[Cyclophosphamide versus bolus in Wegener's granulomatosis and other ANCA-related vasculitides: advantages and disadvantages].

Cyclophosphamide remains the therapy of choice in severe ANCA positive vasculitis. In order to avoid the considerable side effects of high cumulative doses sometimes manifesting themselves years later, induction therapy with a low cyclophosphamide dose and an early switch to cyclophosphamide-free maintenance regimens should be aimed for. This can be achieved by an induction therapy of 3--6 months of intravenous pulse therapy (pCYC) or oral therapy (oCYC). The metaanalysis of therapeutic trials in ANCA vasculitis demonstrates a slightly higher induction rate of remission, but an increased relapse rate of pCYC compared to oCYC. The incidence of adverse events seems to be higher in oCYC compared to pCYC. The results of the first controlled prospective multicenter trial (CYCLOPS) directly comparing pCYC and oCYC treatment of ANCA-positive vasculitis are eagerly awaited. It will be important to extend the follow-up over several years in order to reach a valid estimate of the incidence of secondary malignancies due to CYC therapy.