The World Health Organization (WHO) has advised against using plasma containing Covid-19 antibodies to treat patients with the virus, finding it to be ineffective and a waste of resources.
In an advisory published by the BMJ on Monday night, WHO experts warned that "a transfusion of blood plasma from someone who has recovered from covid-19" - known as convalescent plasma therapy - "is not recommended for patients with covid-19."
The organization issued a particularly "strong recommendation" against the therapy for those with mild illness from Covid-19 and a general recommendation against it for those with a severe or critical illness.
"Despite its initial 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 advisory declared, citing evidence from 16 trials and over 16,000 patients.
The US National Institutes of Health made a similar ruling in August, revealing that clinical trials showed the therapy "did not prevent disease progression in a high-risk group of outpatients with COVID-19, when administered within the first week of their symptoms."
Clifton Callaway, M.D., Ph.D., who worked on the trial, said researchers were hoping that the plasma therapy "would achieve at least a 10% reduction in disease progression," but instead observed a reduction of less than 2%.
The US Food and Drug Administration (FDA) issued an emergency use authorization for convalescent plasma therapy in August 2020, however it went on to limit its use in February to only "hospitalized patients with COVID-19 early in the disease course or hospitalized patients who have impaired humoral immunity."