CDP571, a humanized antibody to human tumor necrosis factor-alpha

Abstract

To determine the safety of a "humanized" antibody to human anti-tumor necrosis factor-alpha (TNF-alpha) in patients with septic shock, and to examine the pharmacokinetics, immune response, and influence of the antibody on cytokine concentrations in this patient group. Prospective, randomized, placebo-controlled, phase II multicenter clinical trial, with escalating doses of a fully humanized anti-TNF-alpha antibody (CDP571). Seven academic intensive care units in Europe. Forty-two patients with rapidly evolving septic shock who received CDP571 in addition to standard supportive care. Patients received intravenously either placebo or one of four single doses of CDP571: 0.1, 0.3, 1.0, or 3.0 mg/kg. The humanized anti-TNF-alpha antibody was well tolerated. The overall all-cause 28-day mortality rate was 62%. Mortality rate was similar in the placebo and treatment groups, except that all six patients who received 0.3 mg/kg of CDP571 died within 7 days. This outcome, which was not dose-related, is consistent with the poorer prognostic characteristics of this group at baseline. The peak CDP571 concentrations and area under the curve increased proportionately with the dose. The low level of the immune response detected had little effect on the ability of circulating CDP571 to bind TNF-alpha and on the pharmacokinetics of the antibody. An abrupt reduction in circulating TNF-alpha concentration was observed 30 mins after CDP571 administration at all active dosage levels. While interleukin-1 beta and interleukin-6 plasma concentrations decreased with time in all dosage groups, these cytokine concentrations decreased more rapidly during the initial 24 hrs in the treatment groups than in the placebo group. The humanized anti-TNF-alpha antibody, CDP571, is well tolerated and able to cause a dose-dependent reduction in circulating TNF-alpha concentrations in patients with septic shock. Further studies are needed to determine the efficacy of this antibody to improve the survival rates of critically ill patients with severe sepsis.