GlaxoSmithKline plc (LSE/NYSE: GSK) today announced that the first patient has been dosed in the SWIFT-2 trial as part of the phase 3 clinical programme investigating the safety and efficacy of GSK3511294 (?GSK?294?) in severe eosinophilic asthma (SEA). GSK?294 is an investigational medicine with potential to be the first biologic to deliver long-acting suppression of IL-5 in patients with SEA from one subcutaneous injection every six months. Christopher Corsico, Senior Vice President Development, GSK, said:??Around 10% of all asthma patients suffer from the avoidable symptoms of severe eosinophilic asthma and only one in four patients who are eligible for a biologic therapy currently receive one. These patients might benefit from more targeted therapies to better control their condition. We believe GSK?294 could provide another option to these patients that build on the positive impact seen with current anti-IL5 treatments and may also offer the advantage of one subcutaneous injection every six months.? GSK?294 is an anti-IL-5 monoclonal antibody currently in development for the treatment of severe eosinophilic asthma. It is a distinct, new biologic entity and has been engineered for high affinity and long-acting suppression of IL-5 function. IL-5 is the major cytokine responsible for the proliferation, activation and survival of eosinophils, making it a proven treatment target for severe asthma patients with higher levels of eosinophils. In patients with severe eosinophilic asthma, targeted anti-IL-5 therapies are a well-established and effective treatment approach. GSK?294 has progressed from phase 1 to phase 3 studies in three and a half years. The planned phase 3 programme, which involves three studies and 2,450 patients, will assess the efficacy and safety of GSK?294.

• SWIFT 1?(N=375) and?SWIFT 2?(N=375) will assess the efficacy and safety of GSK?294 in participants with severe uncontrolled asthma with an eosinophilic phenotype despite standard of care treatment with medium to high dose inhaled corticosteroids plus at least one additional controller.
• NIMBLE?(N=1700 patients) will assess whether participants with severe asthma with an eosinophilic phenotype, who are currently benefitting from mepolizumab or benralizumab treatment can maintain treatment benefit when switched to GSK?294. Throughout the study, all participants will continue their non-biologic baseline standard of care asthma treatment.

About severe asthma and eosinophilic inflammation Severe asthma is defined as asthma which requires treatment with medium or high dose inhaled corticosteroids (ICS) plus a second controller (and/or systemic corticosteroids) to prevent it from becoming ?uncontrolled? or which remains ?uncontrolled? despite this therapy. Severe asthma patients are also often categorised by long-term use of oral corticosteroids (OCS). ?Eosinophils play a core role in more than 50% of patients with severe asthma, providing a proven target for treatment. GSK?s commitment to respiratory disease For over 50 years, GSK has led the way in developing medicines that advance the management of asthma and COPD. From introducing the world?s first selective short-acting beta agonist in 1969, to launching six treatments in five years to create today?s industry-leading respiratory portfolio, we continue to innovate so we can reach the right patients, with the right treatment. Working together with the healthcare community, we apply world-class science to discover and understand the molecules that become the medicines of tomorrow. We won?t stand still until the simple act of breathing is made easier for everyone. About GSK GSK is a science-led global healthcare company with a special purpose: to help people do more, feel better, live longer. For further information please visit?www.gsk.com/about-us. Cautionary statement regarding forward-looking statements GSK cautions investors that any forward-looking statements or projections made by GSK, including those made in this announcement, are subject to risks and uncertainties that may cause actual results to differ materially from those projected. Such factors include, but are not limited to, those described in the Company's Annual Report on Form 20-F for 2020 and any impacts of the COVID-19 pandemic.