Abstract 229: Correlation of in vitro Studies and Human Drug Interaction Studies with Gemcabene

Background: Gemcabene is a novel lipid-regulating compound being developed as an adjunct to diet and statin therapy for dyslipidemia treatment. Patients with dyslipidemia typically take many medications often including statins and it is essential to understand potential risk of drug-drug interactions (DDI) to minimize the risk of adverse drug reactions. In the best circumstances, drugs entering the market will provide metabolic or transport pathways that do not interfere with commonly co-administered drugs. The current studies provide the analysis of potential drug interactions with gemcabene both in vitro and in vivo . Methods: Caco-2 cells were used to assess the potential P-gp substrate and inhibitor interaction and the major drug-metabolizing CYP450 isozymes and FMO-3 were used to assess the potential CYP450 and FM0-3 metabolism interaction. The results from the in vitro P-gp and CYP450 studies was correlated with the results of three DDI clinical studies with digoxin, atorvastatin and simvastatin. Results: In an open-label, multiple-dose study in 12 healthy subjects, gemcabene (900 mg) did not significantly affect the exposure (Cmax and AUC 0-24 ) of digoxin (0.25 mg). Specifically, the 90% confidence interval for digoxin AUC (0-24) ratios were within the 80% to 125% range, thus confirming the in vitro results of no DDI with a P-gp substrate. In two open-label, multiple-dose studies in healthy volunteers, gemcabene (900 mg) did not significantly affect the exposure (Cmax and AUC 0-24 ) of atorvastatin (80 mg) or simvastatin (80 mg) thus confirming the in vitro results of no DDI with CYP450 (see Figure below). Conclusion: These results suggest gemcabene is unlikely to elicit a metabolic (i.e., CYP450 or FMO3) or P-gp-mediated drug interaction. Gemcabene (900 mg) was well-tolerated in combination with highest dose of atorvastatin and simvastatin. Clinical Implications: Understanding potential for drug interactions minimizes the risk of adverse drug reactions.