GSK plc has announced positive results from its Phase 3 ANCHOR-1 and ANCHOR-2 clinical trials, evaluating depemokimab in adult patients with chronic rhinosinusitis with nasal polyps (CRSwNP). The studies met their primary endpoints, demonstrating a statistically significant reduction in nasal polyp size and nasal obstruction compared to placebo plus standard of care over a 52-week period. These findings suggest that depemokimab could offer a targeted treatment for the millions affected by uncontrolled CRSwNP.
Efficacy and Safety in ANCHOR Trials
The ANCHOR-1 and ANCHOR-2 trials were replicate, randomized, double-blind, placebo-controlled, multi-center studies. In ANCHOR-1, the full analysis set included 143 patients in the depemokimab arm and 128 in the placebo arm. ANCHOR-2 included 129 patients in the depemokimab arm and 128 in the placebo arm. The co-primary endpoints were the change from baseline in total endoscopic nasal polyp score at 52 weeks and the change from baseline in mean nasal obstruction score from weeks 49 to 52. The overall incidence and severity of treatment-emergent adverse events were similar between the depemokimab and placebo groups, indicating a favorable safety profile.
Kaivan Khavandi, SVP, Global Head of Respiratory/Immunology R&D at GSK, stated, “Globally millions of people suffer from uncontrolled CRSwNP, the majority of whom will exhibit markers of type 2 inflammation... We’re very encouraged by the results from the ANCHOR studies, which demonstrate the potential for depemokimab to offer targeted and sustained suppression of a key inflammatory pathway underlying nasal polyp growth and nasal obstruction.”
Depemokimab: An Ultra-Long-Acting Biologic
Depemokimab is the first ultra-long-acting biologic to be evaluated in Phase 3 trials for CRSwNP. It features an extended half-life, high binding affinity, and potency for interleukin-5 (IL-5), a key cytokine in type 2 inflammation. IL-5 is present at high levels in nasal polyp tissue. This allows for a convenient once-every-six-month dosing schedule.
CRSwNP: A Chronic Inflammatory Condition
Chronic rhinosinusitis with nasal polyps (CRSwNP) is a chronic condition affecting up to 4% of the general population, with approximately 40% experiencing uncontrolled disease. It is characterized by inflammation of the nasal lining, leading to the development of soft tissue growths known as nasal polyps. Symptoms include nasal obstruction, loss of smell, facial pressure, sleep disturbance, infections, and nasal discharge, significantly impacting patients' quality of life.
Up to 80% of CRSwNP patients exhibit evidence of type 2 airway inflammation, often detected by elevated blood eosinophil counts. These patients frequently have a history of sinonasal surgery and high exposure to oral corticosteroids, which are associated with significant complications.
Regulatory Pathway and Future Prospects
GSK plans to use data from the ANCHOR-1 and ANCHOR-2 trials, along with data from the SWIFT-1 and SWIFT-2 Phase 3 trials of depemokimab in severe asthma, for regulatory submissions worldwide. Depemokimab is currently not approved for any indication. GSK anticipates that depemokimab could generate peak annual sales of up to £3 billion ($3.9 billion). The company hopes to launch the drug for use with several medical conditions between 2026 and 2027.
