Discovery of Novel Orally Bioavailable Oxaborole 6-Carboxamides That Demonstrate Cure in a Murine Model of Late-Stage Central Nervous System African Trypanosomiasis

作者:Nare Bakela*; Wring Stephen; Bacchi Cyrus; Beaudet Beth; Bowling Tana; Brun Reto; Chen Daitao; Ding Charles; Freund Yvonne; Gaukel Eric; Hussain Ali; Jarnagin Kurt; Jenks Matthew; Kaiser Marcel; Mercer Luke; Mejia Elena; Noe Andy; Orr Matt; Parham Robin; Plattner Jacob; Randolph Ryan; Rattendi Donna; Rewerts Cindy; Sligar Jessica; Yarlett Nigel; Don Robert; Jacobs Robert
来源:Antimicrobial Agents and Chemotherapy, 2010, 54(10): 4379-4388.
DOI:10.1128/AAC.00498-10

摘要

We report the discovery of novel boron-containing molecules, exemplified by N-(1-hydroxy-1,3-dihydrobenzo[c] [ 1,2]oxaborol-6-yl)-2-trifluoromethylbenzamide (AN3520) and 4-fluoro-N-(1-hydroxy-1,3-dihydrobenzo[c] [ 1,2]oxaborol-6-yl)-2-trifluoromethylbenzamide (SCYX-6759), as potent compounds against Trypanosoma brucei in vitro, including the two subspecies responsible for human disease T. b. rhodesiense and T. b. gambiense. These oxaborole carboxamides cured stage 1 (hemolymphatic) trypanosomiasis infection in mice when administered orally at 2.5 to 10 mg/kg of body weight for 4 consecutive days. In stage 2 disease (central nervous system [CNS] involvement), mice infected with T. b. brucei were cured when AN3520 or SCYX-6759 were administered intraperitoneally or orally (50 mg/kg) twice daily for 7 days. Oxaborole-treated animals did not exhibit gross signs of compound-related acute or subchronic toxicity. Metabolism and pharmacokinetic studies in several species, including nonhuman primates, demonstrate that both SCYX-6759 and AN3520 are low-clearance compounds. Both compounds were well absorbed following oral dosing in multiple species and also demonstrated the ability to cross the blood-brain barrier with no evidence of interaction with the P-glycoprotein transporter. Overall, SCYX-6759 demonstrated superior pharmacokinetics, and this was reflected in better efficacy against stage 2 disease in the mouse model. On the whole, oxaboroles demonstrate potent activity against all T. brucei subspecies, excellent physicochemical profiles, in vitro metabolic stability, a low potential for CYP450 inhibition, a lack of active efflux by the P-glycoprotein transporter, and high permeability. These properties strongly suggest that these novel chemical entities are suitable leads for the development of new and effective orally administered treatments for human African trypanosomiasis.

  • 出版日期2010-10