Tenofovir tied to lower risk of severe COVID-19 in HBV patients

Patients with chronic hepatitis B virus (HBV) infection who were treated with tenofovir had a lower risk of developing severe COVID-19 illness than those treated with entecavir, according to a study presented at the EASL International Liver Congress (ILC) 2021.

Among 4,736 patients with HBV identified from a Spanish database, patients treated with tenofovir were significantly less likely to develop severe COVID-19 illness after infection compared with those who were on entecavir (6 percent vs 36 percent; p<0.01). [ILC 2021, abstract PO-1449]

The risk of ICU admission was also lower in tenofovir-treated patients than those receiving entecavir (0 percent vs 10 percent; p=0.01). 

Similarly, the incidence of ventilator support (3 percent vs 20 percent; p<0.01), length of hospital stay (3.1 vs 10.8 days; p<0.01), and death rates (1.5 percent vs 10 percent; p=0.08) were all substantially reduced in tenofovir-treated patients vs the entacavir group. 

“Tenofovir seems to exert a protective effect in patients with chronic HBV infected by COVID-19,” said lead author Dr Beatriz Mateos Muñoz of the Hospital Universitario Ramón y Cajal at the University of Alcalá in Madrid, Spain.

As previous studies on HIV-positive patients have shown that the risk of contracting COVID-19 and its related hospitalization was lower in patients treated with tenofovir/emtricitabine vs those on other therapies, the researchers sought to understand if the same could be seen for patients with HBV. [Ann Intern Med 2020;173:536] They therefore compared outcomes of HBV patients treated with the antiviral tenofovir vs entecavir. Severe COVID-19 was defined by the presence of acute respiratory distress syndrome, bilateral severe pneumonia, sepsis, or septic shock.

Participants in the analysis were of 4,736 adults with chronic HBV across 28 Spanish hospitals identified from clinical database — of which 117 were diagnosed with COVID-19 based on positive PCR test results (2.5 percent). Among the COVID-19-positive patients, 60 were receiving tenofovir therapy and 50 were on entecavir for chronic HBV treatment.   

Compared with patients receiving tenofovir, however, a greater proportion of patients on entecavir were obese (22 percent vs 9 percent), had diabetes (32 percent vs 12 percent), ischaemic cardiopathy (14 percent vs 3 percent), or arterial hypertension (44 percent vs 18 percent; p<0.05 for all) at baseline. They also tended to have more severe or advanced fibrosis stage (F3–F4) than the tenofovir group at baseline (35 percent vs 18 percent; p=0.06).

Nonetheless, the risk of severe COVID-19 remained significantly reduced by sixfold in the tenofovir group compared with the entecavir group, even after multivariate adjustment for age, sex, multiple comorbidities, obesity, and fibrosis stage (adjusted odds ratio, 0.17, 95 percent confidence interval, 0.04–0.67; p=0.01).

Overall, 35 percent of the COVID-19-positive patients were hospitalized, while 4.3 percent required admission to ICU and 5.1 percent had died.