Cost-Effectiveness, Impact of AIT on Costs Among Published AAAAI Research

Is it cost-effective to prescribe epinephrine to every patient on allergen immunotherapy (AIT)? Does AIT have an impact on healthcare costs? These and other issues were included among the research prepared and published for the American Academy of Allergy, Asthma & Immunology 2020 Annual Meeting.

Universal Self-injectable Epinephrine Cost-Effective for Some on AIT

Self-injectable epinephrine (SIE) is commonly prescribed patients taking allergen immunotherapy (AIT) because of anaphylaxis risk. To determine the cost-effectiveness of universally prescribing SIE to all patients on AIT, researchers constructed a Markov model over an 80-year time horizon from both societal and healthcare perspectives.

Researchers found prescribing SIE only to individuals at higher risk for prior systemic reaction to immunotherapy (SRIT) is highly cost-effective compared with universally prescribing SIE. The findings indicate a contextualized approach that offers SIE only to those with prior systemic reaction to immunotherapy (SRIT) may be superior to a blanket approach.

In the model, researchers devised a base-case scenario of a 5-year-old child with allergic rhinitis who receives 5 years of AIT under a universal SIE approach. This was compared to the approach of prescribing SIE after an initial SRIT.

To determine the incremental cost-effectiveness ratio (ICER) in 2019 US dollars (USD) per quality-adjusted life year (QALY) gained, researchers conducted a cohort analysis and microsimulations.

Specifically, the model illustrated universal SIE compared with SIE after the first SRIT is not cost-effective, resulting in an ICER of $669,327,730 per QALY gained. The microsimulation (n = 10,000) illustrated that a contextualized prescribing approach for SIE yielded lower costs ($16,232 [$5204] vs. $19,653 [$4297]). In addition, the contextualized approach was more effective than the universal approach, resulting in 25.58 QALY compared with 25.56 QALY.

However, the universal approach did become more cost effective when SIE cost $24 per twin pack and offered 1000x protection against a death from AIT. In addition, AIT fatality rates also needed to be magnified to 2.7 per 10,000 patients for the universal approach to be cost effective.

Claims Analysis of Patients With Allergic Rhinitis Highlights Benefit of AIT

Another abstract conducted a claims analysis of patients with allergic rhinitis (AR) in order to assess the real-world evidence linking AIT patterns, clinical characteristics, and healthcare costs in the United States.

Patients with AR were identified via IBM MarketScan databases between 2014 and 2017. Current procedural terminology and national drug codes (earliest AIT claim for vaccine = index date) were used to identify patients who received AIT. Non-AIT patients were identified based on if their claims contained a diagnosis code for AR (earliest AR claim = index date). In addition, AIT patients were separated into adherence groups (1 claim [early discontinuers] vs. 6+ claims [persistent]) and assessed for comorbidities, demographic characteristics, and healthcare costs.

The study included a total of 2,461,877 patients with AR (16,377: 1 AIT claim; 76,198: 6+ claims; 2,369,302 non-AIT). Researchers found that patients with 6 or more AIT claims had significantly higher rates of comorbid conditions that patients with 1 AIT and no AIT claims. This included asthma (30.7% vs. 20.6% and 6.7%), upper respiratory tract infections (64.6% vs. 52.4% and 35.8%), and conjunctivitis (24.1% vs. 12.2% and 4.1%; P < .001).

However, patients with 6+ AIT claims did have lower healthcare costs than patients with 1 AIT claim ($11,672 vs. $12,464; P < .001). The majority of patients included in the study were female (60%) and mean patient age was in the mid-30s.

Researchers concluded patients with the highest need for AIT (those with higher allergy-related comorbidities) exhibited the highest rates of medication persistence. The increased use did not result in increased healthcare expenditures, demonstrates an economic benefit of AIT for patients’ management of AR.

The Economic Impact of Food Allergy (FA) in Canada

An additional abstract examined the economic impact of food allergy (FA) in Canada, as no data currently exist on the subject for that country, the researchers said. Individuals, recruited from a nationwide FA registry and FA associations, completed electronic surveys, self-reporting a convincing history or physician diagnosis of FA. The survey included questions on healthcare utilization over the past year relating to FA.

In total, 2536 patients completed the survey between May 2018 and July 2019. Respondents were segmented by those who reported a convincing history of food allergy (2064; 81.4%) and those diagnosed by a physician (472).

Among the 2064 respondents with a convincing history:

• 876 (42.4%) had ever experienced a severe reaction
• 1188 had ever experienced a mild/moderate reaction
• 1148/2064 (55.6%) had a reaction in the preceding year

When the severe cohort was compared with the mild/moderate cohort, the percentage of respondents with more than 1 visit to a physician (75.0% vs 67.9%; 95% CI), or the ER (or the ER (29.7% vs 13.8%; 95% CI) was greater in the severe cohort. In addition, the percentage with more than one hospitalization ((4.6% vs 2.0%), using allergy-related medication (76.8% versus 60.3%) or purchasing auto-injectors (87.7% versus 81.2%) was greater in the severe. For individuals with more than 1 visit, the mean physician visits and ER visits were also greater in the severe cohort.

These findings led researchers to conclude that the economic burden of FA in Canada is substantial, particularly in those with a severe reaction.