Commonly used to treat bacterial infections ranging from pink eye to pneumonia, the antibiotic azithromycin emerged as an early candidate for treating bacterial co-infections tied to SARS-CoV-2.
But a recent clinical trial of the common antibiotic found that the drug is not an effective therapy for hospitalized COVID-19 patients.
The U.K.-based RECOVERY trial had previously found that the common steroid dexamethasone showed promise in treating severe COVID-19 cases but that the antimalarial drug hydroxychloroquine was not effective.
In the study, 2,582 received azithromycin while 5,182 patients received the standard of care. The patients in the azithromycin arm received 500 mg of the drug once daily by mouth or intravenously.
After 28 days, the death rate for both groups was 19%. There was also no difference in length of hospitalization duration between the two groups.
The trial also showed no evidence of benefit for patients requiring mechanical ventilation.
Given the disappointing results, the steering committee overseeing the trial agreed to close it on Nov. 27.
The data for the clinical trial has been published on the medRxiv website.
Azithromycin may still be potentially useful for treating moderate COVID-19 patients.
The RECOVERY trial is also examining the potential of other COVID-19 treatments such as convalescent plasma and a monoclonal antibody cocktail from Regeneron that recently won emergency use authorization in the U.S.