On Jan. 15, 2021, Oxford University announced that on advice of the independent Data Monitoring Committee (DMC), recruitment to the convalescent plasma arm of the RECOVERY trial had closed.

The RECOVERY trial was established as a randomised clinical trial to test a range of potential treatments for COVID-19. Since May 2020, the RECOVERY trial had included a randomised comparison of convalescent plasma vs. usual care alone. Convalescent plasma was widely used as a treatment for COVID-19 but to date there was no convincing evidence of the effect of convalescent plasma on clinical outcomes in patients admitted to hospital with COVID-19.