Controlled therapeutic trials of pentoxifylline in relapsing-experimental auto-immune encephalomyelitis.

This study was designed to assess the capacity of several doses of pentoxifylline to prevent or treat chronic-relapsing-EAE (CR-EAE) exacerbations induced in the Lewis rat. Pentoxifylline (PTX) is a methylxanthine derivative that inhibits the production of TNF-alpha, a cytokine involved in EAE and multiple sclerosis physiopathology. Three blind placebo-controlled randomized studies were performed in respectively 40, 30 and 18 rats: a trial of different (PTX) dosages (8, 30, 50, 100 and 200 mg/kg) versus placebo to prevent EAE onset; a trial of PTX (8, 30 or 50 mg/kg) versus placebo to prevent 2 attacks of EAE and a trial of PTX (100 mg/kg) versus placebo to abrogate ongoing clinical EAE. No statistically significant difference was observed between groups in any trial. PTX was ineffective to prevent or treat CR-EAE in these studies.