NEW DELHI: In a development that may dash the hopes of policymakers, doctors and public alike, the world's largest randomised control trial to assess plasma therapy for Covid-19 has shown that it does not benefit either in reducing mortality or arresting the progression of the disease.
The trial, called PLACID, was carried out under the aegis of Indian Council of Medical Research in 39 hospitals across 14 states and Union Territories.
The study involved 464 moderately ill patients with breathing difficulties and oxygen saturation level of less than 93 %, of whom 235 were given convalescent plasma with antibodies against SARS CoV2 received from donors who had recovered from the virus, while 229 received only standard care.
Those in the intervention group were transfused with two doses of 200 ml plasma 24 hours apart. Both the intervention and control groups were compared after 28 days.
The findings, released now on a preprint server of health research, have shown that 34 patients or 13.6 % who received plasma therapy died while 31 patients or 14.6 % who did not receive it, succumbed to the infection. Also, 17 patients in each group progressed to have severe disease.
“CP was not associated with a reduction in mortality or progression to severe COVID-19,” noted the authors led by ICMR scientist Dr Aparna Mukherjee who led the trial.
These findings assume immense significance as several state governments have actively promoted the therapy and have set up plasma banks after the national Covid-19 clinical management protocol allowed it as an investigational therapy.
There is also a thriving black market for plasma in several parts of the country as kin of the sick scramble to arrange plasma in the hope of saving their loved ones, a fact acknowledged in the study.
Doctors who have been using the therapy, such as Dr Anupam Singh in Ghaziabad, on Covid patients meanwhile called the results “disappointing.”
There was however some minor benefit in terms of alleviation of some symptoms though for those received the therapy. The proportion of patients with resolution of shortness of breath and fatigue at day 7 were higher in the intervention arm, for example, whereas fever and cough resolution were not different in the two groups.
But, total and post-enrolment duration of respiratory support, the proportion of patients requiring invasive ventilation, and proportion of patients requiring vasopressor support were not different between the trial participants in two arms.
“Although the use of CP seemed to improve the resolution of shortness of breath and fatigue, reduce FiO2 (fraction of inspired oxygen) requirement in the first week and led to higher negative conversion of viral RNA, this did not translate into reduction in 28-day mortality or progression to severe disease in moderate Covid19 patients,” noted the study.