Hyperimmune immunoglobulin for people with COVID-19

Area of Science:

• Immunology
• Infectious Diseases
• Clinical Medicine

Background:

• Hyperimmune immunoglobulin (hIVIG) contains polyclonal antibodies derived from convalescent plasma or immunized animals.
• hIVIG is under investigation as a potential therapy for coronavirus disease 2019 (COVID-19).

Purpose of the Study:

• To assess the benefits and harms of hIVIG therapy for COVID-19 patients.
• To maintain an up-to-date evidence base using a living systematic review approach.

Main Methods:

• Systematic review of randomized controlled trials (RCTs) identified through major databases.
• Searches conducted up to March 31, 2022, including WHO, Cochrane, Epistemonikos, Medline, and Embase.
• Risk of bias assessed using RoB 2 and certainty of evidence rated with GRADE.

Main Results:

• Five RCTs (947 participants) evaluated human-derived hIVIG and animal-derived antibodies (equine F(ab')2 fragments).
• Human-derived hIVIG showed little impact on mortality and clinical improvement but may increase severe adverse events (grade 3-4).
• Equine F(ab')2 fragments may reduce mortality and clinical worsening but evidence certainty is low.

Conclusions:

• hIVIG prepared from humans has uncertain benefits for moderate-to-severe COVID-19, with a potential increase in severe adverse events.
• Animal-derived polyclonal antibodies may offer some benefits but require more research, especially considering SARS-CoV-2 variants and vaccination status.
• Evidence for hIVIG in asymptomatic or mild COVID-19 is lacking; this is a living systematic review updated regularly.