A Study to Evaluate the Pharmacodynamics, Pharmacokinetics, Safety, and Efficacy of UB-221 IV Infusion as an add-on Therapy in Patients With Chronic Spontaneous Urticaria

UB-221 is a recombinant humanized IgG1 monoclonal antibody with neutralizing capability against soluble human IgE and CD23-bound IgE for the treatment of allergic diseases. The activity of UB-221 is directly through the high-affinity binding with soluble and membrane bound IgE. The neutralization of soluble IgE will desensitize the activation of mast cells and basophils by inhibiting IgE cross-linking and down-regulation of FcεRI (high affinity IgE receptor) expression on those cells. The binding to CD23-bound IgE may inhibit IgE synthesis by stabilization of membrane-bound CD23 on B lymphocytes.

sterile saline solution (0.9% NaCl) for intravenous (IV) infusion