Imagine battling severe asthma that sends you to the hospital year after year – now, a groundbreaking drug could change that with just two doses annually. That's the exciting promise of Exdensur (depemokimab-ulaa), a new medication from GSK that's just been greenlit by the US Food and Drug Administration (FDA) for tackling severe asthma in adults and kids aged 12 and up, specifically when it's driven by an eosinophilic phenotype. For beginners, let's break that down: eosinophilic asthma is a subtype where your body produces too many eosinophils – a kind of white blood cell that fuels inflammation – leading to more asthma attacks. This approval isn't just a minor update; it's a game-changer for millions grappling with this relentless condition. But here's where it gets controversial: while biologics like this have shown real benefits, they're still underused, leaving many patients at risk. What do you think – is it time to make these treatments more accessible and affordable for everyone who needs them?
GSK plc (traded on LSE/NYSE: GSK) proudly shared this news from London, UK, aimed at media and investors. You can grab the full press release as a PDF here (it's about 234.3KB): https://www.gsk.com/media/5aubxrcf/sea-exdensur-depemokimab-approved-by-us-fda.pdf. The FDA's stamp of approval means Exdensur is now available as an additional maintenance therapy for severe asthma characterized by that eosinophilic trait in patients 12 years and older.
This decision leans heavily on robust evidence from two phase III trials, SWIFT-1 and SWIFT-2. These studies proved that depemokimab keeps asthma attacks at bay with just two injections per year, on top of the usual standard care treatments. And this is the part most people miss: the results were impressive, showing a drop in yearly asthma flare-ups by 58% in SWIFT-1 and 48% in SWIFT-2 over a full year. To put numbers to it, the rate ratio (with 95% confidence interval and p-value) for SWIFT-1 was 0.42 (0.30, 0.59) at p<0.001, and for SWIFT-2, it was 0.52 (0.36, 0.73) at p<0.001. That translates to annual exacerbation rates (AER) of 0.46 versus 1.11 for depemokimab vs. placebo in SWIFT-1, and 0.56 versus 1.08 in SWIFT-2 – meaning fewer scary attacks per year for those on the drug.
Diving deeper into secondary findings from both trials, patients on depemokimab had noticeably fewer severe flare-ups that landed them in the hospital or emergency room: just 1% and 4% in SWIFT-1 and SWIFT-2, respectively, compared to 8% and 10% on placebo. A combined analysis across the trials revealed an even starker reduction – a 72% drop in the yearly rate of significant exacerbations needing hospital or ED care, with a rate ratio of 0.28 (95% CI: 0.13, 0.61) and a nominal p-value of 0.002. The AER here was 0.02 for depemokimab versus 0.09 for placebo. Importantly, the safety profile was reassuring; depemokimab was well-tolerated, with side effects similar in frequency and intensity to those seen with placebo.
Kaivan Khavandi, GSK's Senior Vice President and Global Head of Respiratory, Immunology & Inflammation R&D, expressed enthusiasm: “US doctors can now offer lasting shield against flare-ups for those with severe eosinophilic asthma, all with just two annual doses. Exdensur has the potential to transform care and solidify biologics as a go-to for patients still suffering breakthroughs on other treatments.”
What sets depemokimab apart is its innovative design with a longer half-life, allowing it to steadily curb the type 2 inflammation fueling the disease, all with semi-annual dosing. For those new to this, type 2 inflammation involves overactive immune responses that worsen asthma symptoms. These features might not only boost patient results but also ease the load on healthcare systems by cutting down on frequent visits.
Picture this: Roughly 2 million Americans endure severe asthma, and half of them still face regular exacerbations that often mean hospital stays, ER trips, and ballooning healthcare bills. While biologic drugs have helped manage severe asthma effectively, only about 20% of those eligible in the US actually get them, heightening their chances of worsening attacks. Extending dosing schedules, like with depemokimab, could encourage more uptake – studies show 73% of doctors see value in it, and patients might be more likely to stick with a treatment that doesn't require constant injections.
Geoffrey Chupp, MD, a Professor of Medicine specializing in Pulmonary, Critical Care, and Sleep Medicine at Yale University, weighed in: “Many biologic asthma therapies aren't used enough, and their frequent need for shots can be a hassle, leading to spotty adherence. This opens the door for extended protection against flare-ups with fewer injections for severe asthma sufferers, potentially lowering overall healthcare demands. Exdensur might help doctors and patients hit their goals more easily.”
Tonya Winders, President and CEO of the Global Allergy & Airways Patient Platform, added a patient's perspective: “Living with severe asthma is a daily fight, with many dealing quietly with ongoing symptoms and attacks. A cutting-edge option like Exdensur, providing extended relief from exacerbations for eosinophilic severe asthma patients and requiring fewer doses, is a breath of fresh air.”
Depemokimab has also earned marketing approval from the UK's Medicines and Healthcare products Regulatory Agency (MHRA), plus a favorable opinion from the European CHMP, with a final nod anticipated in the first quarter of 2026. Applications are pending worldwide, including in China and Japan.
Understanding Severe Asthma
Severe asthma is identified when the condition demands medium- to high-dose inhaled steroids plus another medication, like oral steroids or a biologic, to keep it under control – or if it stays unruly despite treatment. Think of it as asthma that's hard to tame. Over 80% of severe cases stem from type 2 inflammation, where eosinophils – those white blood cells – are elevated, driving the problem. For example, a patient might have frequent wheezing, shortness of breath, and chest tightness that's not fully managed by standard inhalers.
About Exdensur (depemokimab-ulaa)
Exdensur stands out as the pioneering ultra-long-acting biologic aimed at respiratory issues rooted in type 2 inflammation, starting with severe asthma. Its engineered extended half-life supports dosing just twice a year, making it a convenient alternative for ongoing management.
Check out the full US Prescribing Information here: https://gskpro.com/content/dam/global/hcpportal/enUS/PrescribingInformation/Exdensur/pdf/EXDENSUR%E2%80%A6.
Details on the SWIFT Phase III Trials
Findings from these trials were showcased at the 2024 European Respiratory Society International Conference (link: https://publications.ersnet.org/content/erj/64/suppl68/rct3718) and featured in the New England Journal of Medicine (link: https://www.nejm.org/doi/pdf/10.1056/NEJMoa2406673).
SWIFT-1 and SWIFT-2 evaluated depemokimab's effectiveness and safety as an add-on in 382 and 380 severe asthma patients, respectively. Participants were randomly assigned to depemokimab or placebo alongside their regular care, which included medium-to-high-dose inhaled corticosteroids and at least one other controller. The full analysis set for SWIFT-1 had 250 on depemokimab plus standard care and 132 on placebo; SWIFT-2 included 252 and 128 in those groups.
The Depemokimab Development Program
The phase III lineup includes SWIFT-1 and SWIFT-2 for severe asthma, along with an open-label extension called AGILE, and ANCHOR-1 and ANCHOR-2 for chronic rhinosinusitis with nasal polyps (CRSwNP). Depemokimab is also in phase III testing for other type 2 inflammation-driven conditions, such as OCEAN for eosinophilic granulomatosis with polyangiitis (EGPA) and DESTINY for hypereosinophilic syndrome (HES). GSK's launched ENDURA-1, ENDURA-2, and VIGILANT phase III studies to assess depemokimab as an add-on for uncontrolled moderate-to-severe chronic obstructive pulmonary disease (COPD) involving type 2 inflammation.
GSK's Role in Respiratory Health
Building on years of innovation, GSK aims to set bolder goals for treatment, advance next-level standards, and reshape the landscape of respiratory care for hundreds of millions affected by these diseases. With a top-tier lineup of respiratory products – including vaccines, precision biologics, and inhaled therapies – GSK focuses on enhancing results and quality of life for those with various asthma types, COPD, obscure conditions like refractory chronic cough, or rare ones such as systemic sclerosis with interstitial lung disease. They're leveraging cutting-edge science and tech to address root causes and halt disease progression.
About GSK
GSK is an international biopharma leader dedicated to blending science, technology, and expertise to outpace diseases. Learn more at gsk.com.
Forward-Looking Statements Caution
GSK reminds investors that any forward-looking remarks in this announcement, including projections, carry risks that could lead to actual outcomes diverging from expectations. Factors might include those outlined in GSK's Annual Report on Form 20-F for 2024 and Q3 Results for 2025.
What are your thoughts? Do you believe this approval will truly revolutionize asthma care, or are there hurdles like cost and access that need tackling first? Is the emphasis on fewer doses a game-changer for patient adherence, or could it downplay the need for comprehensive monitoring? Share your opinions in the comments – agree or disagree, we'd love to hear!
