Use of long-acting muscarinic antagonists for severe asthma: insights from clinicians in the SHARP network

Background: There is limited real-world evidence on the use and positioning of inhaled long-acting muscarinic antagonists (LAMAs) for treating severe asthma. Objective: We aimed to assess the differences in clinicians' perspectives on prescribing LAMA for severe asthma across Europe. Methods: Within the Severe Heterogeneous Asthma Research collaboration, Patient-centred (SHARP) network, we conducted a multi-country survey of 470 respiratory clinicians in 2023-24. Results: Most participants were pneumonologists (83%). 68% reported using specific criteria for prescribing LAMA for severe asthma, primarily fixed bronchial obstruction (68%), frequent asthma exacerbations (65%), and a history of smoking (53%). Improved quality of life, lung function improvement, and reduction of asthma exacerbations were the three expected outcomes of LAMA treatment that showed the largest agreement across clinicians (85-95%). As compared to non-severe asthma specialists (about 50% of the sample), severe asthma specialists were more likely to report always prescribing LAMA before biologics (54 vs. 41%) and before oral corticosteroids (OCS) (51 vs. 40%). Approximately 90% of participants prioritised tapering or discontinuing OCS before stopping LAMA. Overall, participants in Northern (n = 73) and Western Europe (n = 71) appeared less prone to prescribe LAMA and less confident in their benefits compared to those from Eastern (n = 88) and Southern Europe (n = 238). In particular, most participants from Latvia (91%) and Lithuania (67%) reported that LAMAs are not reimbursed for severe asthma in their countries. Most participants who expressed their opinion favoured triple therapy (n = 236) over single inhaler therapy (n = 91). Conclusion: Our findings show that barriers and heterogeneous approaches still limit LAMA prescription for severe asthma in Europe, potentially leading to the underuse of this treatment option. Establishing a clear role for LAMA within a precision medicine framework is crucial; this aspect is not yet firmly supported by current international recommendations.