The Role of Bronchial Biopsy in the Prediction of Response to Biologic Therapy in Severe Uncontrolled Asthma: A Prospective Study.

Abstract

Up to two-thirds of patients with severe uncontrolled asthma (SUA) who received biologic therapy do not have a complete response. Can bronchial biopsy (BB) play a role in the identification of patients with SUA who have a better response to biologic therapy? This prospective multicenter study included consecutive patients with SUA who were candidates for biologic therapy. They underwent bronchoscopy and BB prior to biologic therapy, and clinical response was evaluated 6 months later. BB was evaluated according to a previously validated pathological score (PS) and was compared with a score of type 2 (T2) inflammation (T2 score) that includes blood eosinophil count and fractional exhaled nitric oxide in predicting response to biologic therapy. Response was graded as super-response, good response, and partial/no response according to a composite score that includes exacerbations, oral corticosteroid steroid (OCS) use, asthma control test, and improvement in FEV₁. A total of 92 patients were recruited. Of the 92 patients recruited, 78 completed the study. Among them, 63 received an anti-IL-5 or IL-5 receptor (anti-IL5/5R) (mepolizumab, reslizumab, and benralizumab) while 15 received dupilumab. The proportion of super-responders was 36.5% in the anti-IL5/5R group and 26.6% in the dupilumab group (P = .126). The PS was the only variable independently associated with response; the T2 score was not. Super-responders had a statistically significantly higher PS. Response was better predicted by the PS compared with the T2 score in those receiving OCSs and especially in those taking anti-IL5/5Rs. Reduced eosinophil levels (< 10 eosinophils/field) were associated with poor response to biologic therapy. Our findings indicate that BB is more precise in the prediction of response to biologic therapy than the T2 score, especially in those requiring OCSs or receiving anti-IL5/5Rs. Tissue eosinophilia is the main driver of this predictive capacity. However, other items in the PS related to bronchial remodeling might contribute to the identification of response to biologic therapy.