GlaxoSmithKline has announced data demonstrating that severe asthma patients, whose disease is driven by eosinophilic inflammation, treated with first-in-class biologic Nucala (mepolizumab) added-on to standard of care, achieved clinically and statistically significant improvements in their health-related quality of life and lung function, when compared to patients treated with placebo and standard of care. These results are from the phase IIIb MUSCA study (NCT02281318, 200862), which successfully met all its primary and secondary endpoints.
Results of the study, presented at the American Academy of Allergy, Asthma & Immunology (AAAAI) annual meeting, showed in patients treated with mepolizumab as an add on to standard care.
Georges Respiratory Questionnaire (SGRQ) score (primary endpoint), a measure of quality of life, improved by 7.7 units from baseline vs. placebo (p=0.001) after 24 weeks – nearly double the defined clinically meaningful difference of =4.0 units.
Lung function (first secondary endpoint), as measured by pre-bronchodilator FEV1, increased by 120mL (p=0.001) more than in placebo patients at week 24 – a clinically relevant and statistically significant improvement.
FEV1 and SGRQ scores were also measured during the study, with improvements seen at the first measurement interval, after the first four weeks and sustained throughout the 24-week trial.
Asthma control, as measured by the Asthma Control Questionnaire-5 (ACQ-5) (additional secondary endpoint), showed a significant improvement vs. placebo in the mepolizumab treatment group by 0.40 units (p<0.001).
SGRQ score is an important patient-reported outcome measure used to understand how severe asthma affects a patient’s quality of life. It looks at symptoms, activity levels and the impact asthma is having on people with the disease from a physiological and social perspective. MUSCA is the first mepolizumab clinical trial to specifically look at health-related quality of life as a primary endpoint and assess SGRQ score on multiple occasions throughout the study. FEV1 is a measure of how much air a person can forcefully blow out of their lungs and is used to assess how a patient’s breathing is improving. In the clinical development program, mepolizumab did not provide consistent improvements in mean change from baseline in FEV1.
Dr Frank Albers, Medical Affairs Lead for Nucala, GSK said “The data from the MUSCA study underscore the importance of Nucala as a treatment option for patients with severe asthma with an eosinophilic phenotype. These are patients who have very limited treatment options to control their asthma. For them shortness of breath, wheezing, coughing and the risk of an asthma attack is an ever present occurrence and one that can have a severe impact their life on a daily basis. By demonstrating improvements in a range of important markers of asthma control, including quality of life and lung function, these data reinforce the valuable role Nucala can play in the treatment of some of the most severe asthma patients.”
Exploratory endpoints were the annual rate of exacerbations (asthma attacks), which was reduced by 58 per cent, and the number of exacerbations requiring emergency room visits or hospitalisation, which was reduced by 68 per cent for people treated with mepolizumab compared with placebo. These results were comparable to those seen in the pivotal phase III MENSA study. Safety was also assessed and the safety profile of mepolizumab in the MUSCA study was consistent with the product label for Nucala.
The MUSCA study (Mepolizumab adjUnctive therapy in subjects with Severe eosinophiliC Asthma) involved 551 patients treated with Nucala 100mg subcutaneous injection, every 4 weeks for a 24 week period. The MUSCA study is the first clinical trial designed primarily to assess the effect of mepolizumab on disease-specific health-related quality of life using the St George’s Respiratory Questionnaire (SGRQ) in patients with severe asthma with an eosinophilic phenotype. Using a series of questions that patients complete themselves, the SGRQ looks at how a patient’s asthma symptoms impact on everyday activities, such as walking, housework, going to the shops, gardening or light exercise, and whether their severe asthma prevents them from doing activities they might otherwise expect to do.