Delhi chief minister Arvind Kejriwal on Friday signalled his government’s intent to provide convalescent plasma therapy -– an experimental treatment -– to all serious Covid-19 patients if encouraging observations on four patients are seen two or three more patients.

Four Covid-19 patients at the Lok Nayak Jaiprakash Narain Hospital in Delhi who had received the plasma therapy have recovered, the state government said in a media release. Convalescent plasma that contains antibodies to the virus that causes Covid-19 is under assessment for its efficacy as Covid-19 treatment.

“We have tried the therapy on four patients and the results are satisfactory,” Kejriwal said in the release. “We’ve got permission for limited trials. After trials on two or three more patients, we will apply for permission for the plasma therapy to be given to serious corona patients across Delhi,” he said.

Kejriwal cautioned that these are initial results and plasma therapy should not yet be viewed as a treatment.

The Indian Council of Medical Research has received 99 applications from research groups across the country for a randomised controlled study to assess the safety and efficacy of convalescent plasma therapy in Covid-19 patients.

The use of convalescent plasma has been studied in outbreaks of other infections including the 2003 severe acute respiratory virus epidemic, the 2009-2019 H1N1 influenza virus pandemic, and the 2012 middle-eastern respiratory syndrome epidemic.

“Although promising, convalescent plasma has not yet been shown to be safe and effective as a treatment for Covid-19,” the US Food and Drug Administration had said on April 13. It is important to study the safety and efficacy of Covid-19 convalescent plasma in clinical trials.”

A senior doctor in a Delhi government hospital said the goal of plasma therapy would be block the progression of Covid-19 into a serious third stage.

“This viral infection has three stages -– first the virus enters the body, second it affects the lungs, the third stage is when the body releases cytokines to kill the virus. The third stage involves high risk as it can lead to organ failure,” said Shiv Kumar Sarin, director of the Delhi government’s Institute of Liver and Biliary Sciences.

“If a person is treated with plasma therapy in the second stage, we can neutralize the virus and prevent organ failure. We treat a person who is in the second stage and has not reached the third stage.”

The plasma is extracted from the blood of patients who have recovered from Covid-19. Sarin said patients who have recovered from the infection would be encouraged to donate their plasma. “Plasma therapy is also inexpensive,” he said. Two or three more patients at LNJP hospital will be provided plasma therapy.