Novel Coronavirus disease 2019, commonly referred to as COVID-19 pandemic has affected almost every country in the world, and mankind is scrambling to find sustainable preventive and curative solutions for this condition. More than 4 million people have been diagnosed with this condition and almost 300,000 people have lost their lives till as of the first week of May 2020 and it is being seen as a big threat to the health of people globally.
There is no specific antiviral therapy available to treat COVID-19 patients and this is leading to rapid loss of lives on a daily basis. There have been numerous attempts at research and numerous trials are underway in finding treatment modalities for the ongoing pandemic COVID-19. One interesting modality that has attracted global attention and could be effective is the “convalescent plasma therapy”, which involves transferring the antibodies from a person who has recovered from the coronavirus disease to a critically-ill patient, to help boost their immunity.
Convalescent plasma therapy has been found to be safe and effective against SARS, MERS, and H1N1 viral infections over the past two decades and the same hypotheses are being applied for SARS-COV-2 infection that belongs to the same class of viruses (corona).
What is Convalescent Plasma?
Human blood comprises two main components – the cells and the fluid. Plasma refers to the fluid component of blood. Proteins like antibodies are present in the plasma. People who have recovered from COVID-19 have antibodies against it in their plasma and this refers to convalescent plasma.
Researchers want to use the plasma of COVID-19 recovered patients to treat existing COVID-19 patients. Plasma extracted from blood donated by recovered patients is used for convalescent plasma therapy.
How Does Convalescent Plasma Therapy Work?
Whenever an individual gets infected by a new pathogen like a virus or bacteria for the first time, his/her body’s immune system gets activated and it tries to kill the invading agents by various means.
One of the mechanisms involves the production of proteins called ‘antibodies’ that are released by certain immune system cells in the blood. When these cells come in contact with the new pathogen then they produce certain specific proteins called antibodies that carry identity marks specific to that particular pathogen and help the immune system recognise and locate those pathogens in the body.
These antibodies travel around the body in the bloodstream and whenever a pathogen comes in contact with a matching antibody, it raises a sort of an alarm leading to a cascade of immune response wherein the body’s immune system tries to kill the invading pathogen.
Convalescent plasma of people who recovered from COVID-19 is found to contain antibodies against the novel coronavirus and researchers are trying to see if transfusing convalescent plasma helps existing patients recover from the disease. The antibodies in the plasma from a recovered COVID-19 patient will enable the immune system to identify and fight the coronavirus infection.
A Promising Treatment Modality for Cancer Patients
Recently, a private hospital in Bengaluru, Karnataka, was granted approval to conduct clinical trials on coronavirus patients using plasma therapy. Cancer patients and those with compromised immunity who are affected with COVID-19 are likely to be susceptible to severe infections, and plasma therapy has shown some promise in initial studies.
It is still to be seen if plasma therapy is foolproof, safe, and effective before we use it for cancer patients as any untoward reaction can lead to deterioration of the health condition of a patient.
In a plasma therapy trial that was conducted in a 49-year old patient at a hospital in New Delhi who had developed pneumonia and respiratory failure, the patient is now recovered and discharged after successful treatment.
The therapy, however, is in its experimental stages, and have shown promising results in initial trials. The scope looks positive, and if this proves to be safe and effective, more health institutions will start using plasma therapy from early to advanced stages of COVID-19 leading to better recovery rates.
How is the Trial Planned in India?
While the therapy is already being adopted by countries like South Korea, United States, China, and the UK, India has also granted approval from CDSCO (Central Drugs Standard Control Organisation) to begin trials in eligible institutes.
“People who have crossed 21 – 28 days since recovery COVID-19 and healthy with no underlying diseases such as diabetes, blood pressure, heart disease, cancer are considered,” says Dr. SK Sarin, Head of Delhi Government COVID Panel.
The patient’s blood will be taken and transfused to a patient who is critically ill with severe respiratory problems, in the aim of boosting their immunity and fighting the infection.
A donor can provide up to 400ml of plasma and this can be used to treat 2 patients as 200ml is found to contain adequate quantities of anti-COVID-19 antibodies.
Currently, the trials are being conducted in 12 Indian states.
If You Have Recovered from COVID-19 – How Safe is Plasma Donation?
The donors donate blood like any blood donation procedure. Plasma is separated from the cellular component of blood before being transfused in patients.
“In the procedure, we just take the plasma and the other cells go back into the blood. Hence, there is no decrease in haemoglobin and you do not feel weak”, adds Dr. Sarin.
There have been calls from ICMR (Indian Council of Medical Research) and various state governments asking people who have recovered from COVID-19 to step out and volunteer and donate their plasma to help treat critically ill people.
NOTE: Please note that plasma therapy is still an investigational therapy and is only being used under research protocols in approved hospitals. We cannot use it for all patients until it is proved to be safe and useful for regular use for all patients.