INTRAVENOUS PULSE ADMINISTRATION OF CYCLOPHOSPHAMIDE VERSUS DAILY ORAL TREATMENT IN PATIENTS WITH ANTINEUTROPHIL CYTOPLASMIC ANTIBODY-ASSOCIATED VASCULITIS AND RENAL INVOLVEMENT - A PROSPECTIVE, RANDOMIZED STUDY

Objective. There is growing concern about the toxic side effects of da ily oral cyclophosphamide (CYC) treatment. Intravenous (IV) pulse admi nistration of CYC has been shown to be effective in patients with syst emic lupus erythematosus, but contradictory results have been reported in patients with antineutrophil cytoplasmic antibody (ANCA)-associate d vasculitis, Methods. The efficacy and toxicity of TV pulse administr ation of CYC (0.75 gm/m(2)) versus daily oral CYC treatment (2 mg/kg b ody weight) mere investigated in a prospective, randomized, multicente r study in patients with ANCA-associated vasculitis and renal involvem ent, Results. The cumulative CYC dose was reduced by 57% in patients w ith IV pulse treatment (n = 22) compared with patients treated with da ily oral therapy (n = 25), Patient survival, remission rate, time of r emission, relapse rate, and outcome of renal function were not differe nt between the 2 treatment groups. However, the rate of leukopenia (P < 0.01) and severe infections (P < 0.05 by 1-tailed test) was signific antly reduced in the IV pulse group compared with the group receiving daily oral treatment, Moreover, gonadal toxicity was reduced in the IV pulse group, as indicated by significantly lower levels of follicle-s timulating hormone. Conclusion. This randomized study shows that IV CY C administration is an effective therapeutic tool with low toxicity in patients with ANCA-associated vasculitis and renal involvement.