Treatment of severe chronic idiopathic urticaria with oral mycophenolate mofetil in patients not responding to antihistamines and/or corticosteroids.

BACKGROUND

Urticarial patients are usually treated with oral antihistamines and 50% respond well to this treatment; however, the other 50% do not respond to antihistamines and need a more aggressive approach, such as short or prolonged courses of oral corticosteroids or cyclosporine. Potential adverse effects, however, limit this regimen.

OBJECTIVE

To determine the efficacy of mycophenolate mofetil, an immunomodulatory drug, in the treatment of patients with severe chronic urticaria.

METHODS

In an open-label, uncontrolled trial, nine patients with documented chronic urticaria who had been treated previously with antihistamines and/or corticosteroids with poor response were enrolled in the trial. After 2 weeks of baseline assessment, patients received 1000 mg twice daily of mycophenolate mofetil for 12 weeks. Improvement was monitored using the urticarial activity score, which is the sum of the wheal number score and itch severity score. Patients also recorded their daily need for other medications to control allergic symptoms.

RESULTS

There was a significant decrease in the urticarial activity score relative to the baseline assessment at the end of the study period (P < 0.001). All patients were able to stop prednisone on completion of the study. There was also a decrease in antihistamine dose, but this did not reach statistical significance. Treatment with mycophenolate mofetil was not associated with significant adverse effects.

CONCLUSIONS

Mycophenolate mofetil may be a valuable and safe treatment for patients with chronic urticaria who do not respond to antihistamines and/or corticosteroids, and who require aggressive treatment to control their disease symptoms. Further controlled clinical studies are needed to determine its value.