Infliximab therapy efficacy and persistence at a Canadian academic centre despite a change in access procedure

Abstract

Patients treated with infliximab at our centre through a special access programme (initiation group) had long-standing, treatment-resistant rheumatoid arthritis. The clinical experience for these patients may be different than that of patients initiating treatment after provincial government approval and cost coverage for all anti-tumour necrosis factor (anti-TNF) therapies became effective (contemporary group). We compared adverse events, drug survival and reasons for discontinuation in these two groups. A prospective cohort of patients treated with an anti-TNF therapy was assembled following the availability of infliximab in 2000. By protocol, patients are assessed for treatment response, discontinuation or switching of biologic agents and occurrence of adverse events. We report on 231 patients treated with infliximab therapy (680patient-years). Both groups had similar drug survival (median 2.2years) and rates of serious adverse events including infusion reactions (6.8 per 100patient-years) and serious infections (3.4per 100 patient-years). More patients in the initiation group discontinued infliximab for adverse events [39/139 (28%) vs. 15/92 (16%), p = 0.04] and developed drug-induced lupus [8/139 (6%) vs. 0%, p = 0.02]. Subsequent biologics were discontinued for the same reason as infliximab in only 12% (15/123) of cases. Patients treated with infliximab through a special access programme have comparable drug survival compared to a contemporary group, despite experiencing more adverse events. Only a minority of patients discontinuing infliximab due to the lack of effect or adverse events experience the same fate with subsequent anti-TNF agents.