GSK plc has announced that the US Food and Drug Administration has approved Exdensur (depemokimab-ulaa) as an add-on maintenance treatment for severe asthma characterised by an eosinophilic phenotype in adults and paediatric patients aged 12 years and older. Exdensur is the first and only ultra-long-acting biologic approved for this patient group with a twice-yearly dosing schedule.
The approval is based on results from the phase III SWIFT-1 and SWIFT-2 clinical trials, which evaluated depemokimab in addition to standard of care versus placebo plus standard of care over 52 weeks. The studies demonstrated sustained and statistically significant reductions in asthma exacerbations with two doses per year.
Hospitalisation or emergency visit rates were 1% and 4% in the depemokimab groups versus 8% and 10% in the placebo groups. A pre-specified pooled analysis of both trials demonstrated a 72% reduction in the annualised rate of clinically significant exacerbations requiring hospitalisation or emergency department visits over 52 weeks, with an annualised rate of 0.02 for depemokimab versus 0.09 for placebo. Across both trials, depemokimab was generally well tolerated, with a similar rate and severity of side effects to placebo.
Depemokimab has been developed with an extended half-life, enabling sustained suppression of type 2 inflammation with twice-yearly dosing. GSK noted that this dosing profile may help reduce treatment burden and improve adherence while addressing ongoing unmet needs in severe asthma care.
An estimated two million people in the United States live with severe asthma, and around half continue to experience frequent exacerbations and hospitalisations despite available treatments. While biologics have shown benefit in managing severe asthma, only about 20% of eligible patients in the US currently receive them.
Exdensur has also received marketing authorisation from the UK’s Medicines and Healthcare products Regulatory Agency and a positive opinion from the European Medicines Agency’s Committee for Medicinal Products for Human Use, with a final European decision expected in the first quarter of 2026. Regulatory submissions are under review in other regions, including China and Japan.
