Immune globulin is recommended as a method for preexposure and postexposure prophylaxis of hepatitis A (an alternative is the hepatitis A vaccine). Despite having prescribed immune globulin many times, I had never once specified a proprietary name, nor considered the possibility that some of the preparations I might prescribe may not be effective.
The research letter by Tejada-Strop et al1 demonstrates that there is tremendous heterogeneity in the potency of available immune globulin preparations, with only 2 of 9 products currently on the market meeting the minimal potency standard for hepatitis A. Furthermore, even though these products are meant to provide 90 days of protection (important when used for travel), none of the products provided this; 4 of 9 never reached protective levels of anti–hepatitis A immune globulin; 2 maintained protective levels for only 1 day; and the other 3 maintained protective levels for 19, 40, and 53 days, respectively.
Katz MH. Regulatory Action Necessary for Immune Globulin Preparations for Hepatitis A Prophylaxis. JAMA Intern Med. Published online January 09, 2017. doi:10.1001/jamainternmed.2016.9196