Could blood plasma from those who recovered from Covid-19 help others with weakened immune systems?

A clinical trial in the UK is exploring whether people who have extraordinary levels of Covid-19 antibodies from infection and vaccination can help those most vulnerable to the virus.

According to the NHS, the hope is that blood transfusions from these “super donors” will help the immunocompromised. 

A small test study at the start of the pandemic found five critically ill Covid-19 patients who were given plasma containing antibodies saw an improvement in their condition. However, its authors stressed the need for a full trial and more study on the subject.

“In this preliminary uncontrolled case, five critically ill patients with Covid-19 and acute respiratory distress syndrome, administration of convalescent plasma containing neutralising antibody was followed by improvement in the patients’ clinical status. The limited sample size and study design preclude a definitive statement about the potential effectiveness of this treatment, and these observations require evaluation in clinical trials.”

One trial and a study later found blood from those who recovered from Covid-19 did not help at all.

“We are confident that convalescent plasma has no benefits for the treatment of people with moderate to severe Covid-19,” the study said.

However, another trial looking at people with exceptionally high antibodies gave enough hope for it to be re-examined.

More than a dozen hospitals across the UK will take part in the trial.

“It could be of particular use in the developing world, where access to more expensive treatments is limited,” said Prof Lise Estcourt, head of NHS Blood and Transplant’s clinical trials unit and chair of the new trial.