Dimethyl fumarate in patients admitted to hospital with COVID-19 (RECOVERY): a randomised, controlled, open-label, platform trial

Background Dimethyl fumarate (DMF) is an anti-inflammatory drug that has been proposed as a treatment for patients hospitalised with COVID-19

Methods This randomised, controlled, open-label platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]), is assessing multiple possible treatments in patients hospitalised for COVID-19. In this initial assessment of DMF, performed at 27 UK hospitals, eligible and consenting adults were randomly allocated (1:1) to either usual standard of care alone or usual standard of care plus DMF 120mg twice daily for 2 days followed by 240mg twice daily for 8 days, or until discharge if sooner. The primary outcome was clinical status on day 5 measured on a seven-point ordinal scale, assessed using a proportional odds model. Secondary outcomes were time to sustained improvement in clinical status, time to discharge, day 5 peripheral blood oxygenation, day 5 C-reactive protein, and improvement in day 10 clinical status. The trial is registered with ISRCTN (50189673) and clinicaltrials.gov (NCT04381936).

Findings Between 2 March 2021 and 18 November 2021, 713 patients were enrolled in the DMF evaluation, of whom 356 were randomly allocated to receive usual care plus DMF, and 357 to usual care alone. 95 (common odds ratio of unfavourable outcome 1.12; 95.85-1.46; p=0.42). There was no significant effect of DMF on any secondary outcome. As expected, DMF caused flushing and gastrointestinal symptoms, each in around 6 but no new adverse effects were identified.

Interpretation In adults hospitalised with COVID-19, DMF was not associated with an improvement in clinical outcomes.