Activity of Chlorinated Lincomycin Analogues against Plasmodium Cynomolgi in Rhesus Monkeys

Kendall G. Powers Laboratory of Parasite Chemotherapy, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20014

Search for other papers by Kendall G. Powers in
Current site
Google Scholar
Restricted access

Three 7-chlorinated lincomycin derivatives exhibited curative activity against blood-inoculated Plasmodium cynomolgi infection in rhesus monkeys. Acute infections were treated by oral or subcutaneous administration for 5 consecutive days with doses ranging from 6.25 to 100 mg per kg body weight. Cures were obtained when U-21,251F (7-chlorolincomycin) and U-24,729A (7-chloro N-demethyl-4′-pentyllincomycin) were given orally at 50 mg per kg and when U-26,285A (7-chloro N-demethyllincomycin) was given at 100 mg per kg. U-24,729A and U-26,285A were also curative when given subcutaneously at 25 and 50 mg per kg, respectively. With all dosage regimens the blood was cleared of parasites 3 to 6 days after cessation of treatment. The rate of clearance of parasites did not appear to be related to dose. No side-effects due to the antibiotics were observed.