Systematic review of immunosuppressant guidelines in the COVID-19 pandemic.

Clinical practice guidelines on taking immunosuppressants during the COVID-19 outbreak vary in quality. The level of evidence informing the available guidelines was generally low. Given the novel nature of COVID-19, the guidelines draw on existing knowledge and data, refer to the use of immunosuppressants and risks of serious infections of other aetiologies and have extrapolated these to form their evidence base.