convalescent plasma treatment (n=42) vs. control (n=45)
randomized controlled trial
some concerns about risk of bias
anti-influenza plasma
two units (or paediatric equivalent) of anti-influenza plasma with haemagglutination inhibition antibody titres of 1:80 or more
standard care
infections other than COVID-19
open-label
29 academic medical centres in the USA
IRC005 Study Team, 2019 NCT02572817
convalescent plasma treatment (n=92) vs. placebo (n=48)
randomized controlled trial
low risk of bias
anti-influenza plasma
high-titre anti-influenza plasma (haemagglutination inhibition antibody titre ≥1:80)
low-titre plasma
low-titre plasma (≤1:10)
infections other than COVID-19
double-blind
41 US medical centres
INSIGHT FLU-IVIG (Davey), 2019 NCT02287467
convalescent plasma treatment (n=-9) vs. placebo (n=-9)
randomized controlled trial
some concerns about risk of bias
anti-influenza hyperimmune intravenous immunoglobulin (hIVIG)
standard care plus a single 500-mL infusion of high-titre hIVIG (0·25 g/kg bodyweight, 24·75 g maximum; hIVIG group)
placebo
saline placebo
infections other than COVID-19
double-blind
not in intention to treat
Hung, 2013 NCT01617317
convalescent plasma treatment (n=17) vs. placebo (n=18)
randomized controlled trial
some concerns about risk of bias
hyperimmune IV immunoglobulin treatment
convalescent plasma from patients who recovered from the 2009 pandemic influenza A(H1N1) (A[H1N1]) infection, fractionated to hyperimmune IV immunoglobulin (H-IVIG) by CSL biotherapies (now bioCSL)
placebo
normal IV immunoglobulin manufactured before 2009 as control