Effects of Child-Pugh B Cirrhosis on Pharmacokinetics of Tofogliflozin, a New Sodium-Glucose Co-Transporter (SGLT2) Inhibitor.

BACKGROUND: Tofogliflozin is a highly selective sodium-glucose co-transporter 2 (SGLT2) inhibitor. A mass balance study with combinations of microdoses revealed that tofogliflozin has high oral bioavailability (97.5%) and that tofogliflozin in circulation is eliminated primarily by metabolic pathways, with the liver playing a prominent role in elimination. OBJECTIVES: This study aimed to evaluate the effect of moderate hepatic impairment on the pharmacokinetics of tofogliflozin and on the pharmacodynamics (urinary glucose excretion [UGE]). METHODS: In an open-label, parallel-group study, 17 subjects (9 with moderate hepatic impairment [Child-Pugh Class B, score 7-9] and 8 healthy) received a single oral dose of 40 mg tofogliflozin. Plasma and urine concentrations of tofogliflozin were determined. Accumulated UGE, adverse events, and physiological and laboratory test data were monitored. RESULTS: Geometric mean ratio (GMR; geometric mean value for subjects with moderate hepatic impairment / geometric mean value for healthy subjects) of Cmax was 1.47 and GMR of AUCinf was 1.70. Moderate hepatic impairment had only a little effect on tmax and CLR but it prolonged MRT. The levels of cumulative UGE were similar between the 2 groups. No clinically significant adverse events, laboratory test values, or physiological test values were observed in any subject. CONCLUSIONS: Moderate hepatic impairment increased Cmax and AUCinf of tofogliflozin by 47% and 70%, respectively. This increase in tofogliflozin exposure did not increase UGE in hepatically impaired subjects. A single oral dose of 40 mg tofogliflozin was well tolerated, supporting dose adjustment is unnecessary even in moderately hepatically impaired subjects.

Pharmacokinetics and Pharmacodynamics of Tofogliflozin (a Selective SGLT2 Inhibitor) in Healthy Male Subjects.

Tofogliflozin is a selective oral inhibitor of sodium-glucose co-transporter 2 for treatment of type 2 diabetes mellitus. The pharmacokinetics, pharmacodynamics, and safety of tofogliflozin were investigated in healthy male subjects. Three studies were conducted: single-ascending dose study (10-640 mg) in 56 Japanese and 24 Caucasian subjects; multiple-ascending dose study (2.5-80 mg once daily for 7 days) in 24 Japanese subjects; and food-effect study (20-40 mg) in 30 Japanese subjects. Tofogliflozin was absorbed rapidly and eliminated from the systemic circulation with a t1/2 of 5-6 h. Exposure increased dose-proportionally up to 320 mg. Body weight-corrected exposure was similar between Japanese and Caucasian subjects. Urinary excretion of tofogliflozin ranged from 17.1 to 27.4% of dose. Tofogliflozin did not accumulate with once daily administration. Food intake decreased Cmax by approximately 30% but did not change AUC0-inf. Tofogliflozin caused dose-dependent daily urinary glucose excretion (UGE0-24h), but food intake condition at administration did not affect it. The exposure-response relationship between plasma average concentration of tofogliflozin (Cavg) and UGE0-24h fitted Emax model well. There were no serious adverse events leading to discontinuation or episodes of hypoglycemia. Single and multiple administration of tofogliflozin were generally well tolerated. Exposure to tofogliflozin was dose-proportional up to 320 mg and did not accumulate with multiple once-a-day administration. The model suggests more than 100 ng/mL Cavg corresponding to the dose of between 20 and 40 mg leads to almost maximum effect of tofogliflozin.