Happy Tuesday, friends.
You’ve probably already heard that the Food and Drug Administration (FDA) has recently given Emergency Use Authorization (EUA) for convalescent plasma for the treatment of severe COVID-19, but what does that mean, and how does convalescent plasma work?
Emergency Use Authorization does not actually mean that that the FDA has fully approved a treatment or medication. It instead means that the FDA feels that public benefit outweighs potential harm and is making it possible for doctors to use an unapproved medication during a declared state of health emergency. Remdesivir also received a EUA a few months ago. But never fear, these treatments have passed safety testing and are generally also in clinical trials to establish effectiveness.
What is Convalescent Plasma? Plasma is the pale-yellow liquid portion of your blood (that remains after the red blood cells have been separated out) that can be easily replaced by the body. It consists mainly of water and proteins. Convalescent plasma is what it sounds like – plasma that was donated by people who have recovered from COVID-19 (usually at least 28 days post infection).
The plasma contains antibodies. A previous post covers how vaccines and antibodies work, but antibodies, are large, Y-shaped proteins produced mainly by plasma cells that are used by your body’s immune system to fight off infections. The idea is that persons with COVID-19 produced these antibodies, which helped them recover, and thus giving their antibodies to other people suffering from COVID-19 will help those people, too.
Is it safe? Yes. Convalescent plasma is treated like any other blood product. It is tested for safety by the blood bank and also completely cross-matched to the person receiving the plasma to ensure that the plasma is compatible with the recipient.
Does it work? Clinical trials are underway to completely answer that question, but anecdotal evidence does show that very ill patients given convalescent plasma do improve. The caveat to remember is that convalescent plasma isn’t a standardized treatment or vaccine. It is a blood product produced by individuals, so the amount and type of antibodies produced by each person varies widely.
Bottom line. Convalescent plasma is given to hospitalized patients who have serious coronavirus disease. It is one of the tools and treatments available to us now, while vaccines and other treatments are still under development.