A Multiple Ascending Dose, Phase 1b Study of YH35324 in Atopic Healthy Subjects or Subjects With Allergic Diseases

A Randomized, Double-Blind, Placebo/Active Controlled, Multiple Ascending Dose, Phase 1b Study to Evaluate the Safety, Tolerability, Pharmacokinetics and Pharmacodynamics Following Subcutaneous Injections of YH35324 in Atopic Healthy Subjects or Subjects With Allergic Diseases

This study aims to evaluate the safety, tolerability, pharmacokinetic (PK) and pharmacodynamic (PD) profiles following multiple subcutaneous injections of YH35324 in healthy subjects or subjects with allergic diseases, who have atopy.

YH35324 is a drug under development as a novel therapeutic agent for various IgE-mediated allergic diseases. Since YH35324 has a high binding affinity to human IgE, it prevents serum IgE from binding to receptors on mast cells and basophil, thereby inhibiting histamine release caused by degranulation when exposed to allergens. This study aims to evaluate the safety, tolerability, pharmacokinetic (PK) and pharmacodynamic (PD) profiles following multiple subcutaneous injections of YH35324 in healthy subjects or subjects with allergic diseases, who have atopy.

Inclusion Criteria:

• Male or female adults aged ≥ 19 to ≤ 55 years(Cohort 5, Mald or female adults ≥ 19)
• Serum total IgE level ≥ 30 IU/mL or 30 to 700 IU/mL or >700IU/mL(Not Applicable for Cohort 5)
• Meeting the following cohort-specific disease severity criteria [Cohorts 1-4]: Healthy subjects without any pathological symptoms or findings from medical examination, or subjects with a history of mild allergic diseases (allergic rhinitis, atopic dermatitis, food allergy, urticaria, or allergic asthma) [Cohort 5]: Subject who have been diagnosed with moderate to severe atopic dermatitis

Exclusion Criteria:

• History of malignancy
• Positive drug screen result
• transaminase (AST) or alanine transaminase (ALT) level > 2 X the upper limit of normal
• Estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m2 using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formula
• Allergy immunotherapy initiated or changed within 6 months prior to randomization(For Cohort 5, within 12 months prior to randomization)
• History of participation in another clinical trial within 6 months prior to randomization