The cost-effectiveness of requiring universal vs contextual self-injectable epinephrine autoinjector for allergen immunotherapy

Background: Aeroallergen immunotherapy (AIT) is a safe and effective disease-modifying treatment associated with rare therapy-associated fatality. Significant practice variation surrounds universal or contextual prescription of self-injectable epinephrine (SIE) for patients receiving AIT.

Objective: To characterize the cost-effectiveness of a universal vs contextual SIE requirement for patients receiving AIT.

Methods: An economic evaluation using cohort and microsimulation was performed from both the societal and health care sector perspectives for patients undergoing AIT, assessing a universal requirement to fill SIE prescriptions at the outset of therapy compared with requiring this only after a systemic reaction to immunotherapy (SRIT).

Results: A universal SIE requirement for AIT is not cost-effective, with the incremental cost-effectiveness ratio for this strategy estimated at $669,327,730 per quality-adjusted life-year (QALY). In the microsimulation (n = 10,000), the mean (SD) costs of a universal approach exceeded that of a more context-specific strategy where SIE was only prescribed for patients after an initial SRIT ($19,653.36 [$4296.66] vs $16,232.14 [$5204.32]), and given the effects on rates of AIT discontinuation, the universal approach was less effective (mean [SD], 25.555 [2.285] QALYs) compared with a contextualized approach (mean [SD], 25.579 [2.345] QALYs). Universal SIE prescription could be cost-effective if it provided a 1000 times protection against AIT fatality at a value-based cost of $24, and the annual AIT fatality rates unrealistically exceed 2.6 per 10,000 patients.

Conclusion: In a simulation of potential SIE-prescribing strategies for patients receiving AIT, a universal approach to an epinephrine autoinjector requirement was not cost-effective when compared with an approach in which an SIE is prescribed only to patients with prior SRIT.