Scientists now believe that giving hospitalized Covid patients plasma transfusions of virus survivors could reduce their chance of death.
Medics had hoped infusions of convalescent plasma — a straw-coloured fluid in the blood that contains antibodies — could help the infected recover.
A series of researches showed that the treatment doesn’t increase survival rates. Therefore, the World Health Organization recommends it be only used in the most severe cases.
New York researchers have discovered that patients treated with this therapy are 15% less likely to succumb within the first four weeks.
The team stated that patients most at risk of the coronavirus such as people with diabetes and heart disease benefitted more from treatment.
These experts reviewed eight previous studies that included more than 2000 Covid patients.
These researchers argued that the older clinical trials did not show any effect, even though the drug has been around for more than a century.
Professor Andrea Troxel, study leader and a biostatistician at NYU Langone Health, said: ‘Our results show, overall, patients hospitalised with Covid may derive modest benefit from convalescent plasma.
“Patients who have co-existing diseases were more likely to see improvement in convalescent plasma. This is probably due to the difficulty they have producing antibodies that will fight off their infection.
The plasma is infused to boost the immune system’s response to the virus. However, it can only be used in an early stage before they become too sick.
After scientists found no evidence that convalescent plasma was effective in treating moderately-ill patients, the UK stopped testing it as part of a Covid therapy.
However, the US hospitalized patients with suppressed immune systems are eligible for treatment.
Convalescent plasma (pictured) — the main component of blood that contains antibodies and other immune cells needed to fight the infection — taken from Covid survivors may cut the risk of patients dying, NYU researchers said
NYU researchers examined data from eight different studies — completed in the US, Belgium, Brazil, India, Spain and the Netherlands — to assess how effective the treatment was.
These studies involved 2,341 patients with Covid who had been hospitalized and received an injection of plasma. They were on average 60 years old.
Plasma makes up 55 percent of the blood and is rich in antibodies.
Researchers found that patients who received the treatment within one month of being admitted were 15% less likely to die than those who didn’t receive it, or those who were administered a placebo transfusion.
Published in JAMA Network Open this study contradicts previous findings that therapy was either ineffective or limited.
Imperial College London last year halted their trial of the treatment after data on nearly 1,000 patients showed ‘no evidence’ convalescent plasma boosted survival rates.
Oxford University researchers followed their lead last year after an analysis of 1 800 deaths from 10,400 patients revealed that it did not make a significant difference.
Following this, doctors were advised by the WHO to limit treatment to severe or critical patients only in clinical trials.
This agency reviewed 16 studies that included more than 16,000 patients and concluded that it does not increase survival rates or decrease the chance of the patient needing to be ventilated. The treatment is expensive and takes a lot of time to perform.
It did say that critically ill patients could benefit, and so it is important to continue clinical trials.
Troxel explained that the advantages of treatment are shown by combining results from several studies. The other studies had too few patients to be able to determine if it affected sub-sets.
Mila Ortigoza (study investigator) stated that plasma taken from infected donors and later vaccinated would be rich in antibodies which could prevent future viruses.
She stated that convalescent plasma could offer a faster, more reliable treatment for Covid’s variants.
Co-investigator of the study, Professor Eve Petkova is a university expert in population health. She said that the group will use the results to develop a scoring system for doctors to determine who receives the most benefit from treatment.