ FTC, abacavir (ABC)/lamivudine (3TC), and other regimes. All estimates were adjusted for clinical and sociodemographic characteristics via inverse probability weighting.

Of 51,558 eligible individuals, 39.6% were on TAF/FTC, 11.9% on TDF/FTC, 26.6% on ABC/3TC, 21.8% on other regimes. There were 2,402 documented SARS-CoV-2 infections (425 hospitalizations, 45 ICU admissions, 37 deaths). Compared with TAF/FTC, the estimated risk ratios (RR) (95% CI) of hospitalization were 0.66 (0.43, 0.91) for TDF/FTC and 1.29 (1.02, 1.58) for ABC/3TC, the RRs of ICU admission were 0.28 (0.11, 0.90) for TDF/FTC and 1.39 (0.70, 2.80) for ABC/3TC, and the RRs of death were 0.37 (0.23, 1.90) for TDF/FTC and 2.02 (0.88-6.12) for ABC/3TC. The corresponding RRs of hospitalization for TDF/FTC were 0.49 (0.24, 0.81) in individuals ?50 years and 1.15 (0.59, 1.93) in younger individuals.

Our findings suggest that, compared with other antiretrovirals, TDF/FTC lowers COVID-19 severity among HIV-positive individuals with virological control. This protective effect may be restricted to individuals aged 50 years and older. Confirmatory randomized trials of TDF/FTC for the prophylaxis and early treatment of COVID-19 are warranted.