Promising Approach to a COVID-19 Vaccine
Although it is reassuring to know COVID-19 vaccines are on the way (the Russians say they are already here), multiple questions remain about these drugs and what effect they will have on the current pandemic.
Although it is reassuring to know COVID-19 vaccines are on the way (the Russians say they are already here), multiple questions remain about these drugs and what effect they will have on the current pandemic. Will they be effective? How long will immunity last? Will they be safe? Who will pay for mass immunization? Can the vaccines be produced quickly and in adequate volume? What infrastructure do we need to deliver these drugs?
Amid these questions, one type of therapy — monoclonal antibodies (mAbs) — has been largely, but not completely, overlooked. In the case of COVID-19, their mechanism of action is to block the coronal spikes on the virus and thus prevent attachment to the patient’s cells. This approach is being used successfully for treating leukemia, rheumatoid arthritis and Crohn’s disease, as well as for organ transplant patients to reduce the incidence of rejection. These medications can be quickly mass produced and are capable of targeting a specific antigen — in this case, the virus responsible for COVID-19. One possible application is as a bridge for use until a more successful vaccine is found and distributed.
UNDER LABORATORY CONDITIONS, PLACING THESE ANTIBODIES INTO A COVID-19 CELL CULTURE SUCCESSFULLY NEUTRALIZED THE VIRUS
The general principle is similar to the use of plasma from individuals who have recovered from COVID-19, but mAbs are potentially even more effective. Donated plasma con- tains multiple mAbs, some of which may be ineffective against the virus. The mAbs currently under study concentrate on one task — inactivating the virus. In this case, it is hoped that a specific mAb can be manufactured and used either to prevent disease or attack the virus in infected individuals. One downside is the immunity provided by these drugs is transient, usually a month or so at best, so serial injections may be needed.
Studies are ongoing to develop mAbs to attack COVID-19. A recent article in The Wall Street Journal explored the status of one of these medications. It highlighted research led by Conrad Chan, PhD, of DSO National Laboratories in Singapore. Chan’s team harvested white blood cells from thousands of patients who had recovered from COVID-19, ultimately isolating five strains of white blood cells that aggressively produced antibodies. Choosing the strongest responder of the five, investigators introduced a protein that forced the white blood cells to develop
antibodies to the virus. Under laboratory conditions, placing these antibodies into a COVID-19 cell culture successfully neutralized the virus. The antibody has now been cloned and tested for efficacy in animals. The initial tests proved successful and human trials are underway.
Chan’s laboratory is not the only one developing these antibodies. The National Institutes of Health is conducting similar research. In partnership with Eli Lilly and Company, it is sponsoring clinical trials of an antibody they hope can be used for patients with moderate disease to reduce the need for hospitalization.
If several mAbs prove successful against COVID-19, it would allow clinicians to chose the best fit for each patient. While it would be illogical to assume the process of developing and delivering a successful vaccine will be without problems, if mAbs prove effective, this approach could decrease morbidity and save lives.
Thomas G. Wilson Jr., DDS
Editor in Chief
From Decisions in Dentistry. November 2020;6(10):4.