Immunotherapy is the only treatment for allergy to alter the disease course. Limited data exist on direct and indirect costs of subcutaneous (SCIT) and sublingual (SLIT) immunotherapy in America. This article assesses the cost effectiveness worldwide of the two immunotherapies. The risk of systemic allergic reactions to SLIT is low, although case reports of anaphylaxis exist. The first dose is given under specialist supervision, followed by home administration.
Of note, in America multiple allergens are administered per SCIT course compared to Europe.
Only one American study evaluated SLIT versus SCIT costs. SLIT was on average $500-1200 per year (for less than 10 allergens). Authors concluded SLIT was more affordable than SCIT when taking indirect costs into account. A Canadian study suggested the most cost effective option was Oralair (a type of SLIT given for six months per year for 2-3 years). It cost $2471 for the first year of treatment; $948 less expensive than year-round or SCIT administered seasonally. Grazax (another SLIT given for 12 months per year for three years) was also less expensive than year-round SCIT, but more expensive than seasonal SCIT. Findings were similar in a German study. A UK cost evaluation of SCIT (Alutard SQ) and SLIT (Grazax) was based on the assumption that clinical improvement achieved during three years of SCIT or SLIT is maintained for another three years after cessation. SLIT was estimated to require 13 clinic visits per year compared to 46 for SCIT. SLIT resulted in an overall cost reduction of £2869, compared to SCIT. In summary, the cost of immunotherapy in America is a complex topic. Few cost comparisons exist in the literature. The authors suggest that costs of SLIT may be more contained if the number of antigens administered per patient are more carefully selected.
