Objective: Biological products that neutralize tumour necrosis factor alpha (TNF-alpha) are beneficial in rheumatoid arthritis (RA). We studied the effects of CDP870, a novel anti-TNF-alpha antibody fragment modified to obtain a prolonged plasma half-life ( approximately 14 days).
Methods: Thirty-six patients were randomized in a double-blind, ascending-dose group study to a single intravenous infusion of placebo (n = 12) or 1, 5 or 20 mg/kg CDP870 (each n = 8). The patients were predominantly female (30/36), had a mean age of 56 yr and a mean duration of RA of 13 years. They had received a mean of five DMARDs or experimental therapies (with 1 month washout before the study started) and had active disease. Continuation of NSAIDs and up to 7.5 mg prednisolone daily was allowed. Following the blinded dosing period, 32 patients received a single open-label infusion of either 5 or 20 mg/kg CDP870.
Results: In the blinded dosing period, 6/12 placebo patients withdrew from the study (for deteriorating RA < or =4 weeks after dosing). Two of 24 CDP870-treated patients withdrew, both in the 1 mg/kg group (for deteriorating RA or lost to follow up >4 weeks after dosing). The proportion of patients with ACR20 improvement for the per-protocol population with the last observation carried forward was 16.7, 50, 87.5 and 62.5% after 0, 1, 5 and 20 mg/kg CDP870 respectively (combined treatment effect, P = 0.012, primary analysis) at 4 weeks and 16.7, 25, 75 and 75% (P = 0.032) at 8 weeks. The proportion of patients with ACR50 improvement for the per-protocol population with the last observation carried forward was 0, 12.5, 12.5 and 50% after 0, 1, 5 and 20 mg/kg CDP870 respectively (combined treatment effect, P = 0.079) at 4 weeks and 0, 12.5, 12.5 and 50% (P = 0.079) at 8 weeks. Following the open-label dose of CDP870, similar beneficial effects were achieved.
Conclusion: CDP870 is effective, was very well tolerated in this small study, and has an extended duration of action following one or more intravenous doses.