The Indian Council of Medical Research (ICMR), whose study had earlier found Convalescent Plasma Therapy (CPT) is not effective in arresting disease progression or mortality, has surprised many by coming out with an advisory on the use of plasma therapy, but some experts think the conditions specified in the document are good enough to restrict its use, if implemented properly.

There are others who have welcomed the ICMR decision vouching for its effectiveness in certain patients.

Protocol

The advisory said medical institutions that are using CPT for Covid-19 management should ensure that certain criteria are met for its use. Besides insisting on the presence of certain level of general antibodies or neutralising antibodies in donor plasma and absence of antibodies in the recipient, it stipulates at what stage of disease the procedure can be administered.

ICMR’s directive has come two days after a high level meeting chaired by Home Minister Amit Shah directed an expert team including ICMR DG Balram Bhargava, to develop a protocol for plasma therapy, whose indiscriminate use had become a serious worry.

“There are three different criteria for measuring antibody titres mentioned in the document. Only a handful of healthcare facilities in the country can actually conduct two such tests — measuring IgG (immunoglobulin) concentration as well as neutralising antibody concentration in donor plasma, while the third — an immunoassay technique called CLIA — is more prevalent in big hospitals and pathlabs,” said a medical scientist, who was part of the earlier ICMR study on CPT, which published in British Medical Journal recently.

The scientist, who didn’t want to be named, said the other two conditions will restrict the number of patients who can receive plasma therapy substantially. For instance, the ICMR directive discourages plasma therapy in patients who have already developed antibodies. The ICMR’s own randomised controlled trials carried out in 464 patients found that 83 per cent of the patients participated in the study have own antibodies when they were administered CPT.

Thirdly, the advisory also insists that it should be given at early days of the infection (ideally between 3 to 7 days), but most patients reach hospitals only around 5th or 6th day of the infection, squeezing the window available substantially, the scientist said.

On the other hand, Dipyaman Ganguly, a senior scientist at the Kolkata-based Indian Institute of Chemical Biology, a constituent laboratory of the Council of Scientific and Industrial Research, who has been studying plasma therapy, said: “I am happy that now ICMR is allowing it.”

Ganguly, who refused to talk about findings from his study which is about to be wrapped up, vouched by CPT and said the general clinical experience out of off-label usage has been that there are people who are actually benefitted from it, though it doesn’t work in all.

“What is seen is that the type of plasma given (in terms of antibody content), time of giving the therapy and what kind of patients getting it would determine whether it works or not,” said Ganguly, whose team is trying to stratify who would benefit from it and who would not. The final report of their study is expected to ready soon.