COVID-19: Convalescent Plasma Helps Prevent Disease Progression in Older Adults
Convalescent plasma with high SARS-CoV-2 antibody titers can help prevent progression to severe COVID-19 in older adults with mild disease, according to a New England Journal of Medicine study.
Some 160 adults aged 65 and older in Argentina who tested positive for SARS-CoV-2 within 48 hours of developing mild COVID-19 symptoms (e.g., fever, dry cough, fatigue) were randomized to receive an infusion of high-antibody-titer convalescent plasma (IgG above 1:1000 against SARS-CoV-2 spike protein) or placebo. Infusions were given within 72 hours of symptom onset and lasted about 1.5–2.0 hours.
The primary endpoint — development of severe respiratory disease by day 15 — was roughly halved with plasma infusion (16% of plasma recipients vs. 31% of placebo recipients). The researchers calculated that seven older patients would need to be treated to prevent one case of severe respiratory disease.