Critical evaluation of taeniacidal antibiotic S15-1 (SQ 21, 704) for removal of natural tapeworm infections in dogs and cats.

The new taeniacidal antibiotic S15-1 (SQ 21,704) was evaluated against naturally occuring infections of Taenia pisiformis in 53 dogs, Dipylidium caninum in 35 dogs, T taeniaformis in 18 cats, and D caninum in 33 cats. It all instances, the compound was administered in gelatine capsules in a single oral dose. The doses tested were between and 200 mg/kg of body weight in dogs and between 15 and 45 mg/kg in cats. In dogs, doses of 25 mg/kg and greater were 100% effective against T pisiformis, whereas a dose of 50 mg/kg was necessary to clear D caninum. In cats, a single oral dose of 22.5 mg/kg was 100% efficacious against T taeniaeformis, and a single dose of 45 mg/kg (the largest dose tested) clearly seven of eight cats of D caninum. The efficacy was limited to tapeworms only; there was no efficacy against nematodes. The antibiotic was well tolerated by both species with no drug-related vomiting or other side-effects observed.