Reply to high cost of immunoglobulin replacement therapy: Causes and implications

The goal of the immunoglobulin (IG) stewardship Perspective,1 which began with the dictionary definition of stewardship, was to encourage allergist/immunologists to use IG appropriately, not to reduce costs nor to open a discussion of pharmaceutical pricing. Nevertheless, Sun and Romberg2 use the Perspective to attack the cost of immunoglobulin products sold in the United States3 and advocate for value-based pricing of IG. Although value-based pricing has virtues,4 its application to rare diseases such as inborn errors of immunity has been well refuted.