A diffusion chamber technique for detecting compounds with clinical prophylactic activity against Brugia pahangi.

A new technique for examining the clinical prophylactic activity of antifilarial agents against Brugia pahangi is described. Third stage larvae were confined within diffusion chambers before intraperitoneal implantation into jirds. Such larvae developed normally within the chambers for 14 days when compared with infections in which larvae were allowed to grow freely within the peritoneal cavity. After this time conditions inside the chambers deteriorated and larval growth was inhibited. Larval recoveries from diffusion chambers after 14 days were higher and more reproducible than from intraperitoneal infections. The activities of known antifilarial agents against larvae confined within chambers implanted into jirds were examined. The benzimidazoles were found to be extremely effective Flubendazole killed almost all larvae when administered at 5 x 25 mg/kg sc by day 9 after the final treatment. It is suggested that the test described has potential as a screen for detecting clinical prophylactic activity because of its reproducibility, low parasite requirement, ease of parasite recovery and relatively short result acquisition time.