Therapeutic properties of metrifonate.

The chronology of the clinical trials with metrifonate is described: the first phase where independently of Bayer use was made of the veterinary product, the second phase representing the work done in collaboration with WHO to confirm the correct indication (schistosomiasis due to S. haematobium) and dosage schedule, and the third phase as from 1970 on about the use of the product in large groups of patients. The particular aspects of schistosomiasis are discussed, as well as the place of chemotherapy in antischistosomal projects. In this conjunction the snail control measures are mentioned. Mass treatment is described and the question is raised whether repeated administrations at half-yearly or yearly intervals are of value in decreasing the total egg output, thus lowering the possibilities of reinfection.