Successful OSMO study shows Nucala improved asthma control in patients uncontrolled on Xolair .- GSK.

GSK has presented positive results from the OSMO study at the American Academy of Allergy, Asthma & Immunology (AAAAI) and World Allergy Organization (WAO) Joint Congress in Orlando. The results showed that severe asthma patients who are uncontrolled despite receiving Xolair (omalizumab) and who are eligible for treatment with Nucala (mepolizumab), experience improved asthma control when switched on to mepolizumab.

OSMO is an open-label, single-arm study which investigated whether patients who had been receiving omalizumab, (a biologic targeting IgE in patients with allergic sensitisation) for an average of 2.5 years and continued to have uncontrolled severe asthma, gained better asthma control following a switch to mepolizumab, (a biologic targeting IL-5 for patients with severe eosinophilic asthma). In the study 145 patients, who were documented to have experienced at least two asthma exacerbations in the year prior to enrolment, were switched directly to mepolizumab without a wash-out period and followed for 32 weeks. In this study, mepolizumab data compared with baseline values prior to first dose, unless otherwise stated: Met the primary endpoint of asthma control with clinically significant improvements, as evaluated by the Asthma Control Questionnaire (ACQ-5), with a mean change from baseline of -1.45 at week 32. Met all secondary endpoints and other key endpoints: Rate of exacerbations requiring oral steroids reduced by 64% vs prior 12 months (3.26 to 1.18). Rate of exacerbations requiring an ED visit or hospitalization reduced by 69% vs prior 12 months (0.63 to 0.19). Improvement in lung function (pre-bronchodilator FEV1) of 159 mL vs baseline. Improvement in Quality of life as evaluated by the SGRQ (-19 units, compared with MCID -4.0) vs baseline. Reduction in blood eosinophils of approximately 80% by Week 4 (vs baseline), which was sustained until Week 32. Safety profile was consistent with the known profile of the treatment.

In a further abstract/poster presented at AAAAI/WAO Joint Congress, a pooled, post-hoc meta-analysis of data from the MENSA and MUSCA studies, mepolizumab showed improvements in lung function of patients with severe eosinophilic asthma, measured by morning peak expiratory flow (AM PEF), compared with placebo. Early improvements were seen in week one and sustained at the end of the observational period: the mean change in AM PEF at week one was 10 L/min in the mepolizumab group compared with 2L/min in the placebo group and at the end of the observational period the mean change in AM PEF was 26 L/min in the mepolizumab group compared to 4 L/min in the placebo group. This improvement was shown to be greater at higher eosinophil counts.

About the OSMO study : OSMO was an international, open-label, single arm trial. It enrolled patients aged 12 and older with severe eosinophilic asthma who were receiving omalizumab, but were not optimally controlled, based on A sthma Control Questionnaire score of >1.5 at screening and baseline and who experienced > 2 exacerbations in the past 12 months. The Asthma Control Questionnaire (ACQ-5) is a validated, self-administered tool, used by physicians to assess asthma control and changes in asthma control. Patients also required a peripheral eosinophil blood count of ?150 cells/�L at study start or ?300 cells/�L in the past 12 months to be eligible for mepolizumab.