Pipobroman therapy of essential thrombocythemia.

We report our results with pipobroman (PB) therapy in patients with essential thrombocythemia (ET). 21 consecutive untreated patients were treated with PB from 1975 to 1984. PB was given at a dose of 1 mg/kg/d until platelet count dropped below 600 X 10(9)/l. In 18 patients (86%) a hematological remission was obtained. Median duration of induction phase was 49 d. In all cases a maintenance regimen was required at a dose ranging from 0.2 mg/kg/d to 0.5 mg/kg/d, according to platelet number. Follow-up of responder patients ranged from 6 to 108 months (median 17 months). Treatment was well tolerated and we observed only a very moderate and transient hematological toxicity. No patient had relapsed or developed secondary neoplasms at the time of writing. Median survival time of all patients was 24 months (range 10-115).