Nateglinide 60 Mg Oral Tablet

Hypoglycemia can happen suddenly and symptoms may differ in each individual and change over time in the same individual. Symptomatic awareness of hypoglycemia may be less pronounced in patients with longstanding diabetes, in patients with diabetic neuropathy (nerve disease), in patients using medications that block the sympathetic nervous system (e.g., beta-blockers) [see Drug Interactions (7)], or in patients who experience recurrent hypoglycemia.

Factors which may increase the risk of hypoglycemia include changes in meal pattern (e.g., macronutrient content), changes in level of physical activity, changes to coadministered medication [see Drug Interactions (7)], and concomitant use with other antidiabetic agents. Patients with renal or hepatic impairment may be at higher risk of hypoglycemia [see Use in Specific Populations (8.6, 8.7), Clinical Pharmacology (12.3)].

Patients should take nateglinide before meals and be instructed to skip the dose of nateglinide if a meal is skipped [see Dosage and Administration (2)]. Patients and caregivers must be educated to recognize and manage hypoglycemia. Self-monitoring of blood glucose plays an essential role in the prevention and management of hypoglycemia. In patients at higher risk for hypoglycemia and patients who have reduced symptomatic awareness of hypoglycemia, increased frequency of blood glucose monitoring is recommended.

The available data from published literature and the applicant's pharmacovigilance with use of nateglinide in pregnant women are insufficient to identify a drug-associated risk of major birth defects, miscarriage or other adverse maternal or fetal outcomes. There are risks to the mother and fetus associated with poorly controlled diabetes in pregnancy (see Clinical Considerations). Nateglinide should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. In animal reproduction studies, there was no teratogenicity in rats and rabbits administered oral nateglinide during organogenesis at approximately 27 and 8 times the maximum recommended human dose (MRHD), respectively, based on body surface area (BSA).

The estimated background risk of major birth defects is 6% to 10% in women with pre-gestational diabetes with a HbA1c > 7 and has been reported to be as high as 20% to 25% in women with a HbA1c > 10. The estimated background risk of miscarriage for the indicated population is unknown. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively.

Clinical Considerations

Disease-Associated Maternal and/or Embryo/Fetal Risk

Poorly controlled diabetes in pregnancy increases the maternal risk for diabetic ketoacidosis, pre-eclampsia, spontaneous abortions, preterm delivery, and delivery complications. Poorly controlled diabetes increases the fetal risk for major birth defects, stillbirth, and macrosomia related morbidity.

Data

Animal data

In embryofetal development studies, nateglinide administered orally during the period of organogenesis was not teratogenic in rats at doses up to 1,000 mg/kg (corresponding to 27 times the MRHD of 120 mg three times per day, based on BSA). In rabbits, embryonic development was adversely affected at 500 mg/kg/day and the incidence of gallbladder agenesis or small gallbladder was increased at a dose of 300 and 500 mg/kg (corresponding to 16 and 27 times the MRHD). No such effects were observed at 150 mg/kg/day (corresponding to 8 times the MRHD). In a pre- and postnatal development study in rats, nateglinide administered by oral gavage at doses of 100, 300, and 1000 mg/kg/day from gestation day 17 to lactation day 21 resulted in lower body weight in offspring of rats administered nateglinide at 1,000 mg/kg/day (corresponding to 27 times the MHRD).

There are no data on the presence of nateglinide in human milk, the effects on the breastfeeding infant, or the effects on milk production. The drug is present in animal milk. When a drug is present in animal milk, it is likely that the drug will be present in human milk (see Data). Because the potential for hypoglycemia in breast-fed infants, advise women that use of nateglinide is not recommended while breastfeeding.

Data

In rat reproduction studies, nateglinide and its metabolite are excreted in the milk following oral dose (300 mg/kg).  The overall milk: plasma (M/P) concentration ratio of the total radioactivity was approximately 1.4 based on AUC_0-48 values. The M/P ratio of unchanged nateglinide was approximately 2.2.

Absorption

Absolute bioavailability of nateglinide is approximately 73%. Plasma profiles are characterized by multiple plasma concentration peaks when nateglinide is administered under fasting conditions. This effect is diminished when nateglinide is taken prior to a meal. Following oral administration immediately prior to a meal, the mean peak plasma nateglinide concentrations (C_max) generally occur within 1 hour (T_max) after dosing. T_max is independent of dose.

The pharmacokinetics of nateglinide are not affected by the composition of a meal (high protein, fat, or carbohydrate). However, peak plasma levels are significantly reduced when nateglinide is administered 10 minutes prior to a liquid meal as compared to solid meal. When given with or after meals, the extent of nateglinide absorption (AUC) remains unaffected. However, there is a delay in the rate of absorption characterized by a decrease in C_max and a delay in time to peak plasma concentration (T_max).

Nateglinide did not have any effect on gastric emptying in healthy subjects as assessed by acetaminophen testing.

Distribution

Following intravenous (IV) administration of nateglinide, the steady-state volume of distribution of nateglinide is estimated to be approximately 10 L in healthy subjects. Nateglinide is extensively bound (98%) to serum proteins, primarily serum albumin, and to a lesser extent α₁ acid glycoprotein. The extent of serum protein binding is independent of drug concentration over the test range of 0.1 to 10 mcg/mL.

Elimination

In healthy volunteers and patients with type 2 diabetes mellitus, nateglinide plasma concentrations declined with an average elimination half-life of approximately 1.5 hours.

Metabolism

In vitro drug metabolism studies indicate that nateglinide is predominantly metabolized by the cytochrome P450 isozyme CYP2C9 (70%) and to a lesser extent CYP3A4 (30%).

The major routes of metabolism are hydroxylation followed by glucuronide conjugation. The major metabolites are less potent antidiabetic agents than nateglinide. The isoprene minor metabolite possesses potency similar to that of the parent compound nateglinide.

Excretion

Nateglinide and its metabolites are rapidly and completely eliminated following oral administration. Eighty-three percent of the 14^C-nateglinide was excreted in the urine with an additional 10% eliminated in the feces. Approximately 16% of the 14^C-nateglinide was excreted in the urine as parent compound.

Specific Populations

Renal Impairment

No pharmacokinetic data are available in subjects with mild renal impairment (CrCl 60 to 89 mL/min). Compared to healthy matched subjects, patients with type 2 diabetes mellitus and moderate and severe renal impairment (CrCl 15-50 mL/min) not on dialysis displayed similar apparent clearance, AUC, and C_max. Patients with type 2 diabetes and renal failure on dialysis exhibited reduced overall drug exposure (C_max decreased by 49%; not statistically significant). However, hemodialysis patients also experienced reductions in plasma protein binding compared to the matched healthy volunteers.

In a cohort of 8 patients with type 2 diabetes and end-stage renal disease (ESRD) (eGFR < 15 mL/min/1.73m²) M1 metabolite accumulation up to 1.2 ng/mL occurred with a dosage of 90 mg once daily for 1 to 3 months. In another cohort of 8 patients with type 2 diabetes on hemodialysis, M1 concentration decreased after a single session of hemodialysis. Although the hypoglycemic activity of the M1 metabolite is approximately 5 times lower than nateglinide, metabolite accumulation may increase the hypoglycemic effect of the administered dose.

Hepatic Impairment

In patients with mild hepatic impairment, the mean increase in C_max and AUC of nateglinide were 37% and 30% respectively, as compared to healthy matched control subjects. There is no data on pharmacokinetics of nateglinide in patients with moderate-to-severe hepatic impairment.

Gender

No clinically significant differences in nateglinide pharmacokinetics were observed between men and women.

Race

Results of a population pharmacokinetic analysis including subjects of Caucasian, Black, and other ethnic origins suggest that race has little influence on the pharmacokinetics of nateglinide.

Age

Age does not influence the pharmacokinetic properties of nateglinide.

Drug Interactions:

In vitro assessment of drug interactions

Nateglinide is a potential inhibitor of the CYP2C9 isoenzyme in vivo as indicated by its ability to inhibit the in vitro metabolism of tolbutamide. Inhibition of CYP3A4 metabolic reactions was not detected in in vitro experiments.

In vitro displacement studies with highly protein-bound drugs such as furosemide, propranolol, captopril, nicardipine, pravastatin, glyburide, warfarin, phenytoin, acetylsalicylic acid, tolbutamide, and metformin showed no influence on the extent of nateglinide protein binding. Similarly, nateglinide had no influence on the serum protein binding of propranolol, glyburide, nicardipine, warfarin, phenytoin, acetylsalicylic acid, and tolbutamide in vitro. However, prudent evaluation of individual cases is warranted in the clinical setting.

In vivo assessment of drug interactions

The effect of coadministered drugs on the pharmacokinetics of nateglinide and the effect of nateglinide on pharmacokinetics of coadministered drugs are shown in Tables 3 and 4. No clinically relevant change in pharmacokinetic parameters of either agent was reported when nateglinide was coadministered with glyburide, metformin, digoxin, warfarin, and diclofenac.

Mutagenesis: Nateglinide was not genotoxic in the in vitro Ames test, mouse lymphoma assay, chromosome aberration assay or in the in vivo mouse micronucleus test.

Impairment of Fertility: Fertility was unaffected by administration of nateglinide to rats at doses up to 600 mg/kg (corresponding to 16 times the MRHD of 120 mg three times per day, based on BSA).

At Week 24, treatment with nateglinide before meals resulted in statistically significant reductions in mean HbA1C and mean fasting plasma glucose (FPG) compared to placebo (see Table 5). The reductions in HbA1C and FPG were similar for patient's naïve to, and those previously exposed to, antidiabetic medications.

At Week 24, statistically significant reductions in mean HbA1c and FPG were observed with metformin monotherapy compared to nateglinide monotherapy, and the combination of nateglinide and metformin compared to either nateglinide or metformin monotherapy (see Table 7). 

Compared to placebo, nateglinide monotherapy was associated with a statistically significant increase in mean body weight, while no significant change in body weight was observed with metformin monotherapy or combination of nateglinide and metformin therapy (see Table 7). Among the subset of patients previously treated with other antidiabetic agents, primarily glyburide, HbA1C in the nateglinide monotherapy group increased slightly from baseline, whereas HbA1C was reduced in the metformin monotherapy group (see Table 7).