Incidence and Management of Infusion Reactions to Infliximab in a Prospective Real-Life Community Registry

Abstract

Infliximab (IFX) is a therapeutic monoclonal antibody targeting TNFα indicated in the treatment of a number of chronic inflammatory diseases. IFX is administered by intravenous infusion and may be associated with infusion reactions (IR). RemiTRAC Infusion is a prospective Canadian observational registry in which IFX infusions are followed to document the incidence and management of IR, pre-medication use and adverse events (AE). An IR was defined as any AE occurring during the infusion or within 1 hour post infusion. Since its inception in 2005, 1398 patients have been enrolled and 18,121 infusions were recorded. There were 253 Crohn's disease patients (16%) and 80 UC patients (6%). The majority of remaining patients (64%) were treated for rheumatologic conditions. A total of 181/1398 patients reported at least one IR (13%). Only 292/18,121 infusions resulted in an IR (1.6%) and most IRs were mild to moderate in severity (94%). The most common infusion AE was pruritus which occurred in 14.2% of IR. Flushing (9.9%), urticaria (9.2%), nausea (6.3%) dyspnoea (6.0%) and chest discomfort (5.0%) were the only other infusion AEs occurring in ≥5% of IR. Pre-medication, which included anti-histamines, intravenous steroids and/or acetaminophen, was used in 42% of infusions and 1.8% of them were associated with an IR. Interestingly, infusions without any pre-medication were associated with a 1.4% incidence of IR. Infusions pre-medicated with anti-histamines, either alone or in combination with steroids, were associated with a significantly higher incidence of IR, up to 3.3% in the presence of anti-histamines (P < 0.0001) and up to 5.3% in the presence of anti-histamines and steroids (P < 0.0001). In contrast, only acetaminophen pre-medication was associated with a reduced incidence of IR (0.8%, P < 0.0001). We noted that infusions immediately following an IR were associated with a 31% incidence of a subsequent IR (44/140) despite the prevalent use of prophylactic pre-medication. This likely explains the higher incidence of IR in the presence of anti-histamines and/or steroids. This registry shows that, in community-based infusion clinics, infusion reactions to IFX are rare in incidence and largely mild to moderate in nature. Only the use of acetaminophen pre-medication was associated with a lower incidence of IR.