What is the recommended dosage and usage of Deflazacort (Deflazacort) for inflammatory and autoimmune conditions?

Deflazacort Dosing and Usage for Inflammatory and Autoimmune Conditions

For inflammatory and autoimmune conditions, deflazacort is dosed at approximately 0.9 mg/kg/day orally once daily, which is bioequivalent to prednisone 0.75 mg/kg/day, with a maximum daily dose of 36 mg. 1, 2

Primary Indication and Dosing

Deflazacort is FDA-approved specifically for Duchenne muscular dystrophy (DMD) in patients 5 years and older at 0.9 mg/kg/day. 2 For DMD patients, the dose should be rounded up to the nearest achievable dose using available tablet strengths (6 mg, 18 mg, 30 mg, 36 mg), with a maximum of 36 mg/day (equivalent to 40 kg body weight). 1, 2

Off-Label Use in Autoimmune Conditions

While deflazacort has been studied in various autoimmune conditions, the evidence base is more limited compared to prednisone:

Autoimmune Hepatitis

• In patients with autoimmune hepatitis maintained on prednisone, deflazacort 7.5 mg/day successfully sustained remission over 2 years with minimal ALT and IgG elevation. 1
• The conversion ratio used was 6 mg deflazacort for each 5 mg prednisone equivalent. 3

Rheumatoid Arthritis and Inflammatory Arthritis

• Deflazacort demonstrated equivalent efficacy to prednisone in both short-term (4-6 weeks) and longer-term (13-52 weeks) studies for rheumatoid arthritis. 4, 5
• The therapeutic potency is approximately 83% that of prednisone, supporting the 0.9 mg/kg deflazacort to 0.75 mg/kg prednisone equivalence. 5

Juvenile Chronic Arthritis

• Deflazacort was at least as effective as prednisone in children with juvenile chronic arthritis. 4

Thrombocytopenic Purpura

• For chronic idiopathic thrombocytopenic purpura, 6 mg deflazacort for each 5 mg prednisone equivalent maintained platelet counts and improved bleeding parameters over 54-263 days. 3

Key Advantages Over Prednisone

Deflazacort may be preferred when pre-existing weight gain or behavioral issues are present, as it causes less weight gain than prednisone. 1

Metabolic Benefits

• Less impact on calcium metabolism and bone density compared to prednisone. 4, 5
• Reduced effect on growth rate in children requiring corticosteroid therapy. 4, 6
• No clinically relevant diabetogenic effects at moderate dosages over 2 months. 4
• Less acute inhibition of cortisol secretion compared to prednisone. 5

Bone Health Considerations

• Deflazacort appears to have less effect on parameters associated with corticosteroid-induced osteoporosis. 4
• However, annual DEXA scans, vitamin D monitoring, and calcium supplementation remain necessary. 1

Important Caveats and Monitoring

Cataracts

• Annual ophthalmological examination is required, as deflazacort may cause cataracts that affect vision. 1
• If vision-affecting cataracts develop, consider switching from deflazacort to prednisone. 1

Immunosuppression Risk

• Deflazacort may have greater immunosuppressive activity than previously recognized, potentially increasing risk of opportunistic infections. 7
• Complete all immunizations, particularly live vaccines, at least 4-6 weeks before starting deflazacort. 2

Drug Interactions

• Reduce deflazacort dose to one-third (e.g., 36 mg to 12 mg daily) when co-administered with moderate or strong CYP3A4 inhibitors. 2
• Avoid concurrent use with moderate or strong CYP3A4 inducers. 2
• Do not administer with grapefruit juice. 2

Standard Corticosteroid Monitoring

All patients require monitoring for: 1

• Hypertension (blood pressure at each visit)
• Glucose intolerance (urine dipstick at visits)
• Gastroesophageal reflux disease (consider ranitidine or proton-pump inhibitor if symptomatic)
• Bone demineralization (annual DEXA, vitamin D levels)
• Adrenal insufficiency (especially during dose reduction or withdrawal)

Discontinuation Protocol

Deflazacort must be tapered gradually if administered for more than a few days to prevent adrenal insufficiency. 2

For DMD patients with intolerable side effects: 1

• Reduce daily dosage by 25-33% and reassess in 1 month
• If still intolerable, consider additional 25% reduction
• Minimum effective daily dose of deflazacort equivalent is approximately 0.36 mg/kg/day (equivalent to prednisone 0.3 mg/kg/day)

Administration

• Can be taken with or without food 2
• Tablets can be administered whole or crushed and mixed immediately with applesauce 2

Cost Consideration

The prohibitive cost of deflazacort limits its widespread use, particularly in pediatric populations where data demonstrating superiority over conventional steroids remain limited. 6 Therefore, deflazacort should be reserved for adults predisposed to or developing intolerable metabolic sequelae with conventional corticosteroids, or for children where adverse effects of standard corticosteroids are particularly debilitating. 4