JANUMET

JANUMET (sitagliptin and metformin HCl) tablets for oral use contain two antihyperglycemic drugs: sitagliptin and metformin HCl. Sitagliptin Sitagliptin is an orally-active inhibitor of the dipeptidyl peptidase-4 (DPP-4) enzyme. Sitagliptin is present in JANUMET tablets in the form of sitagliptin phosphate monohydrate. Sitagliptin phosphate monohydrate is described chemically as 7-[(3 R )-3-amino-1-oxo-4-(2,4,5-trifluorophenyl)butyl]-5,6,7,8-tetrahydro-3-(trifluoromethyl)-1,2,4-triazolo[4,3- a ]pyrazine phosphate (1:1) monohydrate with an empirical formula of C 16 H 15 F 6 N 5 O∙H 3 PO 4 ∙H 2 O and a molecular weight of 523.32. The structural formula is: Sitagliptin phosphate monohydrate is a white to off-white, crystalline, non-hygroscopic powder. It is soluble in water and N,N-dimethyl formamide; slightly soluble in methanol; very slightly soluble in ethanol, acetone, and acetonitrile; and insoluble in isopropanol and isopropyl acetate. sitagliptin chemical structure Metformin HCl Metformin HCl ( N , N -dimethylimidodicarbonimidic diamide hydrochloride) is not chemically or pharmacologically related to any other classes of oral antihyperglycemic agents. Metformin HCl is a white to off-white crystalline compound with a molecular formula of C 4 H 11 N 5 ∙HCl and a molecular weight of 165.63. Metformin HCl is freely soluble in water and is practically insoluble in acetone, ether, and chloroform. The pK a of metformin HCl is 12.4. The pH of a 1% aqueous solution of metformin HCl is 6.68. The structural formula is as shown: metformin hydrochloride chemical structure JANUMET JANUMET is available as film-coated tablets containing: 64.25 mg sitagliptin monohydrate equivalent to 50 mg of sitagliptin and 389.93 mg of metformin equivalent to 500 mg metformin HCl (JANUMET 50/500). 64.25 mg sitagliptin monohydrate equivalent to 50 mg of sitagliptin and 779.86 mg of metformin equivalent to 1000 mg metformin HCl (JANUMET 50/1000). Each film-coated tablet of JANUMET contains the following inactive ingredients: microcrystalline cellulose, polyvinylpyrrolidone, sodium lauryl sulfate, and sodium stearyl fumarate. In addition, the film coating contains the following inactive ingredients: polyvinyl alcohol, polyethylene glycol, talc, titanium dioxide, red iron oxide, and black iron oxide.

JANUMET is indicated as an adjunct to diet and exercise to improve glycemic control in adults with type 2 diabetes mellitus. Limitations of Use JANUMET should not be used in patients with type 1 diabetes mellitus. JANUMET has not been studied in patients with a history of pancreatitis. It is unknown whether patients with a history of pancreatitis are at increased risk for the development of pancreatitis while using JANUMET. [See Warnings and Precautions (5.2) .] JANUMET is a combination of sitagliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor, and metformin hydrochloride (HCl), a biguanide, indicated as an adjunct to diet and exercise to improve glycemic control in adults with type 2 diabetes mellitus. ( 1 ) Limitations of Use: JANUMET should not be used in patients with type 1 diabetes. ( 1 ) JANUMET has not been studied in patients with a history of pancreatitis. ( 1 , 5.2 )

Take JANUMET orally twice daily with meals. ( 2.1 ) Individualize the dosage of JANUMET on the basis of the patient’s current regimen, effectiveness, and tolerability. ( 2.1 ) The maximum recommended daily dose is 100 mg of sitagliptin and 2000 mg of metformin HCl. ( 2.1 ) The recommended starting dose in patients not currently treated with metformin is 50 mg sitagliptin and 500 mg metformin HCl twice daily, with gradual dose escalation recommended to reduce gastrointestinal side effects associated with metformin. ( 2.1 ) The starting dose in patients already treated with metformin should provide sitagliptin dosed as 50 mg twice daily (100 mg total daily dose) and the dose of metformin already being taken. For patients taking metformin HCl 850 mg twice daily, the recommended starting dose of JANUMET is 50 mg sitagliptin and 1000 mg metformin HCl twice daily. ( 2.1 ) Prior to initiation, assess renal function with estimated glomerular filtration rate (eGFR) ( 2.2 ) Do not use in patients with eGFR below 30 mL/min/1.73 m 2 . JANUMET is not recommended in patients with eGFR between 30 and less than 45 mL/min/1.73 m 2 . JANUMET may need to be discontinued at time of, or prior to, iodinated contrast imaging procedures. ( 2.3 ) 2.1 Recommended Dosing Take JANUMET orally twice daily with meals. Individualize the dosage of JANUMET on the basis of the patient’s current regimen, effectiveness, and tolerability. The maximum recommended daily dose is 100 mg of sitagliptin and 2000 mg of metformin hydrochloride (HCl). Do not split or divide JANUMET tablets. The recommended starting dose in patients not currently treated with metformin is 50 mg sitagliptin and 500 mg metformin HCl twice daily, with gradual dose escalation recommended to reduce gastrointestinal side effects associated with metformin. The starting dose in patients already treated with metformin should provide sitagliptin dosed as 50 mg twice daily (100 mg total daily dose) and the dose of metformin already being taken. For patients taking metformin HCl 850 mg twice daily, the recommended starting dose of JANUMET is 50 mg sitagliptin and 1000 mg metformin HCl twice daily. 2.2 Recommendations for Use in Renal Impairment Assess renal function prior to initiation of JANUMET and periodically thereafter. JANUMET is contraindicated in patients with an estimated glomerular filtration rate (eGFR) below 30 mL/min/1.73 m 2 [see Contraindications (4) and Warnings and Precautions (5.1) ] . JANUMET is not recommended in patients with an eGFR between 30 and less than 45 mL/min/1.73 m 2 because these patients require a lower dosage of sitagliptin than what is available in the fixed combination JANUMET product. 2.3 Discontinuation for Iodinated Contrast Imaging Procedures Discontinue JANUMET at the time of, or prior to, an iodinated contrast imaging procedure in patients with an eGFR between 30 and 60 mL/min/1.73 m 2 ; in patients with a history of liver disease, alcoholism, or heart failure; or in patients who will be administered intra-arterial iodinated contrast. Re-evaluate eGFR 48 hours after the imaging procedure; restart JANUMET if renal function is stable [see Warnings and Precautions (5.1) ] .

JANUMET is contraindicated in patients with: Severe renal impairment (eGFR below 30 mL/min/1.73 m 2 ) [see Warnings and Precautions (5.1) ] . Acute or chronic metabolic acidosis, including diabetic ketoacidosis. History of a serious hypersensitivity reaction to JANUMET, sitagliptin, or metformin, such as anaphylaxis or angioedema. [See Warnings and Precautions (5.7) ; Adverse Reactions (6.2) .] Severe renal impairment: (eGFR below 30 mL/min/1.73 m 2 ) ( 4 ) Metabolic acidosis, including diabetic ketoacidosis. ( 4 ) History of a serious hypersensitivity reaction to JANUMET, sitagliptin, or metformin, such as anaphylaxis or angioedema. ( 5.7 , 6.2 )

The following adverse reactions are also discussed elsewhere in the labeling: Lactic Acidosis [see Warnings and Precautions (5.1) ] Pancreatitis [see Warnings and Precautions (5.2) ] Heart Failure [see Warnings and Precautions (5.3) ] Acute Renal Failure [see Warnings and Precautions (5.4) ] Vitamin B 12 Deficiency [see Warnings and Precautions (5.5) ] Hypoglycemia with Concomitant Use with Insulin or Insulin Secretagogues [see Warnings and Precautions (5.6) ] Hypersensitivity Reactions [see Warnings and Precautions (5.7) ] Severe and Disabling Arthralgia [see Warnings and Precautions (5.8) ] Bullous Pemphigoid [see Warnings and Precautions (5.9) ] The most common adverse reactions reported in ≥5% of patients simultaneously started on sitagliptin and metformin and more commonly than in patients treated with placebo were diarrhea, upper respiratory tract infection, and headache. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Merck Sharp & Dohme LLC at 1-877-888-4231 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. Sitagliptin and Metformin Coadministration in Patients with Type 2 Diabetes Inadequately Controlled on Diet and Exercise Table 1 summarizes the most common (≥5% of patients) adverse reactions reported (regardless of investigator assessment of causality) in a 24-week placebo-controlled factorial study in which sitagliptin and metformin were coadministered to patients with type 2 diabetes inadequately controlled on diet and exercise. Table 1: Sitagliptin and Metformin Coadministered to Patients with Type 2 Diabetes Inadequately Controlled on Diet and Exercise: Adverse Reactions Reported (Regardless of Investigator Assessment of Causality) in ≥5% of Patients Receiving Combination Therapy (and Greater than in Patients Receiving Placebo) Intent-to-treat population. Number of Patients (%) Placebo Sitagliptin 100 mg once daily Metformin HCl 500 mg/ Metformin HCl 1000 mg twice daily Data pooled for the patients given the lower and higher doses of metformin. Sitagliptin 50 mg twice daily + Metformin HCl 500 mg/ Metformin HCl 1000 mg twice daily N = 176 N = 179 N = 364 N = 372 Diarrhea 7 (4.0) 5 (2.8) 28 (7.7) 28 (7.5) Upper Respiratory Tract Infection 9 (5.1) 8 (4.5) 19 (5.2) 23 (6.2) Headache 5 (2.8) 2 (1.1) 14 (3.8) 22 (5.9) Sitagliptin Add-on Therapy in Patients with Type 2 Diabetes Inadequately Controlled on Metformin Alone In a 24-week placebo-controlled trial of sitagliptin 100 mg administered once daily added to a twice daily metformin regimen, there were no adverse reactions reported regardless of investigator assessment of causality in ≥5% of patients and more commonly than in patients given placebo. Discontinuation of therapy due to clinical adverse reactions was similar to the placebo treatment group (sitagliptin and metformin, 1.9%; placebo and metformin, 2.5%). Gastrointestinal Adverse Reactions The incidences of pre-selected gastrointestinal adverse experiences in patients treated with sitagliptin and metformin were similar to those reported for patients treated with metformin alone. See Table 2 . Table 2: Pre-selected Gastrointestinal Adverse Reactions (Regardless of Investigator Assessment of Causality) Reported in Patients with Type 2 Diabetes Receiving Sitagliptin and Metformin Number of Patients (%) Study of Sitagliptin and Metformin in Patients Inadequately Controlled on Diet and Exercise Study of Sitagliptin Add-on in Patients Inadequately Controlled on Metformin Alone Placebo Sitagliptin 100 mg once daily Metformin HCl 500 mg/ Metformin HCl 1000 mg twice daily Data pooled for the patients given the lower and higher doses of metformin. Sitagliptin 50 mg twice daily + Metformin HCl 500 mg/ Metformin HCl 1000 mg twice daily Placebo and Metformin HCl ≥1500 mg daily Sitagliptin 100 mg once daily and Metformin HCl ≥1500 mg daily N = 176 N = 179 N = 364 N = 372 N = 237 N = 464 Diarrhea 7 (4.0) 5 (2.8) 28 (7.7) 28 (7.5) 6 (2.5) 11 (2.4) Nausea 2 (1.1) 2 (1.1) 20 (5.5) 18 (4.8) 2 (0.8) 6 (1.3) Vomiting 1 (0.6) 0 (0.0) 2 (0.5) 8 (2.2) 2 (0.8) 5 (1.1) Abdominal Pain Abdominal discomfort was included in the analysis of abdominal pain in the study of initial therapy. 4 (2.3) 6 (3.4) 14 (3.8) 11 (3.0) 9 (3.8) 10 (2.2) Sitagliptin in Combination with Metformin and Glimepiride In a 24-week placebo-controlled study of sitagliptin 100 mg as add-on therapy in patients with type 2 diabetes inadequately controlled on metformin and glimepiride (sitagliptin, N=116; placebo, N=113), the adverse reactions reported regardless of investigator assessment of causality in ≥5% of patients treated with sitagliptin and more commonly than in patients treated with placebo were: hypoglycemia (Table 3) and headache (6.9%, 2.7%). Sitagliptin in Combination with Metformin and Rosiglitazone In a placebo-controlled study of sitagliptin 100 mg as add-on therapy in patients with type 2 diabetes inadequately controlled on metformin and rosiglitazone (sitagliptin, N=181; placebo, N=97), the adverse reactions reported regardless of investigator assessment of causality through Week 18 in ≥5% of patients treated with sitagliptin and more commonly than in patients treated with placebo were: upper respiratory tract infection (sitagliptin, 5.5%; placebo, 5.2%) and nasopharyngitis (6.1%, 4.1%). Through Week 54, the adverse reactions reported regardless of investigator assessment of causality in ≥5% of patients treated with sitagliptin and more commonly than in patients treated with placebo were: upper respiratory tract infection (sitagliptin, 15.5%; placebo, 6.2%), nasopharyngitis (11.0%, 9.3%), peripheral edema (8.3%, 5.2%), and headache (5.5%, 4.1%). Sitagliptin in Combination with Metformin and Insulin In a 24-week placebo-controlled study of sitagliptin 100 mg as add-on therapy in patients with type 2 diabetes inadequately controlled on metformin and insulin (sitagliptin, N=229; placebo, N=233), the only adverse reaction reported regardless of investigator assessment of causality in ≥5% of patients treated with sitagliptin and more commonly than in patients treated with placebo was hypoglycemia (Table 3). Hypoglycemia In the above studies (N=5), adverse reactions of hypoglycemia were based on all reports of symptomatic hypoglycemia; a concurrent glucose measurement was not required although most (77%) reports of hypoglycemia were accompanied by a blood glucose measurement ≤70 mg/dL. When the combination of sitagliptin and metformin was coadministered with a sulfonylurea or with insulin, the percentage of patients reporting at least one adverse reaction of hypoglycemia was higher than that observed with placebo and metformin coadministered with a sulfonylurea or with insulin (Table 3). Table 3: Incidence and Rate of Hypoglycemia Adverse reactions of hypoglycemia were based on all reports of symptomatic hypoglycemia; a concurrent glucose measurement was not required: Intent-to-treat population. (Regardless of Investigator Assessment of Causality) in Placebo-Controlled Clinical Studies of Sitagliptin in Combination with Metformin Coadministered with Glimepiride or Insulin Add-On to Glimepiride + Metformin (24 weeks) Sitagliptin 100 mg + Metformin + Glimepiride Placebo + Metformin + Glimepiride N = 116 N = 113 Overall (%) 19 (16.4) 1 (0.9) Rate (episodes/patient-year) Based on total number of events (i.e., a single patient may have had multiple events). 0.82 0.02 Severe (%) Severe events of hypoglycemia were defined as those events requiring medical assistance or exhibiting depressed level/loss of consciousness or seizure. 0 (0.0) 0 (0.0) Add-On to Insulin + Metformin (24 weeks) Sitagliptin 100 mg + Metformin + Insulin Placebo + Metformin + Insulin N = 229 N = 233 Overall (%) 35 (15.3) 19 (8.2) Rate (episodes/patient-year) 0.98 0.61 Severe (%) 1 (0.4) 1 (0.4) The overall incidence of reported adverse reactions of hypoglycemia in patients with type 2 diabetes inadequately controlled on diet and exercise was 0.6% in patients given placebo, 0.6% in patients given sitagliptin alone, 0.8% in patients given metformin alone, and 1.6% in patients given sitagliptin in combination with metformin. In patients with type 2 diabetes inadequately controlled on metformin alone, the overall incidence of adverse reactions of hypoglycemia was 1.3% in patients given add-on sitagliptin and 2.1% in patients given add-on placebo. In the study of sitagliptin and add-on combination therapy with metformin and rosiglitazone, the overall incidence of hypoglycemia was 2.2% in patients given add-on sitagliptin and 0.0% in patients given add-on placebo through Week 18. Through Week 54, the overall incidence of hypoglycemia was 3.9% in patients given add-on sitagliptin and 1.0% in patients given add-on placebo. In an additional, 30-week placebo-controlled, study of patients with type 2 diabetes inadequately controlled with metformin comparing the maintenance of sitagliptin 100 mg versus withdrawal of sitagliptin when initiating basal insulin therapy, the event rate and incidence of documented symptomatic hypoglycemia (blood glucose measurement ≤70 mg/dL) did not differ between the sitagliptin and placebo groups. Vital Signs and Electrocardiograms With the combination of sitagliptin and metformin, no clinically meaningful changes in vital signs or in ECG (including in QTc interval) were observed. Pancreatitis In a pooled analysis of 19 double-blind clinical trials that included data from 10,246 patients randomized to receive sitagliptin 100 mg/day (N=5429) or corresponding (active or placebo) control (N=4817), the incidence of acute pancreatitis was 0.1 per 100 patient-years in each group (4 patients with an event in 4708 patient-years for sitagliptin and 4 patients with an event in 3942 patient-years for control). Sitagliptin The most common adverse experience in sitagliptin monotherapy reported regardless of investigator assessment of causality in ≥5% of patients and more commonly than in patients given placebo was nasopharyngitis. Metformin The most common (>5%) established adverse reactions due to initiation of metformin therapy are diarrhea, nausea/vomiting, flatulence, abdominal discomfort, indigestion, asthenia, and headache. Laboratory Tests Sitagliptin The incidence of laboratory adverse reactions was similar in patients treated with sitagliptin and metformin (7.6%) compared to patients treated with placebo and metformin (8.7%). In most but not all studies, a small increase in white blood cell count (approximately 200 cells/microL difference in WBC vs placebo; mean baseline WBC approximately 6600 cells/microL) was observed due to a small increase in neutrophils. This change in laboratory parameters is not considered to be clinically relevant. Metformin In controlled clinical trials of metformin of 29 weeks duration, a decrease to subnormal levels of previously normal serum vitamin B 12 levels, without clinical manifestations, was observed in approximately 7% of patients. Such decrease, possibly due to interference with B 12 absorption from the B 12 -intrinsic factor complex, is, however, very rarely associated with anemia and appears to be rapidly reversible with discontinuation of metformin or vitamin B 12 supplementation. 6.2 Postmarketing Experience Additional adverse reactions have been identified during postapproval use of JANUMET, sitagliptin, or metformin. Because these reactions are reported voluntarily from a population of uncertain size, it is generally not possible to reliably estimate their frequency or establish a causal relationship to drug exposure. Hypersensitivity reactions including anaphylaxis, angioedema, rash, urticaria, cutaneous vasculitis, and exfoliative skin conditions including Stevens-Johnson syndrome ; upper respiratory tract infection; hepatic enzyme elevations; acute pancreatitis, including fatal and non-fatal hemorrhagic and necrotizing pancreatitis [see Indications and Usage (1) ]; worsening renal function, including acute renal failure (sometimes requiring dialysis) and tubulointerstitial nephritis; severe and disabling arthralgia; bullous pemphigoid; constipation; vomiting; headache; myalgia; pain in extremity; back pain; pruritus; mouth ulceration; stomatitis; cholestatic, hepatocellular, and mixed hepatocellular liver injury; rhabdomyolysis.

Table 4 presents clinically significant drug interactions with JANUMET: Table 4: Clinically Significant Drug Interactions with JANUMET Carbonic Anhydrase Inhibitors Clinical Impact: Carbonic anhydrase inhibitors frequently cause a decrease in serum bicarbonate and induce non-anion gap, hyperchloremic metabolic acidosis. Concomitant use of these drugs with JANUMET may increase the risk for lactic acidosis. Intervention: Consider more frequent monitoring of these patients. Examples: Topiramate, zonisamide, acetazolamide or dichlorphenamide. Drugs that Reduce Metformin Clearance Clinical Impact: Concomitant use of drugs that interfere with common renal tubular transport systems involved in the renal elimination of metformin (e.g., organic cationic transporter-2 [OCT 2 ] / multidrug and toxin extrusion [MATE] inhibitors) could increase systemic exposure to metformin and may increase the risk for lactic acidosis [see Clinical Pharmacology (12.3) ]. Intervention: Consider the benefits and risks of concomitant use with JANUMET. Examples: Ranolazine, vandetanib, dolutegravir, and cimetidine. Alcohol Clinical Impact: Alcohol is known to potentiate the effect of metformin on lactate metabolism. Intervention: Warn patients against alcohol intake while receiving JANUMET. Insulin Secretagogues or Insulin Clinical Impact: Coadministration of JANUMET with an insulin secretagogue (e.g., sulfonylurea) or insulin may increase the risk of hypoglycemia. Intervention: Patients receiving an insulin secretagogue or insulin may require lower doses of the insulin secretagogue or insulin. Drugs Affecting Glycemic Control Clinical Impact: Certain drugs tend to produce hyperglycemia and may lead to loss of glycemic control. Intervention: When such drugs are administered to a patient receiving JANUMET, observe the patient closely for loss of blood glucose control. When such drugs are withdrawn from a patient receiving JANUMET, observe the patient closely for hypoglycemia. Examples: Thiazides and other diuretics, corticosteroids, phenothiazines, thyroid products, estrogens, oral contraceptives, phenytoin, nicotinic acid, sympathomimetics, calcium channel blockers, and isoniazid. Carbonic anhydrase inhibitors may increase risk of lactic acidosis. Consider more frequent monitoring. ( 7 ) Drugs that reduce metformin clearance (such as ranolazine, vandetanib, dolutegravir, and cimetidine) may increase the accumulation of metformin. Consider the benefits and risks of concomitant use. ( 7 ) Alcohol can potentiate the effect of metformin on lactate metabolism. Warn patients against excessive alcohol intake. ( 7 )

Store at 20-25°C (68-77°F), excursions permitted to 15-30°C (59-86°F). [See USP Controlled Room Temperature.]