Insufficient evidence for use of convalescent plasma in COVID-19 patients

Convalescent plasma (CP) treatment is one treatment option currently being investigated in COVID-19.

Our review of evidence for a living systematic benefit-risk assessment of the use of convalescent plasma for COVID-19 patients is complete and has been submitted for publication. Our research team found that based on currently available data, there is insufficient evidence to support the use of convalescent plasma compared to standard of care in severe COVID-19 disease.

Our systematic benefit risk assessment is based on currently available data and provides a framework inclusive of key benefits and risks for convalescent plasma in severe COVID-19 disease. This semi-quantitative method is based on the Benefit-Risk Action Team (BRAT) framework.

The study team screened 523 papers and found that four papers were eligible for inclusion because they compared use of convalescent plasma to standard of care, placebo or other treatments. One study showed a slightly better ‘time to clinical improvement’ from 2.15 days down to 0.99 days, but this was not statistically significant and the study may have been underpowered. Analysis of the three other papers showed they were limited by small patient numbers, lack of randomisation, and lack of clarity because of the co-administration of other treatments. 

The lack of evidence from controlled studies meant that it was not possible to complete a data summary table and the further quantitative analysis required to reach a benefit-risk conclusion.

Due to the dynamic nature of this benefit-risk assessment method, additional clinical trial data can be incorporated into the framework when data that may have an impact on the benefit- risk becomes available, to provide an updated benefit-risk assessment.

The preprint is available here: https://doi.org/10.1101/2020.08.24.20180729