An international study concluded: convalescent plasma not effective for Covid-19 coronavirus. The authors of this May 22, 2020 study searched the medical literature around the world and in China. They were interested in randomized studies regarding the use of recovery plasma in the treatment of sick Covid-19 coronavirus patients.
They included infections with acute coronavirus, influenza and Ebola virus infections. Based on 1099 unique records they found 6 studies that were eligible to be included. None of these included patients with Covid-19 coronavirus. The researchers analyzed one nonrandomized study of SARS coronavirus patients treated with recovery plasma. It did not provide statistically significant changes in mortality figures.
Pooled data from four randomized studies regarding 572 influenza patients did not show significant differences regarding death rates, length of hospital stay or complete recovery time. Convalescent plasma for treatment of active influenza cases showed no or very few adverse effects.
Other studies regarding Covid-19 coronavirus patients
The above study was flawed. In particular, researchers did not include any Covid-19 coronavirus cases in the study to test whether convalescent plasma is effective against it.
But there are many other smaller studies and clinical observations that showed some effects in shortening the Covid-19 coronavirus infection length and severity.
In a Mayo Clinic supervised study about 20,000 patients have been infused with 15,000 convalescent plasma samples. This study is ongoing.
A prior study from China showed that when physicians treated patients with Covid-19 coronavirus 21 days into shedding the virus, treatment with convalescent serum was only partially effective. It showed that there was earlier seroconversion to a negative Covid-19 test and the patients survived longer. But at the end there was no significant difference with regard to mortality in comparison to a control group.
Cochrane study about convalescent plasma in treating Covid-19 coronavirus patients
Another study reviewed 48 ongoing investigations about treating Covid-19 coronavirus patients with convalescent plasma. The investigators found that a lot of the studies were of poor quality. At this point no definitive results were available about the effectiveness or the side effects of the convalescent plasma. However, as the studies are ongoing, the Cochrane study will be updated when the results of the other studies are available.
Several studies regarding the effects of convalescent plasma on patients with Covid-19 coronavirus infections are available. However, researchers could not confirm effectiveness. With other viral illnesses like hepatitis B and others convalescent plasma is remarkably effective in improving an acute infection. This is why physicians continue to treat patients with Covid-19 coronavirus infections. The dosages of plasma vary between 200 ml and 500 ml per treatment. But physicians also found a big difference whether they treated the illness between day 1 and day 3 or only 3 weeks into the disease. Early treatments and higher plasma amounts seem to be more effective. At this time we need to await the Cochrane study update to get concrete data. This will help to come to a conclusion about the effectiveness of convalescent plasma therapy for Covid-19 coronavirus.