Chronic spontaneous urticaria (CSU) is a common disease with a significant proportion of patients that do not respond to standard therapy with antihistamines and optionally corticosteroids/immunosuppressants.
The IL-1β antagonist canakinumab is effective in cryopyrin associated periodic syndromes (CAPS) associated with urticarial symptoms and urticarial vasculitis, so it was suspected that it could also be effective in patients with CSU.
The effect of canakinumab was investigated in 20 patients with moderate to severe CSU in a 1:1 randomization to either canakinumab or placebo in a double-blind single-dose crossover design. The verum group received 150 mg canakinumab subcutaneously once at baseline. Patients who had received placebo were able to switch to canakinumab at week 4 if they did not improve. Primary endpoint was clinical UAS7 improvement at week 4 compared to baseline. Secondary endpoints were the clinical UAS7 improvement at week 8 and the clinical improvement measured by the physician score and DLQI at week 1, 2, 4, and 8.
At week 4 two patients with canakinumab and three with placebo met the primary endpoint so that canakinumab failed the significant superiority to the placebo (p=1.0). An inclusion of the patients who switched to canakinumab after four weeks did not alter the result. There was also no significant difference between the verum and placebo groups for all secondary endpoints. The therapy was well tolerated, and mild AEs were equally distributed between verum and placebo.
Due to this clinical trial with 20 patients, it must be assumed that canakinumab has no effect on lesions of CSU. In conclusion, this suggests that IL1β may not play a crucial role in pathology of CSU patients, unlike e.g. in hereditary fevers or urticarial vasculitis, where targeting IL 1 is a main treatment option. However, the good tolerability of canakinumab could be confirmed.

Copyright © 2020. Published by Elsevier Inc.