Asthma Remission and EGPA With Biologics

VIENNA — Physicians are called to record clinical details of patients with asthma undergoing biologic therapy to monitor clinical remission and keep an eye on eosinophilic granulomatosis with polyangiitis (EGPA) symptoms as patients come off the medications, according to pulmonary experts presenting at the European Respiratory Society (ERS) 2024 International Congress.

Biologics have revolutionized the treatment of severe asthma, significantly improving patient outcomes. However, the focus has recently shifted toward achieving more comprehensive disease control. Remission, already a well-established goal in conditions like rheumatoid arthritis and inflammatory bowel disease, is now being explored in patients with asthma receiving biologics.

Peter Howarth, medical director at Global Medical, Specialty Medicine, GSK, in Brentford, England, told Medscape Medical News that new clinical remission criteria in asthma may be overly rigid and of little use. He said that more attainable limits must be created. Meanwhile, clinicians should collect clinical data more thoroughly.

In parallel, studies have also raised questions about the role of biologics in the emergence of EGPA.

Defining Clinical Remission in Asthma

Last year, a working group, including members from the American Thoracic Society and the American College and Academy of Allergy, Asthma, and Immunology, proposed new guidelines to define clinical remission in asthma. These guidelines extended beyond the typical outcomes of no severe exacerbations, no maintenance oral corticosteroid use, good asthma control, and stable lung function. The additional recommendations included no missed work or school due to asthma, limited use of rescue medication (no more than once a month), and reduced inhaled corticosteroid use to low or medium doses.

To explore the feasibility of achieving these clinical remission outcomes, GSK partnered with the Mayo Clinic for a retrospective analysis of the medical records of 700 patients with asthma undergoing various biologic therapies. The study revealed that essential data for determining clinical remission, such as asthma control and exacerbation records, were inconsistently documented. While some data were recorded, such as maintenance corticosteroid use in 50%-60% of cases, other key measures, like asthma control, were recorded in less than a quarter of the patients.

GSK researchers analyzed available data and found that around 30% of patients on any biologic therapy met three components of remission. Mepolizumab performed better than other corticosteroids, with over 40% of those receiving the drug meeting these criteria. However, when stricter definitions were applied, such as requiring four or more remission components, fewer patients achieved remission — less than 10% for four components, with no patients meeting the full seven-point criteria proposed by the working group.

An ongoing ERS Task Force is now exploring what clinical remission outcomes are practical to achieve, as the current definitions may be too aspirational, said Howarth. “It’s a matter of defying what is practical to achieve because if you can’t achieve it, then it won’t be valuable.”

He also pointed out that biologics are often used for the most severe cases of asthma after other treatments have failed. Evidence suggests that introducing biologics earlier in the disease, before chronic damage occurs, may result in better patient outcomes.

Biologics and EGPA

In a retrospective study, clinical details of 27 patients with adult-onset asthma from 28 countries, all on biologic therapy, were analyzed. The study, a multicounty collaboration, was led by ERS Severe Heterogeneous Asthma Research Collaboration, Patient-centred (SHARP), and aimed to understand the role of biologics in the emergence of EGPA.

The most significant finding presented at the ERS 2024 International Congress was that EGPA was not associated with maintenance corticosteroids; instead, it often emerged when corticosteroid doses were reduced or tapered off. “This might suggest that steroid withdrawal may unmask the underlying disease,” Hitasha Rupani, MD, a consultant respiratory physician at the University Hospital Southampton, in Southampton, England, told Medscape Medical News. Importantly, the rate at which steroids were tapered did not influence the onset of EGPA, indicating that the tapering process, rather than its speed, may be the critical factor. However, due to the small sample size, this remains a hypothesis, Rupani explained.

The study also found that when clinicians had a clinical suspicion of EGPA before starting biologic therapy, the diagnosis was made earlier than in cases without such suspicion. Rupani concluded that this underscores the importance of clinical vigilance and the need to monitor patients closely for EGPA symptoms, especially during corticosteroid tapering.

The study was funded by Merck. Smith reported receiving grant funding from Merck. Jones reported no relevant financial relationships. 

Manuela Callari is a freelance science journalist specializing in human and planetary health. Her words have been published in The Medical Republic, Rare Disease Advisor, The Guardian, MIT Technology Review, and others.