A Phase 2a Study of TAS5315 in Patients With Chronic Spontaneous Urticaria

Key Inclusion Criteria:

• Aged 18 to 75 years

• Diagnosis of chronic spontaneous urticaria (CSU)

• Presence of itch and hives for at least 6 consecutive weeks prior to screening in spite of use of non-sedating H1-antihistamines for CSU

• UAS7 score ≥ 16 and HSS7 score ≥ 8 during 7 days prior to study entry

• In-clinic UAS ≥ 4 on study entry

• Willing and able to complete and Participate Daily for the duration of the study

Key Exclusion Criteria

• Diseases other than CSU with symptoms of urticaria or angioedema, including urticarial vasculitis, erythema multiforme, mastocytosis, or hereditary or acquired angioedema

• Atopic dermatitis, psoriasis, ichthyosis, or other skin disease associated with chronic itching

• Bleeding diathesis

• Uncontrolled hypertension disease states

• Treatment with omalizumab or other humanized anti-human IgE monoclonal antibody therapies used to treat CSU within 4 months prior to screening

• Nonresponse to omalizumab or other humanized anti-human IgE monoclonal antibody therapies

• Have been treated with other Bruton's Tyrosine Kinase inhibitors

• Pregnant or lactating women