What is the appropriate treatment and dosage of Actemra (tocilizumab) for a patient with rheumatoid arthritis or systemic juvenile idiopathic arthritis?

Actemra (Tocilizumab) Treatment and Dosing

Rheumatoid Arthritis

For adult patients with rheumatoid arthritis, start with intravenous tocilizumab 4 mg/kg every 4 weeks, escalating to 8 mg/kg every 4 weeks based on clinical response, or use subcutaneous tocilizumab 162 mg weekly for patients ≥100 kg or every other week for patients <100 kg (escalating to weekly as needed). 1

Intravenous Dosing for RA

• Initial dose: 4 mg/kg every 4 weeks 1
• Escalation: Increase to 8 mg/kg every 4 weeks based on clinical response 1, 2
• Maximum dose: Do not exceed 800 mg per infusion 1
• Administration: Dilute to 100 mL in 0.9% or 0.45% sodium chloride and infuse over 1 hour 1

Subcutaneous Dosing for RA

• Patients <100 kg: 162 mg every other week, escalate to weekly based on response 1
• Patients ≥100 kg: 162 mg weekly 1
• Can be used as monotherapy or with methotrexate and other non-biologic DMARDs 1, 2

Systemic Juvenile Idiopathic Arthritis (sJIA)

For systemic JIA, tocilizumab is recommended for patients with active joint count >0 following treatment with anakinra or methotrexate/leflunomide, using weight-based dosing. 3

Intravenous Dosing for sJIA

• Patients <30 kg: 12 mg/kg every 2 weeks 1
• Patients ≥30 kg: 8 mg/kg every 2 weeks 1
• Dilution for <30 kg: Dilute to 50 mL in 0.9% or 0.45% sodium chloride 1
• Dilution for ≥30 kg: Dilute to 100 mL in 0.9% or 0.45% sodium chloride 1

Subcutaneous Dosing for sJIA

• Patients <30 kg: 162 mg every 2 weeks 1
• Patients ≥30 kg: 162 mg every week 1

Treatment Algorithm for sJIA

• First-line options: NSAIDs, intraarticular glucocorticoids, or systemic glucocorticoids for patients with high disease activity 3
• Second-line: Initiate tocilizumab for active joint count >0 after anakinra (Level B evidence) or methotrexate/leflunomide (Level B evidence) 3
• Alternative: Tocilizumab is also recommended for patients with physician global assessment ≥5 despite prior NSAID monotherapy 3

Polyarticular Juvenile Idiopathic Arthritis (pJIA)

For polyarticular JIA, use tocilizumab after inadequate response to methotrexate, with weight-based dosing every 4 weeks intravenously or weight-based frequency subcutaneously. 3

Intravenous Dosing for pJIA

• Patients <30 kg: 10 mg/kg every 4 weeks 1
• Patients ≥30 kg: 8 mg/kg every 4 weeks 1

Subcutaneous Dosing for pJIA

• Patients <30 kg: 162 mg every 3 weeks 1
• Patients ≥30 kg: 162 mg every 2 weeks 1

Treatment Algorithm for pJIA

• Combination therapy with methotrexate is conditionally recommended over biologic monotherapy 3
• Tocilizumab is positioned after inadequate response to methotrexate or other conventional DMARDs 3

Critical Safety Monitoring and Dose Modifications

Pre-Treatment Requirements

• Do not initiate if: ANC <2000/mm³, platelets <100,000/mm³, or ALT/AST >1.5× ULN 1
• Screen for tuberculosis before starting treatment 3
• Hold treatment during active infections 1

Laboratory Monitoring and Dose Adjustments

For liver enzyme elevations (ALT/AST):

• 1-3× ULN: Reduce IV dose to 4 mg/kg or reduce SC frequency to every other week 1
• 3-5× ULN (confirmed): Hold until <3× ULN, then resume at reduced dose 1
• >5× ULN: Discontinue tocilizumab permanently 1

For neutropenia:

• ANC 500-1000/mm³: Hold dosing; resume at reduced dose when ANC >1000/mm³ 1
• ANC <500/mm³: Discontinue tocilizumab permanently 1

For thrombocytopenia:

• Platelets 50,000-100,000/mm³: Hold dosing; resume at reduced dose when platelets >100,000/mm³ 1
• Platelets <50,000/mm³: Discontinue tocilizumab permanently 1

Common Pitfalls to Avoid

• Do not use tocilizumab in patients with macrophage activation syndrome (MAS) without specific modifications; anakinra, calcineurin inhibitors, or systemic glucocorticoids are preferred initial options for MAS 3
• Do not continue NSAID or glucocorticoid monotherapy beyond 1-2 months in systemic JIA patients with persistent disease activity 3
• Do not administer as bolus or push; always infuse IV formulation over 1 hour 1
• Monitor for serious infections closely, as signs of acute inflammation may be suppressed 1, 4
• Avoid live vaccines during tocilizumab treatment 1