By Naomi Kitur and Faith Atieno

Convalescent plasma, a transfusion of blood plasma from someone who has recovered from COVID-19, is not recommended for patients with non-severe COVID-19, says World Health Organization (WHO).

Despite its prior promise, current evidence shows that it does not improve survival nor reduce the need for mechanical ventilation, and it is costly and time-consuming to administer.

The only exception given by WHO is the use of convalescent plasma in randomized controlled trial (RCT), for severe and critical patients with COVID-19.

The recommendation for patients with non-severe illness reflects the WHO panel’s view that drug treatment in patients with a low risk of mortality and other important clinical outcomes is not justified.

However, the experts acknowledged that although convalescent plasma should not be used routinely in any patients, regardless of how severely ill they are, there was sufficient uncertainty in patients with severe and critical illness to warrant continuation of RCTs.

The recommendations are deduced from current evidence from 16 trials involving 16,236 patients with non-severe, severe, and critical covid-19 infection, that shows it does not improve survival nor reduce the need for mechanical ventilation.

The panel considered a combination of evidence assessing relative benefits and harms, values and preferences, and feasibility issues before arriving at the commendations. The strong recommendation for patients with non-severe illness reflects the panel’s view that drug treatment in patients with a low risk of mortality and other important clinical outcomes is not justified.

They also noted several practical challenges, such as the need to identify and test potential donors, as well as collect, store and administer donor plasma, which they say further limits its feasibility and applicability.

The mentioned patients are part of a living guideline, developed by the WHO with the methodological support of MAGIC Evidence Ecosystem Foundation, to provide trustworthy guidance on the management of virus and help doctors make better decisions with their patients.

According to WHO living guidelines are useful in fast moving research areas like covid-19 because they allow researchers to update previously vetted and peer reviewed evidence summaries as new information becomes available.