Anti-interleukin 5 therapies failure criteria in severe asthma: a Delphi-consensus study

Initiation, response assessment, and switch of antibody therapies in patients with severe asthma - A survey among German specialists

Background

For therapy of severe asthma 5 monoclonal antibodies have been available in Germany up to November 2022, but no clear rules exist on choice of initial therapy, assessment of response, and switch.

Objective

To assess current practice on all aspects of biologic therapy by specialists in Germany.

Methods

A questionnaire was created by specialists for severe asthma, which was tested and modified by further experts. We invited 119 pulmonologists of the German Asthma Net (GAN) to complete the survey and used SoSci Survey and SPSS for data collection and analysis.

Results

Forty-seven pulmonologists took part in the survey with a median annual number of patients treated with biologics of 35, 55% worked in an outpatient practice, and 40% in a hospital. Exacerbations and oral steroid use were the most important factors for the decision to start a biologic therapy. Accordingly, these parameters were also the most relevant for assessment of response. Most participants considered type-2 inflammation biomarkers and comorbidities (foremost CRSwNP and AD) for choosing initial biologic. Asthma Control Test (ACT) was the most common instrument for assessing status of disease control. There was no consensus on thresholds for response of pulmonary function tests including FEV1, FVC, and RV. Eighty-five percent of participants distinguished between "responders", "partial responders" and "non-responders". Comorbidities played an important role for the decision to switch to another biologic, eg, when initial therapy had insufficient effectiveness on CRSwNP.

Conclusion

This study provides a detailed insight into current opinions and practice of biologic use in severe asthma in Germany.

Overall Response to Anti-IL-5/Anti-IL5-Rα Treatment in Severe Asthma Does Not Depend on Initial Bronchodilator Responsiveness

BACKGROUND

Positive bronchodilator responsiveness (BDR) (change in forced expiratory volume in 1 second [ΔFEV₁] ≥ +200 mL and ≥ +12%) after inhalation of a short-acting beta-2 agonist has been an inclusion criterion in licensing trials of anti-interleukin 5/anti-interleukin 5 receptor alpha (anti-IL-5/anti-IL-5Rα) biologics in severe asthma. However, in clinical practice, patients with severe uncontrolled asthma frequently show a negative BDR.

OBJECTIVE

To investigate whether the response to anti-IL5/anti-IL5Rα therapies differs between patients with positive and negative BDR at baseline.

METHODS

Retrospective multicenter analysis of treatment outcomes in patients with severe asthma receiving anti-IL-5/anti-IL-5Rα stratified for baseline BDR.

RESULTS

Of 133 patients included, 37 had a positive and 96 had a negative BDR at baseline. Following anti-IL-5/anti-IL-5Rα treatment, FEV₁ improved significantly in both groups compared with baseline (P < .0001), with no significant difference between patients with positive and negative BDR (ΔFEV₁ +493 mL vs +306 mL; P = .06). Forced vital capacity (FVC) increased (ΔFVC: +85 mL vs +650 mL; P < .01) and residual volume (RV) decreased (ΔRV +113 mL vs -307 mL; P < .01) significantly in patients with negative BDR. Median annualized exacerbations (0 vs 0; P = .7), reduction of exacerbation rate (Δexacerbations 0 vs -2; P = .07), continuous oral corticosteroids (OCS) use (Δpatients on OCS -35% vs -39%; P = .99) and improvement of Asthma Control Test (ACT) score (ΔACT 6 vs 5; P = .7) were similar in both groups. Multivariate logistic regression analysis showed no significant correlations of positive versus negative BDR with response parameters.

CONCLUSIONS

Both groups improved following treatment with similar responses concerning reduction of OCS therapy, exacerbations, and improvement of symptom control. Pulmonary function also improved in both groups during anti-IL-5/anti-IL-5Rα treatment, with differences in response patterns noted.