GSK’s twice-yearly depemokimab reduced asthma attacks by half and cut clinic visits by nearly three-quarters, positioning it for an estimated $4 billion in peak sales if approved.
GSK’s new long-acting asthma treatment reduced serious attacks by more than 50% and led to a 72% reduction in exacerbations that required hospitalization or an ER visit, according to detailed Phase III data revealed at the European Respiratory Society and published in the New England Journal of Medicine on Monday.
The full readout comes after GSK revealed in May that depemokimab met the primary endpoints in two late-stage trials called SWIFT-1 and SWIFT-2. The studies compared the therapy to placebo in adults and adolescents with severe asthma with type 2 inflammation characterized by blood eosinophil count.
Patients in the parallel trials had a 54% reduction in severe exacerbations or serious asthma attacks and a 72% reduction in exacerbations that required hospitalization or emergency department visits, GSK said. The studies met the main goal of achieving s statistically significant and clinically meaningful reduction in exacerbations over 52 weeks as comparfed to placebo.
Depemokimab, an anti-IL-5 therapy, missed on a secondary endpoint that looked at overall health and quality of life, as well as one that examined the severity of disease via forced expiratory volume. GSK’s Kaivan Khavandi, global head of Respiratory/Immunology R&D, explained in a call with reporters that there was a high placebo response on those endpoints. The miss is not expected to impact GSK’s strategy as reducing the actual exacerbations is the tougher and more important clinical outcome, he said.
The treatment is one of GSK’s planned 12 major product launches over the next few years that are expected to generate £38 billion ($50 million) in sales by 2031. The drug itself is expected to bring in £3 billion ($4 billion) in peak sales if approved.
Patients with severe asthma already have a number of approved options, but Khavandi said that there’s an unmet need for less burdensome treatments. Existing options include GSK’s own Nucala, which was originally approved in 2015 for severe asthma. It has since garnered multiple expansions for related conditions and patient populations.
Other competitors in the anti–IL-5 class include Teva Pharma’s Cinqair and AstraZeneca’s Fasenra.
“We know from real world data that 40% of participants taking those short acting biologics discontinued treatments by one year,” Khavandi said in a call with reporters. “And of course, this is a chronic condition where it’s fundamentally important that there’s sustained suppression of inflammation to be able to have that durability in reducing exacerbations.”
Depemokimab is administered by injection twice yearly, which Khavandi said should lead to increased adherence and durability of treatment. This attribute will become a key pillar of GSK’s marketing strategy as depemokimab moves toward launch. The company said it intends to immediately take the data to regulators around the world.
At the same time, GSK is testing depemokimab in several other indications including chronic rhinositis with nasal polyps. The company intends to coordinate its submission strategy for the two lead indications.
Data from the depemokimab trials has also shown structural changes in airway remodeling, which is suggestive that the drug could be getting to the underlying cause of the disease, Khavandi explained.
