AstraZeneca’s anti-interleukin-13 (anti-IL-13) human monoclonal antibody (mAb) tralokinumab failed to meet its primary endpoint of reducing the annual asthma exacerbation rate (AAER) in the first of two pivotal Phase III studies in patients with severe, uncontrolled asthma. The firm said that a planned analysis of STRATOS 1 data did show clinically relevant AAER reductions in a subgroup of patients with elevated biomarker associated with increased IL-13 activity.
This patient subpopulation will now be the focus of analysis for the second Phase III study, STRATOS 2, which is currently enrolling, and results from which are expected during the second half of 2012. AstraZeneca stated that whether tralokinumab is submitted for regulatory approval will depend on combined analysis of data from STRATOS 1 and STRATOS 2.
The two STRATOS studies are part of the 2298-patient ATMOSPHERE clinical trials program for tralokinumab, and were designed to evaluate the efficacy and safety of the mAb in reducing the rate of asthma exacerbations in adults and adolescents who have severe asthma that is not adequately controlled on inhaled corticosteroid (ICS) and long-acting beta2-agonist (LABA) therapies. STRATOS 1 assessed the potential use of biomarkers to identify patients with an enhanced response to tralokinumab. STRATOS 2 aims to validate the biomarker population identified in STRATOS 1.
AstraZeneca’s existing respiratory disease biologics pipeline includes benralizumab (anti-eosinophil, anti-IL-5rα), which has been accepted for regulatory review in the U.S., EU, and Japan, and the Amgen-partnered tezepelumab (anti-thymic stromal lymphopoietin; TSLP), which the firm says met its primary endpoint in a Phase IIb study.
Earlier this month AstraZeneca teamed up with Pieris Pharmaceuticals in a potentially $2.1 billion deal to develop inhaled treatments for respiratory diseases, including asthma, based on the latter’s Anticalin® platform.