The decision to discontinue the study was made after observing moderate drug induced liver injury in two subjects enrolled in the first dose cohort.

This is a phase 1b, open label, non-randomized, sequential dose-escalation, multicenter trial in adult patients with chronic cold urticaria.

Key Inclusion Criteria:

1. Women and Men ages 18-75
2. Diagnosed with chronic, cold inducible urticaria for at least 3 months prior to starting the study and refractory to antihistamine treatment
3. Positive cold stimulation test assessed by TempTest® at the Screening and Baseline visits
4. Considered healthy as assessed by medical evaluation including review of medical history, physical examination, vital signs, laboratory tests and ECG recording
5. Willing and able to participate in all visits, undergo all study procedures and adhere to study restrictions

Key Exclusion Criteria:

1. A diagnosis of acute urticaria or non-cold chronic inducible urticaria
2. Ongoing treatment with immunosuppressant drugs (corticosteroids, cyclosporine, azathioprine, methotrexate, omalizumab, dupilumab, sulfasala-zine, dapsone or others)
3. A positive test for pregnancy, HIV, Hepatitis B or Hepatitis C
4. Clinical laboratory values outside of the normal ranges at the Screening visit
5. History of any clinically significant abnormality that would contraindicate participation

There are additional criteria that your study doctor will review with you to confirm you are eligible for the study.

Results of safety (AEs, SAEs) will be made available.

Within 1 year after last subject last visit.