July 22, 2020

expert reaction to study looking at neutralising antibodies directed to multiple epitopes on SARS-CoV-2 spike

A study, published in Nature, has looked at neutralising antibodies produced by COVID-19 patients and their potency.

Prof Eleanor Riley, Professor of Immunology and Infectious Disease, University of Edinburgh, said:

“This paper reports findings similar to several other recent studies from laboratories around the world.  These studies all demonstrate that it is possible to isolate antibody-producing cells from the blood of convalescent COVID-19 patients, grow them in the laboratory and harvest the antibodies they produce.  All the studies find, as expected, that antibodies derived from different patients, and from different individual cells within each patient, vary in their potency as determined by their ability to block virus entry into host cells (their “neutralisation” capacity) and that a subset of these antibodies (that bind to defined parts of the virus spike protein) are very, very effective at neutralisation.

“Together, these studies are the first steps in the development of antibody-based drugs for the treatment or prevention of COVID-19.  The cells can be grown in the lab and used to produce antibodies.  Also, the genes encoding these antibodies can be isolated from the cells and used as the basis for production of synthetic antibodies.  These approaches are routinely used to produce therapeutic antibodies for treatment of autoimmune and other inflammatory diseases and there is thus a proven route for their development, regulation and use.  The methods are well established and the manufacturing capability exists.  Once made, the antibodies would need to be tested in clinical trials to find out if they are safe and beneficial; prior experience suggests that they are likely to be beneficial as long as they are administered early enough in the infection (i.e. during the acute phase of the infection when there is still virus present).  The approach is similar to the use of convalescent plasma except that these antibodies would likely be at higher concentration, would be more potent and – as they contain fewer extraneous serum proteins – cause fewer side effects.

“However, these drugs do tend to be rather expensive and thus are likely to be reserved for treatment of severely ill patients or prevention of COVID-19 in high risk individuals.  Also, as the antibodies will wane over a period of days or weeks after treatment, they are not really suitable for long term prevention.  Long term prevention of COVID-19 in the general population will, hopefully, be achieved by vaccination but, in the meantime, therapeutic anti-COVID-19 antibodies may be able to play a useful role in reducing the morbidity and mortality of severe COVID-19.”

‘Potent neutralizing antibodies directed to multiple epitopes on SARS-CoV-2 spike’ by Lihong Liu et al. was published in Nature on Wednesday 22 July 2020.

DOI: 10.1038/s41586-020-2571-7

https://www.nature.com/articles/s41586-020-2571-7

All our previous output on this subject can be seen at this weblink:

www.sciencemediacentre.org/tag/covid-19

Declared interests

Prof Eleanor Riley: “No COIs to declare.”