Discovery of 2-((R)-4-(2-Fluoro-4-(methylsulfonyl)phenyl)-2-methylpiperazin-1-yl)-N-((1R,2s,3S,5S,7S)-5-hydroxyadamantan-2-yl)pyrimidine-4-carboxamide (SKI2852): A Highly Potent, Selective, and Orally Bioavailable Inhibitor of 11ß-Hydroxysteroid Dehydrogenase Type 1 (11ß-HSD1).

A series of picolinamide- and pyrimidine-4-carboxamide-based inhibitors of 11ß-hydroxysteroid dehydrogenase type 1 was synthesized and evaluated to optimize the lead compound 9. The combination of the replacement of a pyridine ring of 9 with a pyrimidine ring and the introduction of an additional fluorine substituent at the 2-position of the phenyl ring resulted in the discovery of a potent, selective, and orally bioavailable inhibitor, 18a (SKI2852), which demonstrated no CYP and PXR liabilities, excellent PK profiles across species, and highly potent and sustainable PD activity. Repeated oral administration of 18a significantly reduced blood glucose and HbA1c levels and improved the lipid profiles in ob/ob mice. Moreover, the HbA1c-lowering effect of metformin was synergistically enhanced in combination with 18a.

A potent and selective 11ß-hydroxysteroid dehydrogenase type 1 inhibitor, SKI2852, ameliorates metabolic syndrome in diabetic mice models.

11ß-Hydroxysteroid dehydrogenase type 1 (11ßHSD1) has been targeted for new drugs to treat type 2 diabetes and metabolic syndrome. In this study, we determined whether the inhibition of 11ßHSD1 with a new selective inhibitor, SKI2852, could improve lipid profiles, glucose levels, and insulin sensitivity in type 2 diabetic and obese conditions. SKI2852 showed a potent inhibition of cortisone to cortisol conversion for over 80% in both liver and adipose tissue ex vivo from orally administered C57BL/6 mice, and in vivo analysis results were consistent with this. Repeated oral administrations of SKI2852 in diet-induced obesity (DIO) and ob/ob mice revealed a partially beneficial effect of SKI2852 in improving levels of cholesterols, triglycerides, free fatty acids, postprandial glucose, and/or blood hemoglobinA1c. SKI2852 significantly reduced body weight increase in ob/ob mice, and efficiently suppressed hepatic mRNA levels of gluconeogenic enzymes in DIO mice. Moreover, SKI2852 enhanced hepatic and whole body insulin sensitivities in hyperinsulinemic-euglycemic clamp experiment in DIO mice. In conclusion, these results indicate that selective and potent inhibition of 11ßHSD1 by SKI2852, thus blockade of active glucocorticoid conversion, may improve many aspects of metabolic parameters in type 2 diabetes and metabolic diseases, mainly by inhibitions of hepatic gluconeogenesis and partial improvements of lipid profiles. Our study strongly support that SKI2852 may have a great potential as a novel candidate drug for the treatment of diabetes and metabolic diseases.

Ursodeoxycholic acid, an inhibitor of hepatocyte nuclear factor 1α, did not increase the systemic exposure of pitavastatin.

OBJECTIVE: Pitavastatin, a highly potent inhibitor of 3-hydroxy-methylglutarylcoenzyme A reductase, is a known substrate of OATP1B1. Ursodeoxycholic acid (UDCA) inhibits OATP1B1 expression by repressing hepatocyte nuclear factor 1α (HNF1α). Thus, the effects of UDCA on the pharmacokinetics of pitavastatin were investigated in healthy subjects. METHODS: An open-label, 2-phase, parallel study was conducted with 13 healthy volunteers. In the control phase, after an overnight fast, each subject received a single dose of 2 mg pitavastatin. After a 1-week washout period, in the UDCA phase, subjects received a daily oral dose of 600 mg of UDCA (300 mg b.i.d.) for 14 days. On day 15, 2 mg of pitavastatin was administered as described previously for the control phase. RESULTS: In the UDCA phase, the maximum plasma concentration (C(max)) of pitavastatin was slightly higher than in the control phase (48.6 ± 22.9 ng/mL vs. 42.4 ± 16.1 ng/mL). However, the overall pharmacokinetic parameters of pitavastatin and pitavastatin lactone during the two study phases were not significantly different. CONCLUSIONS: UDCA had no significant effect on the pharmacokinetics of pitavastatin. These results do not support the notion that UDCA increases the systemic exposure of OATP1B1 substrate by inhibiting HNF1α and decreasing OATP1B1 transporter expression.