Research Examines US Characteristics of Biologic Use for Asthma

Recent research presented at the 2022 American Academy of Allergy, Asthma & Immunology Annual Meeting examined different aspects of the use of biologics for severe asthma.

In one study,¹ investigators examined whether racial/ethnic disparities exist in the prescription of biologics for patients with moderate to severe persistent asthma.

The TriNetX Diamond Network claims database was used to identify patients aged 18 and older with asthma managed with both medium- to high-dose inhaled corticosteroids and long-acting beta-agonists; patients with a history of previous biologic use were excluded.

Patients were grouped by race/ethnicity (White, Black, and Hispanic), and the 3-year incidence of dupilumab or omalizumab as well as agents that act on interleukin 5 (IL-5) were compared among these cohorts after performing 1:1 propensity score matching (PSM) for baseline demographics, comorbid conditions, and systemic corticosteroid use.

After PSM, there were 29,027 patients in the Black and White cohorts. There was no significant difference in the prescription of biologic medications between Black and White patients (0.30% vs 0.40%, P = .37), nor were significant differences seen between dupilumab and omalizumab.

There were 19,418 patients in the Hispanic and White cohorts, and there was no significant difference in the prescription of biologics between these 2 groups (0.41% vs 0.46%, respectively; P = .40).

However, although there were no statistical differences in the dispensing of dupilumab or omalizumab, fewer Hispanic patients were prescribed anti–IL-5 agents compared with White patients: 0.14% vs 0.26% (P = .009).

While the investigators said the report shows that patients with moderate to severe persistent asthma “are receiving optimal add-on biologic care irrespective of race/ethnicity,” they noted that anti–IL-5 therapies are less frequently prescribed to Hispanic patients, for reasons that are not yet known.

In a second abstract,² researchers looked at the US clinical and economic burden of severe asthma across a range of eosinophil levels and disease control status. A retrospective cohort study was conducted using MarketScan health care claims linked to laboratory data. Patients 12 years and older with evidence of severe persistent asthma from March 2017 through September 2019 were included. They were followed through the first date of disenrollment, starting a biologic for asthma, or through the end of 2019.

Researchers assessed asthma treatment, exacerbations, and health resource utilization, both overall and stratified by blood eosinophil count (BEC; cells/mcL) and asthma control status. Asthma control was quantified on the basis of asthma-related hospitalizations, outpatient visits with a corticosteroid prescription fill, and short-acting beta-agonist prescription fills.

The cohort included 88,206 patients with severe asthma (mean age [SD], 48.0 [16.4] years; 60.5% female), of whom 10,407 (11.8%) had a BEC reported (<150: 38.1%; 150-300: 39.7%; >300: 22.2%).

Overall, 42.3% demonstrated uncontrolled/suboptimally controlled asthma during follow-up, and the 1-year cumulative incidence of asthma exacerbations was 24.2%. Among those with BEC reported, these estimates were 26.7% (<150), 26.4% (150-300), and 28.9% (>300).

Further, mean annual total health care costs were $16,575 (all-cause) and $3720 (asthma-related). Perhaps not surprisingly, costs increased as asthma control decreased; mean asthma-related cost was more than 2 times higher in uncontrolled vs controlled patients, the investigators wrote.

Among those with BEC reported, these estimates were $20,392 (all-cause) and $3975 (asthma-related) and were generally similar across BEC levels.


“The US burden of severe asthma untreated with biologics is significant for patients with or without an eosinophilic phenotype and is inversely related to level of disease control,” the researchers concluded.

References

1. Kaminsky L, Al-Shaikhly T. Racial and ethnic disparities in biologic prescriptions for moderate-to-severe persistent asthma. Presented at: 2022 American Academy of Allergy, Asthma & Immunology Annual Meeting; February 25-28, 2022; Phoenix, Arizona. Abstract 455.

2. Jo H, Desai P, Llanos Ackert JP, et al. Clinical and economic burden of patients with severe asthma untreated with a biologic in the United States, overall and by blood eosinophil and level of asthma control. Presented at: 2022 American Academy of Allergy, Asthma & Immunology (AAAAI) Annual Meeting; February 25-28, 2022; Phoenix, Arizona. Abstract 053.