Plasma therapy: The answer to COVID-19?
Story in brief:
Plasma therapy is the new emerging treatment modality that holds promise in the fight against COVID-19.
Plasma therapy involve the transfusion of antibody-containing plasma from COVID survivors to sick patients with COVID-19.
Initial results are mixed, while reports have emerged indicating that several patients have been successfully treated using plasma therapy, recent news of a plasma therapy-associated death has raised questions.
Plasma therapy is currently only authorized for experimental usage.
Currently, there are no approved treatment modalities for COVID-19.
Plasma therapy, a potential treatment for COVID-19 is being touted as one that holds great promise. In fact, doctors and authorities involved in the treatment and management of COVID-19 are asking COVID survivors to come forth and donate Plasma.
“My plasma donation saved three lives, what can be more noble than saving someone’s life?,” said 36-year-old Covid-19 survivor, Tabrez Khan, who was the first to donate plasma in the national capital.
He had heard appeals by Delhi CM Arvind Kejriwal and went to the Institute of Liver and Biliary Sciences on his own to contribute his plasma.
What is Plasma therapy?
Essentially, Plasma therapy involves the collection of Plasma from healthy patients who have recovered from COVID-19, and the transfusion of this plasma to sick patients in hopes of transmitting passive immunity.
Plasma here is the 'liquid' portion of blood which holds blood cells in suspension. Plasma also contains antibodies to infections that an individual has had in the past. Therefore, in theory, transfusing plasma from COVID-survivors to sick patients will afford 'passive' immunity to the sick patients by transferring antibodies from the survivors.
Evidence for Plasma therapy
Convalescent Plasma (plasma recovered from disease survivors) contains antibodies that may help the sick fight the same infection. In an article in The Lancet in February, Chen et al commented on the historical effectiveness of Plasma when used against past epidemics.
Citing multiple studies since 2005, they argued that Plasma therapy had in fact been successful as a treatment modality for 'critically' ill patients suffering from SARS (2002), H1N1 (2009) and Ebola (2014). In each of these situations, overall mortality had been significantly reduced in the group which received Plasma therapy.
Given the similarities the SARS CoV-2 (the virus that causes COVID-19) virus shares with the viruses that caused these infections, there is reason to believe that Plasma therapy could be effective against COVID-19 as well.
Use in treatment of COVID-19 in India
Responding to the promise held by the emerging treatment modality, authorities have been asking COVID survivors to come forth and donate plasma. "We are contacting 1,100 people who have recovered from COVID-19 to donate their plasma to save lives," said Arvind Kejriwal, the Chief Minister of Delhi in a recent press release. He was of course referring to the collection of convalescent plasma for use on an experimental trial basis. The approval for the use of Plasma therapy on an experimental basis was given by the Indian Council for Medical Research (ICMR).
Since the approval of the therapy, several reports of successful treatments have surfaced. By April 24, Delhi's Lok Nayak Jai Prakash Narayan Hospital reported that four patients had successfully been treated using Plasma therapy.
The results, however, have not all been positive. In fact, the first patient to be receive Plasma therapy in Maharashtra, the state with the highest burden of COVID cases, was declared dead on April 30. Responding to this and to other unverified claims on complications associated with Plasma therapy, the ICMR clarified its stance on plasma therapy, stating, that "there are no approved, definitive therapies for COVID-19".
Yet, despite the mixed initial results from these trials, authorities believe that the treatment could hold promise. Clinical trials are underway in different parts of the country including a Phase II Clinical trial in Karnataka with 450 people. These clinical trials require convalescent plasma, which is the basis for the call to donate plasma.
Anuj Sharma, another COVID survivor was recently on the news encouraging the donation of plasma. Speaking about his experience of donating plasma, Anuj Sharma said, "Only a needle prick was done to take plasma, it hurts for few seconds. But I felt no weakness and was sitting normally the next day with the same appetite and lifestyle as before. Due to coronavirus, so many people are presently suffering. I am happy to contribute to ongoing research that may help more patients. People need not fear plasma donation."
Are the clinical trials likely to yield positive results?
Like many of the options already explored for COVID-19, this is one of the options. It may show modest success, good success or no success. Plasma therapy has always been used in the past and in a variety of conditions but almost always the advent of a vaccine or an antibiotic has pushed plasma therapy to the background.
If it proves to be of some success it will be approved for use in regular clinical settings by regulatory and scientific bodies. If approved for use it will definitely buy some time and save a few lives till a vaccine is available or herd immunity is developed.
It is a promising solution at the present gloomy situation, but till we have reliable evidence on utility unregulated use is to be avoided, as random use does not contribute meaningfully to the database from which a useful conclusion can be drawn. A lot of studies are going on the world over on its use, and hopefully, we will soon know the answer.