Clinical trial finds Azithromycin has no benefit against COVID-19

Conducted by the Oxford Clinical Trials Research Unit (OCTRU) and the University of Oxford’s Nuffield Department of Medicine, the ATOMIC2 trial investigated if the common antibiotic azithromycin could prevent patients with mild-moderate COVID-19 from getting worse. 

Azithromycin is a safe, inexpensive and commonly prescribed antibiotic that is available worldwide. It has a wide range of antibacterial, anti-inflammatory and antiviral properties, but there were no strong data proving whether it was effective in COVID-19. 

Supported by the NIHR Oxford Biomedical Research Centre (BRC), the ATOMIC2 trial, randomised 298 participants to either azithromycin (500 mg once daily for 14 days) or to standard treatment without azithromycin. The primary endpoint – death or hospitalisation from any cause – was not significantly different between the two groups; neither were rates of respiratory failure, progression to pneumonia, all-cause mortality, and adverse events, including serious cardiovascular events. 

Dr Timothy Hinks, Chief Investigator of the ATOMIC2 trial and an Oxford BRC Senior Research Fellow, said: “Azithromycin is a very valuable antibiotic used the world over for treating a wide range of serious infections, and remains an essential tool for any healthcare system. Its overuse, where not clearly proven to be of benefit, carries a very strong risk of driving the development of multi-resistant bacteria. 

“The ATOMIC2 trial adds to the now very strong set of evidence that azithromycin is not effective in COVID-19 and it is essential it should be preserved for diseases where it is really needed.” 

The findings were posted on SSRN/Preprints with The Lancet.  

As well as the Oxford BRC, the trial was supported by Pfizer and from philanthropic donations provided via the University of Oxford COVID-19 Research Response Fund.