Repeated administration of a F(ab')2 fragment of an anti-tumor necrosis factor alpha monoclonal antibody in patients with severe sepsis: effects on the cardiovascular system and cytokine levels.

In an uncontrolled clinical trial the effects of repeated administration of the F(ab')2 fragment of a murine monoclonal anti-tumor necrosis factor alpha (TNF alpha)-antibody (MAK 195F) on cytokine levels and the cardiovascular system were studied in 20 patients with severe sepsis. Patients were treated with a total of 11 single dosages of the anti-TNF alpha-antibody intravenously over 5 days using either 1 mg/kg (n = 10) or 3 mg/kg (n = 10). The anti-TNF alpha-antibody was well tolerated in all patients without signs of toxicity and without development of anti-murine antibodies. As assessed by cytokine levels (TNF alpha, Interleukin-6) and hemodynamics there was no evidence that the higher dosage of the anti-TNF alpha-antibody (3 mg/kg per dose) was more effective than the lower dosage (1 mg/kg per dose). Comparison of our data with recent data from phase I or II trials using a complete murine monoclonal anti-TNF alpha-antibody suggest that the F(ab')2 fragments of the murine monoclonal anti-TNF alpha-antibody may be of similar efficacy. Definitive conclusions, however, with respect to improvement of mortality and improvement of the cardiovascular system, await the results of larger ongoing placebo-controlled trials.