Convalescent plasma doesn’t stop COVID deaths or severity: ICMR study in BMJ

Aditi Tandon

Tribune News Service

New Delhi, October 23

The enthusiasm around the protein-rich convalescent plasma, generated in the earlier days of the COVID-19 pandemic, has been shattered with a path-breaking study by Indian researchers published on Friday in the reputed British medical journal showing that the therapy neither prevents deaths nor progression of moderate disease to severe.

The excitement around plasma therapy stemmed from its 100-year history of use in the treatment of other infectious diseases, including influenza and Ebola, and rapid availability from voluntary donors.

However, experts from the Indian Council of Medical Research (ICMR), in this latest study on 464 adults across 39 hospitals, have shown that “convalescent plasma was not associated with a reduction in progression to severe COVID-19 or mortality over 28 days since patient enrolment”.

Researchers actually found that progression to severe disease or death mortality at 28 days happened more in moderate COVID-19 patients who received plasma than those who received standard care.

Disease severity or mortality after enrolment occurred in 44 (19 per cent) participants in the intervention arm (those who got plasma) and 41 (18 per cent) in the control arm.

The study titled “Convalescent plasma in the management of moderate COVID-19 in adults in India: Open-label phase II multicentre randomised controlled trial (PLACID Trial)”, published in BMJ today, meant to investigate the effectiveness of using convalescent plasma to treat moderate coronavirus disease 2019 (COVID-19) in adults in India.

Participants in the intervention arm received two doses of 200 ml convalescent plasma, transfused 24 hours apart. The other arm received normal care without plasma.

A higher proportion of patients in the intervention arm, however, showed resolution of shortness of breath and fatigue at day 7, whereas the resolution of fever and cough did not differ between the two arms.

Several state governments, including Delhi, had gone all out to set up plasma banks for the treatment of COVID patients, who are now shown not to have benefitted from the therapy, which was allowed in the Indian COVID protocol.

Government is now working to delete its approval.

The WHO Solidarity Trials have earlier already shown the inefficacy of other repurposed drugs to reduce the severity of disease in COVID patients, including Remdesivir and the combination of anti-viral drugs Lopinavir and Ritonavir.

Why plasma?

In the pre-vaccine era, convalescent plasma was used to treat viral diseases such as poliomyelitis, measles, mumps and influenza, and more recently, influenza, Ebola virus disease and severe acute respiratory syndrome as in the case of coronavirus, with varying degrees of success.

Evidence suggests that convalescent plasma collected from survivors of COVID-19 contains receptor binding domain-specific antibodies with potent antiviral activity. So far, only two randomised controlled trials on convalescent plasma use in COVID-19 have been published — one from China and the other from the Netherlands.

Both were stopped prematurely.

The Indian ICMR trial is, therefore, the largest randomised trial to have been completed with results published in the BMJ today.