Combination Therapy of Leflunomide and Glucocorticoids for the Maintenance of Remission in Patients with IgG4-related Disease: a Retrospective Study and Literature Review

Background: Although glucocorticoids are effective in IgG4-related disease (IgG4-RD), patients may relapse during or after glucocorticoid tapering. Immunosuppressive agents, including leflunomide (LEF), are regarded as steroid-sparing agents in other autoimmune disorders and need to be discussed in the management of IgG4-RD.

Aim: To identify the efficacy and safety of combination therapy of LEF and glucocorticoids in IgG4-RD.

Methods: We retrospectively summarised data of patients diagnosed with IgG4-RD between November 2012 and November 2015. Only patients treated with LEF plus glucocorticoids and had been followed up for more than three visits and 6 months were analysed with clinical symptoms, laboratory and imaging findings, treatment protocol, LEF-related adverse events and disease activity reflected by IgG4-RD Responder Index (IgG4-RD RI).

Results: A total of 18 patients, including 14 untreated patients and 4 relapsing patients, was included. The mean (SD) onset age was 54.0 (9.6) years. The mean (SD) follow-up period was 12.1 (7.4) months. All patients had active disease with mean (SD) IgG4-RD RI of 15.0 (5.6) at baseline and experienced improvements at 1 month. At the last follow up, the mean (SD) IgG4-RD Responder Index declined to 3.1 (1.7) in all patients and to 2.5 (1.2) in patients without relapse. The mean (SD) dose of GC declined to 6.9 (2.7) mg/day. A total of 12 (66.7%) and 11 (61.1%) patients were in remission at 6 months and the last follow up respectively. Three (16.7%) patients relapsed in clinical course. Two reversible adverse events were observed.

Conclusion: The combination therapy of LEF and glucocoticoids is effective and safe in IgG4-RD.