Published: 14 December 2020
The NIHR-supported RECOVERY trial has found no clinical benefit from the antibiotic azithromycin for hospitalised patients with severe COVID-19.
Azithromycin is an antibiotic known for its anti-inflammatory properties which is already used to treat chronic inflammatory lung disease, or chest infections such as pneumonia.
Inflammation, caused by an overly-active immune response, is a key feature of severe COVID-19. Azithromycin was considered a potential treatment for COVID-19 and investigated through an arm of the RECOVERY trial to assess whether the drug had a meaningful benefit amongst hospitalised patients with COVID-19.
A preliminary analysis of the data has shown no meaningful clinical benefit of azithromycin in the hospitalised COVID-19 patients randomised to this treatment arm. The data showed no significant difference in the primary endpoint of 28-day mortality (19% azithromycin vs. 19% usual care). While researchers found no evidence of beneficial effects on the risk of progression to mechanical ventilation or length of hospital stay.
The results were consistent in different subgroups of patients. However it is not possible to make conclusions about the effectiveness of azithromycin in patients in the community.
The azithromycin arm of the trial was closed on 27 November, following confirmation from the Trial Steering Committee that sufficient patients had been enrolled to establish efficacy data for this treatment arm. A total of 2582 patients were randomised to azithromycin and compared with 5184 patients randomised to usual care alone. Patients entered the study an average of 8 days after the onset of symptoms. Follow-up is complete for 73% of the participants and will be complete by the end of the year.
Prof Nick Lemoine, Medical Director of the NIHR Clinical Research Network, said: “Although it might seem disappointing that the data from this particular arm of the RECOVERY trial is negative, these latest results are in fact another important development in the fight against COVID-19. The data convincingly proves that the antibiotic azithromycin - once considered a potential treatment candidate for severely ill COVID-19 patients as a result of its anti-inflammatory properties - has no clinical benefit, and this will inform clinical practice around the world.
“The RECOVERY trial has once again provided important, practice-changing evidence which will enable clinicians to focus treatment decisions on other areas. It is only through conducting robust clinical trials that important evidence on emerging treatment candidates can be established - and the medical science around COVID-19 advanced.”
Martin Landray, Professor of Medicine and Epidemiology at the Nuffield Department of Population Health, University of Oxford, and Deputy Chief Investigator, said: “We have seen time and again during this epidemic the importance of large randomised clinical trials in determining which of the many promising treatments deliver real benefits for patients.
“Once again, we thank the thousands of NHS doctors, nurses, pharmacists, and research staff who have contributed to the RECOVERY trial and the quest for knowledge about how best to reduce the terrible burden of this disease.
“Above all we must thank the 20,000 patients who have taken part in this extraordinary and truly world-leading effort. The improved care of COVID patients today is thanks to the selfless contribution of RECOVERY participants in the past – and in turn, the care of patients tomorrow will be better as a consequence of those volunteering today. Thank you.”
The RECOVERY trial is the world’s largest trial of potential COVID-19 treatments - with over 20,000 participants enrolling since it opened in March. The trial is jointly funded by UKRI and NIHR, while delivery of the trial is supported by the NIHR Clinical Research Network.