Convalescent plasma not a proven treatment for COVID-19, say medical experts

Findings from many medical trials report that convalescent plasma doesn’t show any benefit over other therapies as far as reducing COVID-19 deaths or duration of hospitalisation.
Man lying on hospital bed, nurse in blue next to him hanging a bag of plasm
Man lying on hospital bed, nurse in blue next to him hanging a bag of plasm

As the country battles a second wave of the COVID-19 pandemic caused by the SARS-CoV-2 virus, hospitals are inundated with patients. As medical professionals are working round the clock trying to save lives, social media and Whatsapp groups are flooded with messages from people desperately trying to find medical oxygen, medicines etc to  save their loved ones. Many even try to source convalescent plasma to treat COVID-19 patients and donation drives are being frantically organised. This, while most medical experts reiterate that plasma therapy has a very limited role in treating COVID-19 patients. Moreover, even the ICMR found that plasma therapy was not effective in reducing mortality in COVID-19 patients and warned against the indiscriminate use of convalescent plasma as a treatment.

What is plasma therapy and how does it work?

“Convalescent plasma therapy is a method where plasma is obtained from individuals who have recovered from an infection and have generated an immune response against the infecting pathogen,” says Dr Rajavardhan R Consultant Intensivist at Manipal Hospital, Whitefield, in Bengaluru. “The logic behind plasma therapy in COVID-19 is that the neutralising antibodies present in the donor plasma will provide passive immunity to the patient by acting on the virus.” 

But, there are some important factors to keep in mind when going in for plasma therapy– such as how far along the patient who has COVID-19 is, whether they have any antibodies and the level of antibodies present in the donated plasma. “Plasma therapy should be administered early and donor plasma should have adequate antibody titre. This can be quantified by using lab assays,” Dr Rajavardhan tells TNM.

When it comes to COVID-19, for a patient in the early stages where active viral replication is ongoing then plasma therapy could be helpful. And antibodies present in the plasma may act against the virus. But, after 7-10 days most of the patients with COVID-19 will have an immune response with good antibody levels. “It is the body's inflammatory response to the virus than the virus itself, which will affect the organs. Hence, if the patient is having moderate to severe disease, and already on a ventilator or if more than 7-10 days have passed, plasma therapy will not show any benefit,” says Dr Rajavardhan.

This is echoed by Dr N Sridhar, Consultant Intensivist Head- Critical Care, Kauvery Hospital, Chennai. Speaking to TNM, he says, “Plasma may or may not work, if it is to work it has to be given very early. But if given very early the patient is not very sick.”

No proven treatment for COVID-19

It is important to remember, say the doctors that TNM spoke to, that there is no 100% effective medicine or proven treatment to cure a patient with COVID-19. Since the disease has only been known for the past year-and-a-half, a lot of treatments are still experimental. “We have not used  plasma treatment for the past 2-3 months,” says Dr P Vasanthamani, Dean of the Kilpauk Medical College (KMC) in Chennai. “We were initially using it but found it didn’t reduce the severity of the disease.” 

She also adds that according to the World Health Organisation and Indian Council of Medical Research (ICMR) guidelines convalescent plasma therapy has a very limited scope in treating COVID-19 patients. In fact, in a number of medical trials done around the world, it was found that convalescent plasma doesn’t show any benefit over other therapies as far as reducing death from COVID-19, duration of hospitalisation, or duration of mechanical ventilation. “One study done in our backyard by ICMR-PLACID Trial in moderate COVID-19 found that it does not reduce progression or reduce mortality,” says Dr Rajavardhan.

Why then are so many people trying to source convalescent plasma and pinning their hopes on it.  Dr Sridhar says, “I have never prescribed plasma for any of my patients, I have done it on one or two occasions where family members have strongly insisted and wanted plasma therapy to be given and arranged the plasma themselves. I have never told anybody, even the sickest ones in the ICU that we should try to give plasma as a last resort.”

Oftentimes, families of patients want to try it as an option when nothing else seems to work. And it is administered on compassionate grounds. But Dr Sridhar says, “You don’t have to run around trying to source plasma nor feel guilty if you aren’t able to source it.”

The doctors, TNM spoke to, say that for a patient having a severe case of COVID-19 or if they are on ventilator, plasma therapy will not work. “Still, we see a lot of families requesting plasma therapy for patients who are having severe COVID-19 or are already on a ventilator,” says Dr Rajavardhan. “And while we find people on social media asking for plasma donations as the last ray of hope, they should understand that there is no magic bullet that will cure COVID-19.” 

Related Stories

No stories found.
The News Minute