Efficacy and safety of stapokibart (CM310) in uncontrolled seasonal allergic rhinitis (MERAK): an investigator-initiated, placebo-controlled, randomised, double-blind, phase 2 trial

Stapokibart: First Approval

Stapokibart (Kangyueda®; ®) is a humanised IgG4 monoclonal antibody targeted against the interleukin (IL)-4 receptor alpha subunit (IL-4Rα). By binding IL-4Rα, stapokibart blocks the binding by (and subsequent signalling of) IL-4 and IL-13, two type 2 cytokines. Stapokibart is being developed by KeyMed Biosciences for the treatment of atopic dermatitis and other type 2 inflammatory diseases. In September 2024, stapokibart received its first approval, in China, for use in the treatment of moderate-to-severe atopic dermatitis in adults whose disease is poorly controlled by, or not suitable for, topical medications. Subsequently, stapokibart additionally received approval in China for use in the treatment of chronic rhinosinusitis with nasal polyps (December 2024) and for the treatment of seasonal allergic rhinitis (February 2025). Stapokibart is also under clinical evaluation for use in the treatment of moderate-to-severe asthma and chronic obstructive pulmonary disease, and prurigo nodularis. This article summarises the milestones in the development of stapokibart leading to this first approval for moderate-to-severe atopic dermatitis.

Stapokibart for moderate-to-severe seasonal allergic rhinitis: a randomized phase 3 trial

Seasonal allergic rhinitis (SAR) places a significant socioeconomic burden, particularly on individuals with poorly managed recurrent and severe symptoms despite standard-of-care treatment. Stapokibart, a humanized monoclonal antibody that targets the interleukin (IL)-4 receptor subunit alpha, inhibits its interaction with both IL-4 and IL-13 in type 2 inflammation. Here we aim to assess the efficacy and safety of stapokibart as an add-on therapy in adults with moderate-to-severe SAR. The study was a phase 3 multicenter, randomized, double-blind, placebo-controlled clinical trial with 108 patients diagnosed with moderate-to-severe SAR and having baseline blood eosinophil counts ≥300 cells μl-1. Participants were randomized (1:1) to receive 600 mg (loading dose) to 300 mg stapokibart subcutaneously or a placebo every 2 weeks for 4 weeks. The primary endpoint was mean change from baseline in daily reflective total nasal symptom score (rTNSS) over the first 2 weeks. Multiplicity-tested secondary endpoints included changes in rTNSS over 4 weeks, reflective total ocular symptom score and Rhinoconjunctivitis Quality of Life Questionnaire score over 2 weeks and 4 weeks. Compared with the placebo, stapokibart led to a significant improvement in the mean change from baseline in daily rTNSS during the 2-week (least-squares mean difference, -1.3; 95% confidence interval, -2.0 to -0.6; P = 0.0008) and 4-week (least-squares mean difference, -1.7; 95% confidence interval, -2.5 to -0.8; P = 0.0002) treatments. Stapokibart significantly improved the multiplicity-tested secondary endpoints. Treatment-emergent adverse events were comparable between the groups. Pharmacodynamics and exploratory analyses indicated that the observed improvements in outcomes during pollen season may be attributed to the reduction of type 2 inflammation in response to stapokibart treatment. The results of this trial show that pollen seasonal administration of stapokibart improved both nasal and ocular symptoms and quality of life in patients with moderate-to-severe SAR. ClinicalTrials.gov registration: NCT05908032 .

Stapokibart (CM310) in patients with uncontrolled seasonal allergic rhinitis (PHECDA): Rationale and design of a multicentre, randomized, double-blind, placebo-controlled study

Background

Seasonal allergic rhinitis (SAR) is a global health issue, and the current standard of care (SoC) has limited effectiveness in controlling the disease. There is a need for innovative treatments to better manage uncontrolled SAR and advance beyond the uniform SoC, and biologics targeting type 2 inflammation driving allergic rhinitis is promising.

Objective

To evaluate the efficacy and safety of Stapokibart, a humanized monoclonal antibody targeting interleukin-4 receptor subunit alpha, as an add-on therapy in patients with uncontrolled SAR.

Methods

The PHECDA is a multicenter, randomized, double-blind, placebo-controlled, phase 3 clinical study designed to evaluate the efficacy and safety of Stapokibart in treating uncontrolled SAR in adults. Conducted across 18 centers in China during the pollen season, the study plans to recruit 108 adult patients with moderate to severe nasal symptoms despite receiving SoC during the previous seasonal pollen period, along with a 1-week run-in period and a baseline blood eosinophil count of at least 300 cells·μL-1. The study consists of a screening/run-in period (1 week), treatment period (4 weeks), and follow-up period (8 weeks). In addition to SoC, which includes mometasone furoate nasal spray and loratadine, participants are randomly assigned using a centralized interactive-web-response-system to receive either subcutaneous Stapokibart 600 (loading dose)-300 mg or a placebo every 2 weeks for 4 weeks. The primary endpoint of the study is the mean change from baseline in the daily reflective total nasal symptom score over the first 2 weeks of treatment. Subjects who have been administered at least 1 dose of the investigational drug will be included in the assessments of both efficacy and safety.

Results

This article outlines the methodology utilized in a multicenter trial studying Stapokibar for seasonal allergic rhinitis, with expectations to discuss its significant effects in subsequent analyses based on trial outcomes.

Conclusion

The PHECDA study is for the first time to provide insight into the efficacy and safety of a seasonal add-on Stapokibart for patients with uncontrolled SAR during pollen exposure.

Trial registration

NCT05908032.

Advances in Biologic Therapies for Allergic Diseases: Current Trends, Emerging Agents, and Future Perspectives

Biologic therapies have revolutionized the treatment of severe allergic diseases, including asthma, atopic dermatitis (AD), chronic spontaneous urticaria (CSU), chronic rhinosinusitis with nasal polyps (CRSwNP), eosinophilic gastrointestinal diseases (EGIDs), and allergic rhinitis (AR). These molecularly targeted agents provide significant benefits for patients unresponsive to conventional treatments by addressing underlying immune mechanisms, particularly type 2 inflammation driven by cytokines such as IL-4, IL-5, and IL-13. Recent advancements include biologics targeting alarmins like thymic stromal lymphopoietin (TSLP) and IL-33, which may address both type 2 and non-type 2 inflammation, broadening their therapeutic scope. Despite their effectiveness, biologics remain expensive, posing socioeconomic challenges, and there are concerns regarding long-term safety and inter-individual variability in responses. Promising innovations such as bispecific antibodies and ultra-long-acting agents are under investigation, alongside digital health tools like remote biomarker monitoring and AI-driven decision support systems, which aim to enhance personalized care. However, disparities in access, particularly for underserved populations, underscore the need for policy reforms and affordable biosimilars. This review synthesizes recent findings and emerging trends, highlighting the evolving role of biologics in transforming allergic disease management and offering insights into future research directions.

Long-term efficacy and safety of stapokibart for moderate-to-severe atopic dermatitis: 52-week results from a phase 3 trial

BACKGROUND

Management of moderate-to-severe atopic dermatitis (AD) needs long-term therapy. Stapokibart is a humanized monoclonal antibody targeting interleukin-4 receptor α subunit (IL-4Rα), a shared receptor for IL-4 and IL-13 which are key pathogenic drivers of AD. In a pivotal phase 3 trial (NCT05265923), significant higher proportions of adult AD patients receiving stapokibart than placebo achieved ≥75% improvement from baseline in Eczema Area and Severity Index (EASI-75; 66.9% vs. 25.8%) and Investigator's Global Assessment (IGA) score of 0/1 with ≥2-point reduction (44.2% vs. 16.1%) at Week 16. Herein, we report long-term (52 weeks) efficacy and safety of stapokibart from this trial.

METHODS

After 16-week double-blind treatment completed, patients in both stapokibart and placebo groups entered a 36-week maintenance treatment period and received stapokibart 300 mg every 2 weeks. Concomitant use of topical medications for AD was permitted throughout the maintenance period.

RESULTS

Of 476 patients entering maintenance period, 430 completed the treatment. At Week 52, EASI-75 was achieved in 92.5% of patients continuing stapokibart and 88.7% of those switching from placebo to stapokibart, respectively; an IGA score of 0 or 1 with a ≥2-point reduction was achieved in 67.3% and 64.2% of patients, respectively; a ≥4-point reduction in weekly average of daily Peak Pruritus Numerical Rating Scale (PP-NRS) was achieved in 67.3% and 60.5% of patients, respectively. Over the 52-week treatment period, 88.1% of patients reported treatment-emergent adverse events, most were mild or moderate.

CONCLUSION

Long-term treatment with stapokibart demonstrated a sustained efficacy and favorable safety profile in adults with moderate-to-severe AD.

Long-Term Efficacy and Safety of Stapokibart in Adults with Moderate-to-Severe Atopic Dermatitis: An Open-Label Extension, Nonrandomized Clinical Trial

BACKGROUND

Stapokibart/CM310, a humanized monoclonal antibody targeting the interleukin-4 receptor α chain, has shown promising treatment benefits in patients with moderate-to-severe atopic dermatitis in previous phase II clinical trials.

OBJECTIVE

We aimed to evaluate the long-term efficacy and safety of stapokibart in adults with moderate-to-severe atopic dermatitis.

METHODS

Enrolled patients who previously completed parent trials of stapokibart received a subcutaneous stapokibart 600-mg loading dose, then 300 mg every 2 weeks up to 52 weeks. Efficacy outcomes included the proportions of patients with ≥ 50%/75%/90% improvements from baseline of parent trials in the Eczema Area and Severity Index, Investigator's Global Assessment, and weekly average of the daily Peak Pruritus Numerical Rating Scale.

RESULTS

In total, 127 patients were enrolled, and 110 (86.6%) completed the study. At week 52, the Eczema Area and Severity Index-50/75/90 response rates were 96.3%, 87.9%, and 71.0%, respectively. An Investigator's Global Assessment 0/1 with a ≥ 2-point reduction was achieved in 39.3% of patients at week 16, increasing to 58.9% at week 52. The proportions of patients with ≥ 3-point and ≥ 4-point reductions in the weekly average of daily Peak Pruritus Numerical Rating Scale scores were 80.2% and 62.2%, respectively, at week 52. Improvement in patients' quality of life was sustained over a 52-week treatment period. Treatment-emergent adverse events occurred in 88.2% of patients, with an exposure-adjusted event rate of 299.2 events/100 patient-years. Coronavirus disease 2019, upper respiratory tract infection, and conjunctivitis were the most common treatment-emergent adverse events.

CONCLUSIONS

Long-term treatment with stapokibart for 52 weeks showed high efficacy and good safety profiles, supporting its use as a continuous long-term treatment option for atopic dermatitis.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT04893707 (15 May, 2021).