The decision by the United States government to approve the use of convalescent plasma therapy for treating cases of COVID-19 has made international headlines and fuels hope that the treatment may be a cause for optimism in the fight against the pandemic.
The U.S. Food and Drug Administration (FDA) announced earlier this week that emergency authorisation has been granted for the use of plasma therapy to treat COVID-19, the disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or, simply, coronavirus. As explained by BBC News, “the technique uses antibody-rich blood plasma from people who’ve recovered from the disease and has already been applied to 70,000 people in the US – in trials or for the gravely ill.”
However, FDA scientist Denise Hilton said “COVID-19 convalescent plasma should not be considered a new standard of care for the treatment of patients with COVID-19. Additional data will be forthcoming from other analyses and ongoing, well-controlled clinical trials in the coming months.”
Convalescent plasma therapy refers to, to quote The Guardian’s Oliver Millman, the concept that “when people are sickened with a disease, such as COVID-19, their immune systems generate antibodies to fight back. These antibody proteins are found in blood plasma, the liquid that surrounds blood cells. Scientists are able to take blood plasma from someone who has had COVID-19 and isolate the antibodies. These antibodies can then be injected into someone sick with the disease, to help combat it until the patient’s immune system generates enough of its own antibodies and ward off the infection.”
Plasma therapy has been touted as a potential COVID-19 treatment for some time. As my colleague Nicholas Parry reported for Health Issues India in April, “hope may be on the horizon following the publication of new research in China…[that] involved the use of convalescent plasma therapy for those with severe symptoms of the coronavirus. In addition, hospitals in the US have trialled the therapy, with hospitals in Kerala also utilising the therapy.”
Yet, Parry wrote, “it must be noted, however, that the concept of convalescent plasma therapy as a coronavirus treatment is one in its early stages. The research paper from China is well aware of its own limitations, that being the initial trial of only ten individuals. It has positioned the study as the initial stepping stone into further research into the potential therapy given its positive results so far.”
Since then, the conversation surrounding plasma therapy has continued but questions still remain. As Stat reports, “a study released Aug. 13 — but not yet peer-reviewed — suggested that using convalescent plasma to treat patients with severe Covid-19 soon after their diagnosis was associated with a lower likelihood of death. But the study had serious scientific limitations that make interpreting the findings difficult.” It notes that the FDA’s emergency use authorisation regarding plasma therapy is part of a pattern of such authorisations for treatment of COVID-19, such as the allowance for the use of antivirals remdesivir and hydroxychloroquine as a treatment (the latter since withdrawn).
Concurring, the Guardian report outlines that “this trial did not include a placebo group for comparison and the therapy lacks any proof of benefit for Covid-19 from large, randomised studies. Dr Anthony Fauci, the White House’s top infectious disease expert, and Dr Francis Collins, the director of the National Institutes of Health, have both reportedly urged the FDA against a rushed approval of plasma therapy due to the weak supporting evidence of its efficacy.” It cites a memorandum from “an unidentified FDA staffer who reviewed the data [who] said the therapy “meets the ‘may be effective’ criteria” for it to be used on an emergency basis but that further studies are required.”
The use of plasma therapy has enthused some in India. Research in India has suggested the treatment may be effective in alleviating moderate symptoms of COVID-19. The Indian Council of Medical Research (ICMR) conducted a pan-Indian trial of plasma therapy for treating COVID-19 involving 52 institutions. Of these, The Indian Express spoke to principal investigators from 36, of whom 24 described plasma therapy as “effective” (as reported in July).
The Aam Aadmi Party administration in Delhi has been a notable proponent of plasma therapy. A number of Delhiite hospitals have received authorisation to administer plasma therapy from the central government. Accordingly, following the U.S. government’s announcement, Delhi Chief Minister Arvind Kejriwal reacted with ebullience. Referring to convalescent plasma therapy, Kejriwal said “they used to say, back in the day – what America does today, India would do tomorrow. Delhi has changed it. Now – what Delhi did yesterday, America does today. Congratulations Delhiites for achieving this for our country.”
Convalescent plasma therapy does offer hope. However, scientific rigour must be applied. The announcement in the United States may well buoy the enthusiasm surrounding convalescent plasma therapy – but in the context of COVID-19 treatments and, indeed, treatments for any disease, there must be something more substantive than hype alone.