Stapokibart Successfully Treats Refractory CSU After Omalizumab Failure in New Case Report

A recently published case report describes successful treatment of refractory chronic spontaneous urticaria (CSU) with stapokibart following failure of omalizumab therapy, highlighting the potential role of targeting type 2 inflammation in the disease.¹

Case Overview and Mechanism of Action

CSU affects approximately 1% of the population worldwide and persists beyond 1 year in over 80% of patients.² Although second-generation H1 antihistamines remain first-line therapy and omalizumab is widely used for patients with antihistamine-refractory disease, a subset of patients continue to experience persistent symptoms despite treatment. Management options for these individuals remain limited.

The report details the case of a patient with severe CSU whose disease remained uncontrolled despite treatment with omalizumab (300 mg every 3 weeks). After inadequate response to standard therapies, the patient was treated with stapokibart, a monoclonal antibody targeting the interleukin (IL)-4 receptor alpha (IL-4Rα), thereby inhibiting signaling from both IL-4 and IL-13, key cytokines involved in type 2 inflammatory pathways. It is currently approved in China for moderate to severe atopic dermatitis inadequately controlled by topical therapies, seasonal allergic rhinitis, and severe uncontrolled chronic rhinosinusitis with nasal polyps.

Patient Response and Clinical Outcomes

The 44-year-old female patient experienced substantial clinical improvement following initiation of stapokibart in December 2024. With a 600 mg loading dose and then 300 mg thereafter every 2 weeks, disease activity decreased significantly, with marked reductions in urticaria symptoms and improved disease control. Changes in disease activity and quality of life scores were as follows:

• Initial presentation (September 2024):
  • UCT: 8
  • UAS7: 16
  • DLQI: 8
• After omalizumab-based therapy (December 2024):
  • UCT: 6
  • UAS7: 30
  • DLQI: 21
• After stapokibart treatment (Week 19):
  • UCT: 15
  • UAS7: 0
  • DLQI: 1
• After dose-interval extension and 3-month post-treatment follow-up:
  • UCT: 16
  • UAS7: 0
  • DLQI: 0

The case adds to growing evidence suggesting that type 2 inflammatory pathways may play an important role in CSU pathogenesis, particularly among patients who do not respond adequately to anti-IgE therapy. While omalizumab targets circulating IgE and downstream mast cell activation, IL-4 and IL-13 signaling may contribute to persistent inflammation through complementary mechanisms that are not fully addressed by anti-IgE treatment alone. By blocking IL-4Rα, stapokibart may modulate several components of type 2 immune responses implicated in disease activity.

Limitations and Future Outlook

No significant safety concerns were reported during treatment. Although encouraging, the findings are limited by the nature of a single-patient case report. The authors emphasize that larger clinical studies are needed to better define the efficacy and safety of stapokibart in CSU and to identify which patients may be most likely to benefit from this therapeutic approach.

The report nevertheless contributes to a growing body of literature exploring biologic therapies beyond anti-IgE treatment for CSU. As understanding of disease mechanisms continues to evolve, investigators are increasingly examining therapies that target broader type 2 inflammatory pathways.

While definitive conclusions cannot be drawn from a single case, the successful outcome observed with stapokibart suggests that targeting IL-4 and IL-13 signaling may represent a promising avenue for patients who remain symptomatic despite currently available therapies. Further prospective studies will be necessary to confirm these observations and clarify the role of IL-4Rα inhibition in the CSU treatment landscape.

References

1. Chen J, Chen Z, Li X, et al. Successful Treatment of Refractory Chronic Spontaneous Urticaria with Stapokibart After Omalizumab Failure: A Case Report. Clin Cosmet Investig Dermatol. 2026;19:603129. Published 2026 May 25. doi:10.2147/CCID.S603129

2. Fricke J, Ávila G, Keller T, et al. Prevalence of chronic urticaria in children and adults across the globe: Systematic review with meta-analysis. Allergy. 2020;75(2):423-432. doi:10.1111/all.14037