A Study of MG-K10 in Chronic Spontaneous Urticaria

Inclusion Criteria: 1. Aged ≥12 and ≤75 years, body weight ≥30 kg, voluntarily sign ICF. 2. Diagnosed with CSU for ≥6 months, with pruritus and wheals for \>6 weeks despite using second-generation H1 antihistamines. 3. Within 7 days prior to randomization: UAS7 score ≥16, ISS7 score ≥8, and at least one UAS ≥4. 3.Willing to maintain stable background antihistamine dose during the study (up to 4 times standard dose allowed). 4.Agree to use effective contraception during the study and for 6 months after last dose. Exclusion Criteria: 1. Inducible urticaria (e.g., dermographism, cold, heat, cholinergic) or other chronic pruritic skin diseases (e.g., atopic dermatitis) affecting study assessment. 2. Active tuberculosis, or untreated latent TB; serious active infections. 3. Known or suspected immunodeficiency, or history of invasive opportunistic infections. 4. Known allergy to study drug or excipients. 5. Prior use of MG-K10 or other biologics (anti-IL-4Rα, anti-IgE, etc.) within 16 weeks or 5 half-lives. 6. Use of immunosuppressants, systemic corticosteroids, phototherapy, or Chinese herbal medicine within 4 weeks prior to first UAS assessment. 7. Clinically significant laboratory abnormalities at screening: ANC \<1.2×10⁹/L, platelets \<90×10⁹/L, ALT/AST/total bilirubin \>2×ULN, creatinine \>1.5×ULN. 8. Positive for HBsAg, or HBcAb positive with HBV-DNA ≥1×10³ copies/ml; HCV-Ab positive with HCV-RNA positive; HIV antibody positive. 9. QTcF \>500 msec or other clinically significant ECG abnormalities. 10. Pregnant, breastfeeding, or planning pregnancy during the study. 11. History of malignant tumors within 5 years (except adequately treated non-melanoma skin cancer or cervical carcinoma in situ). 12. Participated in another clinical study and used investigational drug within 12 weeks or 5 half-lives prior to first UAS assessment.