Schiffenbauer A, et al. - The safety and effectiveness of infliximab in patients with refractory dermatomyositis (DM) and polymyositis (PM) was researched in this study. It was concluded that the infliximab therapy for patients with refractory PM and DM was well tolerated and may benefit a subset of patients.

Methods

• For this study, they designed a randomized, double-blind, placebo-controlled trial.
• In a blinded manner, participants received infusions of either placebo or infliximab 5 mg/kg at 0, 2, 6 and 14 weeks.
• The primary outcome was a ≥15% Manual Muscle Strength (MMT) improvement at Week 16 compared to Week 0.
• The secondary outcome measures were improvement characterized by the International Myositis Assessment and Clinical Studies Group (IMACS) criteria.
• Responders in each arm had the choice of either continuing the same treatment or changing to the non-responder treatment for that study arm at 16 Week.
• Non-responders in the 5 mg/kg infliximab arm were increased to infliximab 7.5 mg/kg for week 22, 30, 38.
• Non-responders in the placebo arm at week 16 received infliximab 5 mg/kg at weeks 16, 18, 22, 30, 38.
• At Week 40, outcomes were reassessed.

Results

• They observed that total twelve subjects finished the study to week 16.
• Out of them, 6 subjects received infliximab treatment at the dose of 5 mg/kg with only one subject meeting the responder criteria at that dose.
• Of the remaining five subjects on infliximab, three crossed over to the infliximab 7.5 mg/kg dose.
• One of those three subjects responded.
• All six patients in the placebo arm crossed over to the 5 mg/kg dosing regimen after Week 16, and two of those responded to infliximab.