Mixed-methods evaluation of an enhanced asthma biologics clinical pathway in the West Midlands UK

Biologic treatments can alleviate severe asthma symptoms and reduce health service use. However, service capacity limits and low referral rates from primary care indicate unmet patient need. We report a mixed-methods evaluation of an enhanced severe asthma pathway implemented in Staffordshire and Stoke-on-Trent, UK which aimed to optimise primary care referrals through training/education, and increased capacity in specialist clinics. Quantitative analysis assessed patient wait times between pathway stages, prescribing changes, exacerbations, hospital admissions and asthma control. Interviews with 12 stakeholders evaluated perceptions of the enhanced pathway across settings. In 12 months, 564 patients from 28 general practices were reviewed for biologics eligibility, of whom 125 (22.2%) were referred for specialist assessment. Wait times were significantly lower under the enhanced pathway when compared against historic patients following the standard pathway, and reduced overall from a mean of 76.4 to 26.7 weeks between referral and biologics initiation (p < 0.001). Patients commencing biologics (n = 46) showed significantly reduced reliever inhaler prescribing rates (p = 0.037), 60% lower oral steroid use (p < 0.001), significantly reduced exacerbation rates (p < 0.001) and fewer hospital admissions (p < 0.001) compared with the 12 months pre-treatment. Mean asthma control scores reduced from 3.13 pre-initiation to 1.89 post-initiation (p < 0.001) - a clinically significant improvement. Interviewees viewed the enhanced pathway positively, although ongoing issues related to difficulties engaging primary care amid concerns around increased workloads and pathway capacity. The large number of referrals generated from a comparatively small number of general practices confirms substantial unmet need that an enhanced severe asthma pathway could help address if implemented routinely.