What is the dose of rituximab (rituximab) using the 90-minute rapid infusion protocol for treatment of pemphigus vulgaris after the initial slow infusion?

Rituximab 90-Minute Rapid Infusion Protocol for Pemphigus Vulgaris

For pemphigus vulgaris treatment using the 90-minute rapid infusion protocol, administer rituximab at a dose of 1000 mg per infusion, with two infusions given 2 weeks apart (rheumatoid arthritis protocol), but only after the patient has safely tolerated the first infusion at the standard slow rate of 50 mg/hour. 1, 2

Dosing Protocol

• The British Association of Dermatologists recommends the rheumatoid arthritis protocol for rituximab in pemphigus vulgaris: 2 infusions of 1000 mg each, given 2 weeks apart 1
• The first rituximab infusion must always be administered at the standard slow rate (typically starting at 50 mg/hour) to ensure patient tolerability 2
• Subsequent infusions can be administered using the 90-minute rapid infusion protocol, but only after confirming the patient tolerated the first infusion without significant infusion-related reactions 2
• This rapid infusion protocol is more cost-effective than the lymphoma protocol (375 mg/m² weekly for 4 weeks) while maintaining similar efficacy 1

Administration Guidelines for Rapid Infusion

• For the 90-minute rapid infusion (for second and subsequent infusions only):
  • Administer 20% of the total dose (200 mg) in the first 30 minutes 3
  • Administer the remaining 80% (800 mg) over the next 60 minutes 3
  • Total infusion time: 90 minutes 3

Efficacy and Outcomes

• Rituximab with short-term prednisolone results in complete remission in 89% of pemphigus vulgaris patients at 2 years, compared to only 34% with prednisolone alone 1
• Clinical responses typically begin within 6 weeks of administration 1, 2
• Modified rheumatoid arthritis protocols for rituximab have shown effectiveness and safety in treating pemphigus vulgaris patients 3
• Studies show that relapse occurs in approximately 15-65% of patients, typically 13-17 months after rituximab administration 1, 2

Combination Therapy Considerations

• Adjuvant systemic immunosuppressive drugs can be continued with rituximab, but dose reduction should be considered to decrease infection risk 1
• In treatment-resistant cases, consider combining rituximab with immunoadsorption or intravenous immunoglobulin 2
• For patients with mild to moderate disease, two infusions of rituximab may be sufficient, while those with severe disease may benefit from three or more infusions 4, 5

Monitoring and Safety

• Monitor for infusion reactions during and after administration, particularly with the first infusion 2
• Assess for clinical improvement, which typically occurs within days, with complete healing expected within 3-8 weeks 2
• CD19-positive B lymphocyte levels decrease significantly by day 28 after rituximab treatment and remain low for approximately 6 months 6
• Serious adverse events are uncommon, but include potential for infections due to B-cell depletion 2, 6

Retreatment Considerations

• For relapses, retreatment with rituximab using the same protocol is effective and maintains safety profile 7
• Three or more infusions of rituximab may provide better outcomes than two infusions in terms of complete remission and lower relapse rates 4