Background:

IC50: 7.7 nM against the parasites

Canine babesiosis is a tick-borne disease caused by the intraerythrocytic apicomplexan parasites, Babesia gibsoni and B. canis. Clinical signs of B. gibsoni infection are anemia, fever, thrombocytopenia, splenomegaly, lymphadenopathy, and lethargy. Bruceine A, a natural quassinoid compound extracted from the Brucea javanica (L.) Merr. dried fruits, was reported to have antibabesial activity.

In vitro: Bruceine A inhibited the in-vitro Babesia gibsoni growth in canine erythrocytes at lower concentration compared with the antibabesial drug diminazene aceturate and killed the parasites within 24 hr at a concentration of 25 nM [1].

In vivo: Oral administration of bruceine A at a dosage of 6.4 mg/kg/day for 5 days resulted in no clinical findings in a dog. An untreated dog developed typical acute babesiosis symptoms including high fever, severe anemia, and complete loss of appetite and movement. However, the two bruceine A-treated dogs maintained their healthy conditions throughout the experimental period of 4 weeks [1].

Clinical trials: Currenlty there is no clinical data available.

Reference:
[1] Nakao R, Mizukami C, Kawamura Y, Subeki, Bawm S, Yamasaki M, Maede Y, Matsuura H, Nabeta K, Nonaka N, Oku Y, Katakura K.  Evaluation of efficacy of bruceine A, a natural quassinoid compound extracted from a medicinal plant, Brucea javanica, for canine babesiosis. J Vet Med Sci. 2009 Jan;71(1):33-41.