Use of mycophenolate mofetil in patients with pediatric and adult primary nephrotic syndrome: information from a Japanese hospital claims database.

BACKGROUND: Current treatment for frequently relapsing, steroid-dependent, or steroid-resistant nephrotic syndrome focuses on immunosuppressive therapies. Although the clinical guideline suggests the use of mycophenolate mofetil (MMF), limited information is available on patients with primary nephrotic syndrome who receive off-label treatment with MMF in Japan. METHOD: The dose, treatment duration, previous treatment, and characteristics of primary nephrotic syndrome patients receiving MMF were investigated using data from a Japanese hospital claims database (April 2008-September 2021). RESULTS: Data on 424 primary nephrotic syndrome patients receiving MMF (146 patients < 18 years old; 278 patients ≥ 18 years old) were captured. The most common initial daily doses of MMF capsules (% of patients < 18 and ≥ 18 years old) were 1000 mg (31.9%, 36.8%), 1500 mg (16.0%, 23.8%), and 500 mg (23.6%, 17.3%), and the most common maximum daily doses were 1000 mg (43.8%, 32.9%), 1500 mg (23.6%, 28.9%), and 2000 mg (6.3%, 16.2%). Most patients (97.9%, 99.3%) were treated with a daily dose of 2000 mg or less. Among patients < 18 years old, the younger the patient, the lower the dose. MMF was used for more than 1 year in 30.8% of patients < 18 years old and in 28.8% of patients ≥ 18 years old. CONCLUSIONS: Our study suggested that off-label use of MMF for primary nephrotic syndrome has increased since 2012 in Japan. The dose of MMF used in patients with primary nephrotic syndrome was generally within the approved dose range for lupus nephritis and transplant-related diseases in Japan.

Use of mycophenolate mofetil for systemic sclerosis and systemic sclerosis-associated interstitial lung disease: Information from a Japanese hospital claims database.

OBJECTIVES: Limited information is available on patients with systemic sclerosis (SSc) or SSc-associated interstitial lung disease (SSc-ILD) receiving mycophenolate mofetil (MMF) in Japan. The dose, treatment duration, and patient characteristics of SSc and SSc-ILD patients receiving MMF were investigated. METHODS: We used data from a Japanese hospital claims database (2008-2020). RESULTS: Data on 486 SSc patients ≥18 years old receiving MMF were captured; 314 had SSc complicated with ILD. The most common initial daily doses were 1000 mg (SSc, 39.5%; SSc-ILD, 38.1%) and 500 mg (SSc, 36.6%; SSc-ILD, 34.6%). The most common maximum daily doses were 1000 mg (SSc, 33.3%; SSc-ILD, 34.9%), 1500 mg (SSc, 24.4%; SSc-ILD, 23.1%), and 2000 mg (SSc, 23.8%; SSc-ILD, 24.4%). Doses ranged from 250 to 3000 mg/day and were similar for SSc and SSc-ILD patients. Over 27% of patients received treatment for >1 year. There was a gradual decrease in steroid doses during MMF treatment. CONCLUSIONS: Our study suggests that the off-label use of MMF for SSc and SSc-ILD has been increasing annually since 2015 in Japan. The doses used in patients with SSc and SSc-ILD were similar to the approved doses of MMF for lupus nephritis in Japan.