Studies on depot antimalarials. I. The effect of a single injection of the depot antimalarial CI-501 ("Camolar") on relapsing vivax malaria acquired in New Guinea.

An intramuscular injection of 2-5 ml. (350 mgm.) of CI-501 (cycloguanil pamoate) was given to 24 patrol officers from the Territory of Papua and New Guinea after arriving in Sydney, in order to ascertain the duration of protection given by a single injection of this drug. It had already been found that if such officers cease taking their antimalarial drug after arriving in Sydney, about half of them develop vivax malaria during the year they spend in Australia.
The subjects were examined clinically, parasitologically, haematologically and biochemically before the injection of the drug. They were followed up daily for a week and thereafter blood films were examined monthly for 8 months and v/henever the subjects reported with fever, cold, influenza or headache. It was found that 11 of the 24 subjects in the study developed overt vivax malaria during the subsequent 8 months, and the main effect of the drug (Camolar) was merely to delay the appearance of overt vivax malaria for 3 months. Local reactions to the injection were seen in half the subjects and were mainly mild in nature.

Full text article: https://www.cabdirect.org/cabdirect/abstract/19672900757