Plasma therapy ineffective in reducing COVID-19 mortality: AIIMS study

August 8, 2020 0 By FM

Convalescent plasma therapy may not be beneficial in reducing mortality risk among COVID-19 patients, according to an interim analysis of a randomised controlled trial done at AIIMS.

The therapy involves taking antibody laden plasma from the blood of a person who has recovered from COVID-19 and transfusing those into an active coronavirus infected patient to help kickstart the immune system to fight back the infection.

No clear mortality benefit of convalescent plasma therapy was seen during a trial conducted among 30 COVID-19 patients, AIIMS Director Dr Randeep Guleria was quoted as saying.

During the trial, one group of patients was given convalescent plasma therapy along with the standard supportive treatment while the other group only received standard treatment. The number of fatalities recorded in both the groups was equal and there was not much clinical improvement in the condition of patients, he said.

The study, however, is just an interim analysis and a more detailed evaluation needs to be done to see if any sub-group might benefit from plasma therapy, Dr Guleria said. He also underlined that plasma has to be tested for its safety and should have sufficient antibody to be useful to COVID-19 patients.
   
Recent studies have shown that plasma therapy may only work effectively when the antibody laden plasma for treatment is retrieved from a recently recovered COVID-19 patient as the antiviral antibodies may persist only for up to 2 to 3 months in recovered individuals.

Plasma must contain a sufficient amount of neutralizing antibody against that infection for plasma therapy to be effective. However, the therapy may also carry risks such as inadvertent transfer of blood-borne infections and reactions to serum constituents, including immunological reactions such as serum sickness, that may worsen the clinical condition.

According to the Clinical Management Protocols for COVID-19 issued by the Union Health Ministry, off-label convalescent plasma may be considered for COVID-19 patients with moderate disease who are not improving, which means oxygen requirement is progressively increasing, despite the use of steroids.

The use of off-label convalescent plasma for treating coronavirus patients in the moderate stage of the illness has been included under “investigational therapies”.

ABO compatibility and cross-matching of the donor plasma is a prerequisite while considering convalescent plasma.

The recipient should be closely monitored for several hours after transfusion for any adverse events and its use should be avoided in patients with immunoglobulin A deficiency or immunoglobulin allergy. The dose is variable ranging from 4 to 13 ml/kg; usually 200 ml single dose given slowly over not less than two hours, according to the Clinical Management Protocol.