Efficacy of a new Hoffmann-La Roche compound (Ro 15-5458) against Schistosoma mansoni (Gezira strain, Sudan) in vervet monkeys (Cercopithecus aethiops).

Some compounds of the class 9-acridanone-hydrazones have recently been developed by Hoffmann-La Roche (Basel-Switzerland) and were shown to have antischistosomal effects. One of these compounds (RO 15-5458/000) was administered at two dose levels (25 mg and 15 mg/kg body-weight) to S. mansoni (Gezira strain-Sudan) infected vervet monkeys. The faecal egg-output was terminated, worm-burden killed and tissue egg-counts were greatly reduced as compared with the untreated control monkey. Severe necrotic changes were seen around dead worms in sections from treated animals' livers. The efficacy of this compound as an antischistosomal is encouraging and deserves further studying.