Treatment of refractory blistering autoimmune diseases with mycophenolic acid

Immunosuppressive drugs are used as steroid-sparing agents in the management of blistering autoimmune diseases. Mycophenolic acid (MPA) is a relatively new adjuvant drug that selectively inhibits T and B lymphocyte proliferation by suppressing de novo purine synthesis.

To evaluate the efficacy of MPA in refractory blistering autoimmune diseases and the safety profile of a recent formulation, enteric-coated mycophenolate sodium (EC-MPS), in comparison with mycophenolate mofetil (MMF).

Twelve patients with various bullous dermatoses (three pemphigus vulgaris, one pemphigus herpetiformis, three bullous pemphigoid (BP), two cicatricial pemphigoid (CP) and three epidermolysis bullosa acquisita (EBA)) were enrolled in the study. In 10 cases, MPA was administered in combination with systemic corticosteroids, while in two patients with severe diabetes mellitus MPA was employed as monotherapy. The total time on MPA varied from 2 to 8 months. Four patients were given MMF (2,000 mg daily), seven received EC-MPS (1,440 mg daily) and one received both sequentially.

Complete remission, lasting for a mean time of 6.1 months, was achieved in 10 patients. Partial remission was obtained in two patients with disseminated CP and EBA. Both MMF and EC-MPS were well tolerated, but the latter was better in terms of gastrointestinal adverse effects.

MPA may be proposed as a first-line adjuvant agent for pemphigus as well as for refractory BP and CP. MPA monotherapy has to be considered in selected cases of BP and pemphigus. The highly promising results obtained in EBA suggest a future key role for MPA in the management of this disease.