Slow infusions of vinblastine in the treatment of adult idiopathic thrombocytopenic purpura: a report on 43 cases.

Forty-three adult patients with idiopathic thrombocytopenic purpura (ITP) were treated by slow intravenous infusions of vinblastine. Nineteen had ITP of recent onset (i.e. of less than 6 months duration) and had contraindication to steroids (3 patients), refractoriness to steroids (6 patients) or to steroids and high dose intravenous immunoglobulins (IVIg, 10 patients). Of the 19 patients, 10 achieved complete response (CR), 2 achieved partial response (PR), 2 had minor response (MR) and the remaining 5 patients had no response (NR). Six of the complete responders remained in CR after 12 to 48 months, whereas all other responders relapsed within 3 months, in spite of maintenance therapy. Twenty-four patients had chronic ITP (i.e. of 6 months duration or more) and had showed no or only transient response to steroids and/or splenectomy, and in many of them, to other therapeutic approaches. Four achieved CR, 4 PR, 6 MR and 10 NR. All but 3 responses were shorter than 3 months, in spite of maintenance therapy. Most responses to slow infusions of vinblastine began after the first infusion. Main side effects included leukopenia in 9 patients (but with absolute neutropenia in only one) and peripheral neuropathy in 2 patients. Interval from diagnosis was the only prognostic factor of response to treatment. We conclude that slow infusions of vinblastine may be a useful approach in ITP of recent onset, when contraindication or refractoriness to steroids and/or IVIg exists. In our experience, this treatment has limited benefit in chronic ITP. In addition, it remains to be demonstrated that slow infusions of vinca alkaloids have any superiority over intravenous bolus injections of the same drugs.