GSK announced that a phase IIIb study evaluating its respiratory drug Nucala (mepolizumab) met all its primary and secondary endpoints.
The MUSCA study showed that patients with severe asthma driven by eosinophilic inflammation when treated with the Nucala added-on to standard of care achieved clinically and statistically significant improvements in their health-related quality of life and lung function when compared with patients treated with placebo and standard of care.
The study involved 551 patients treated with Nucala 100mg subcutaneous injection, every 4 weeks for a 24 week period. The results were based on St. Georges Respiratory Questionnaire (SGRQ) score, which is a patient-reported outcome measure used to understand how severe asthma affects a patient’s quality of life. The SQRQ scores showed that Nucala improved quality of life by 7.7 units compared to baseline versus placebo after 24 weeks. The result was also nearly double the defined clinically meaningful difference of ≥4.0 units.
The study also met exploratory endpoints where the annual rate of exacerbations (asthma attacks)was reduced by 58%, and the number of exacerbations requiring emergency room visits or hospitalisation was reduced by 68% for people treated with Nucala compared with placebo.
In the US, Nucala is presently approved as an add-on maintenance treatment for patients with severe asthma and with an eosinophilic phenotype. However, Nucala is not approved for the treatment of other eosinophilic conditions or relief of acute bronchospasm or status asthmaticus.
The positive data from the MUSCA study highlight the importance of Nucala as a treatment option for patients with severe asthma with an eosinophilic phenotype. Nucala can prove to be of an effective treatment option as it demonstrated improvements in markers of asthma control including quality of life and lung function, thus treating most severe asthma patients.