Can antibodies prevent the spread of novel coronavirus?
Antibodies are the body's first line of defence against infection. Presence of antibodies can also detect if a person has already battled the infection and has now gathered immunity against the same. For the same, Sero surveillance is being done in several places to ascertain how many people have been exposed to COVID-19.
Now, following an experimental approach, a group of scientists are exploring whether harvested antibodies could act as a preventive tool against the novel coronavirus infection.
While there is no approved preventive cure for COVID-19 right now, at least 110+ medical groups and researchers are working on creating a vaccine to inoculate people against the deadly disease, 5 of which are in the later stages of trials. The antibody study could thus be a game-changer.
The study
The new study aims to test whether antibodies from a COVID+ positive patient could help prevent the chances of infection or reinfection in someone who has been exposed to the virus.
The experimental study, which is being carried out at John Hopkins University, USA makes use of the convalescent plasma- purified blood serum which contains antibodies found in people who have battled a brush with COVID-19.
How does Convalescent plasma therapy help?
One of the first participants in the study is a physician from the university school of medicine, who, unfortunately, had close contact with his COVID+ daughter. While he and his wife, both in his 60s, tested negative in repeated tests, they still belong to a high-risk group due to the level of exposure and hence, made for an ideal candidate for the study.
Currently, convalescent plasma therapy, which works like a blood transfusion is only being tested as an experimental therapy and not a preventive cure for the virus. Many places have set up plasma banks, where healthy recovered patients donate their plasma, which is then, used to treat COVID patients and aid faster recovery. It should be noted that CPT or plasma therapy is still under research and not a fool-proof treatment plan for coronavirus.
How is the study being carried out?
The participants in the study have been split into groups of two. One half will be administered blood plasma from patients who have contracted COVID-19, while the other half will be transfused with plasma collected from people before the occurrence of the pandemic, i.e., from people who deposited plasma who have had no brush with the virus and hence, would be lacking COVID protecting antibodies. It will be a randomized blind trial wherein neither the doctors involved, nor the participants will have information about what they are being dosed with.
The investigation is being currently underway and Dr Shmuel Shoham, who is one of the lead researchers focussing on the study is planning to enrol more participants and expand the trial to more cities in the USA. However, he believes that if the study starts to show good results, the need to increase testing pool may not be needed. Preliminary results from the study will be available by September.
Can it offer long-term protection?
Researchers are also involved in another study which will determine whether antibody-rich convalescent plasma would be able to protect people who have been infected by the virus but aren't sick (i.e. asymptomatic) from developing serious complications in the future.
Scientists believe that the usage of this therapy could help protect and prevent populations from the risk of COVID-19 in the absence of a COVID-19 vaccine. With a good vaccine far from being used, such a novel approach could be key to reopening of schools, gyms and give people the confidence to return back to normalcy, considering that the virus may never really go away.
Antibody transfusion has been used before
Similar strategies wherein antibodies are used to stop or "fully prevent" the virus from coming back have been explored in the past with diseases like rabies, hepatitis B, botulism and a rare type of respiratory infection affecting young kids. It has also been used in times of the flu outbreak, but no benefit was observed.
There are also reports making rounds that medical science companies may be working on therapies to sell and manufacture antibodies in the future, which won't be extracted from recovered patients and will have a pricey rate.