title: Hycanthone dose-response in treatment of schistosomiasis mansoni in St. Lucia.
abstract: Clinical trials of hycanthone (single intramuscular dose) were undertaken in schistosomiasis mansoni patients in St. Lucia at five dose levels: 3.0, 2.5, 2.0, 1.5, and 1.0 mg/kg body weight. The most common side effect, vomiting, decreased in frequency from 51% at the highest dose to 3% at the lowest; minor side effects showed a similar trend. Three fecal specimens were examined before and at 6 months after treatment by qualitative, quantitative, and hatching techniques. All dose levels caused reductions in egg excretion of 89 to 98%. Rates of cure (absence of eggs by all three methods) according to dose (descending), pretreatment egg output (0-19, 20-49, 50-399, 400+ eggs/ml feces), and age (0-7, 8-14, 15-29, 30+ years) were analyzed to estimate the effect of each variable if the others had been constant. For dose, the standardized percentage success rates were 53.9%, 62.0%, 51.2% 54.0%, and 27.4%; for egg output, 67.0%, 51.8%, 43.2%, and 21.7%; and for age, 25.2%, 34.5%, 59.3% and 57.4%. Logit regression analysis shows a significant difference in cure rate (a) between the lowest dose and all others, among which latter there was no difference, (b) between patients excreting 0 to 49 eggs/ml before treatment and those excreting 50+ eggs/ml, and (c) between the age groups 0 to 14 and 15+ years. All dose levels caused some regression in enlargement of liver or spleen. A dose of 1.5 to 2.0 mg/kg body weight is considered to be as effective as one of 3.0 mg/kg and more acceptable for a control program because of the marked reduction in side effects.
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D004305:Dose-Response Relationship, Drug; D005243:Feces / Q000469:parasitology; D005260:Female; D006801:Humans; D006826:Hycanthone / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use; D007223:Infant; D007273:Injections, Intramuscular; D008297:Male; D012550:Schistosoma mansoni; D012552:Schistosomiasis / Q000188:drug therapy* / Q000469:parasitology; D013892:Thioxanthenes / Q000008:administration & dosage*; D014900:West Indies
chemical_list: D013892:Thioxanthenes; D006826:Hycanthone