Exenatide

5 WARNINGS AND PRECAUTIONS Acute Pancreatitis : Has been observed in patients treated with GLP-1 receptor agonists, including exenatide. Discontinue if pancreatitis is suspected. ( 5.1 ) Never share an exenatide injection pen between patients, even if the needle is changed. ( 5.2 ) Hypoglycemia with Concomitant Use of Insulin Secretagogues or Insulin : Patients taking an insulin secretagogue or insulin may have an increased risk of hypoglycemia, including severe hypoglycemia. Reduction in the dose of insulin secretagogues or insulin may be necessary. ( 5.3 ) Acute Kidney Injury Due to Volume Depletion : Monitor renal function in patients reporting adverse reactions that could lead to volume depletion. ( 5.4 ) Severe Gastrointestinal Adverse Reactions : Use has been associated with gastrointestinal adverse reactions, sometimes severe. Exenatide is not recommended in patients with severe gastroparesis. ( 5.5 ) Immunogenicity : Patients may develop antibodies to exenatide. If there is worsening glycemic control or failure to achieve target glycemic control, consider alternative antidiabetic therapy. ( 5.6 ) Hypersensitivity : Serious hypersensitivity reactions (e.g., anaphylaxis and angioedema) have been reported. Discontinue exenatide and promptly seek medical advice. ( 5.7 ) Drug-induced Immune-mediated Thrombocytopenia : Serious bleeding which may be fatal has been reported. Discontinue exenatide promptly and avoid re-exposure to exenatide. ( 5.8 ) Acute Gallbladder Disease: If cholelithiasis or cholecystitis are suspected, gallbladder studies are indicated. ( 5.9 ) Pulmonary Aspiration During General Anesthesia or Deep Sedation: Has been reported in patients receiving GLP-1 receptor agonists undergoing elective surgeries or procedures. Instruct patients to inform healthcare providers of any planned surgeries or procedures. ( 5.10 )

5.1 Acute Pancreatitis Acute pancreatitis, including fatal and non-fatal hemorrhagic or necrotizing pancreatitis, has been observed in patients treated with glucagon-like peptide-1 (GLP-1) receptor agonists, including exenatide [see Adverse Reactions (6.2) ]. After initiation of exenatide, observe patients carefully for signs and symptoms of acute pancreatitis which may include persistent or severe abdominal pain (sometimes radiating to the back) and which may or may not be accompanied by nausea or vomiting. If pancreatitis is suspected, discontinue exenatide and initiate appropriate management.

5.2 Never Share an Exenatide Injection Pen Between Patients Exenatide injection pens must never be shared between patients, even if the needle is changed. Pen-sharing poses a risk for transmission of blood-borne pathogens.

5.3 Hypoglycemia with Concomitant Use of Insulin Secretagogues or Insulin Patients receiving exenatide in combination with an insulin secretagogue (e.g., sulfonylurea) or insulin may have an increased risk of hypoglycemia including severe hypoglycemia [see Adverse Reactions (6) and Drug Interactions (7) ] . The risk of hypoglycemia may be lowered by a reduction in the dose of sulfonylurea (or other concomitantly administered insulin secretagogue) or insulin. Inform patients using these concomitant medications of the risk of hypoglycemia and educate them on the signs and symptoms of hypoglycemia.

5.4 Acute Kidney Injury Due to Volume Depletion There have been post-marketing reports of acute kidney injury, in some cases requiring hemodialysis, in patients treated with GLP-1 receptor agonists, exenatide [see Adverse Reactions (6.2) ]. The majority of the reported events occurred in patients who experienced gastrointestinal reactions leading to dehydration such as nausea, vomiting, or diarrhea [see Adverse Reactions (6) ]. Monitor renal function in patients reporting adverse reactions to exenatide that could lead to volume depletion, especially during dosage initiation and escalation of exenatide. Exenatide is not recommended in patients with severe renal impairment (creatinine clearance <30 mL/min) or end-stage renal disease and should be used with caution in patients with renal transplantation [see Use in Specific Populations (8.6) ] .

5.5 Severe Gastrointestinal Adverse Reactions Use of GLP-1 receptor agonists, including exenatide, has been associated with gastrointestinal adverse reactions, sometimes severe [see Adverse Reactions (6) ]. Severe gastrointestinal adverse reactions have also been reported postmarketing with GLP-1 receptor agonists. Exenatide is not recommended in patients with severe gastroparesis.

5.6 Immunogenicity Patients may develop antibodies to exenatide following treatment with exenatide. Antibody levels were measured in 90% of subjects in the 30-week, 24-week, and 16-week placebo-controlled studies and the 30-week comparator-controlled study of exenatide. In 3%, 4%, 1% and 1% of these patients, respectively, antibody formation was associated with an attenuated glycemic response. If there is worsening glycemic control or failure to achieve targeted glycemic control, alternative antidiabetic therapy should be considered [see Adverse Reactions (6.1) ] .

5.7 Hypersensitivity There have been post-marketing reports of serious hypersensitivity reactions (e.g., anaphylaxis and angioedema) in patients treated with exenatide. If a hypersensitivity reaction occurs, the patient should discontinue exenatide and other suspect medications and promptly seek medical advice. Inform and closely monitor patients with a history of anaphylaxis or angioedema with another GLP-1 receptor agonist for allergic reactions, because it is unknown whether such patients will be predisposed to anaphylaxis with exenatide [see Adverse Reactions (6.2) ] .

5.8 Drug-Induced Thrombocytopenia Serious bleeding, which may be fatal, from drug-induced immune-mediated thrombocytopenia has been reported in the post-marketing setting with exenatide use. Drug-induced thrombocytopenia is an immune-mediated reaction, with exenatide-dependent anti-platelet antibodies. In the presence of exenatide, these antibodies cause platelet destruction. If drug-induced thrombocytopenia is suspected, discontinue exenatide immediately and do not re-expose the patient to exenatide [see Adverse Reactions (6.2) ] .

5.9 Acute Gallbladder Disease Acute events of gallbladder disease such as cholelithiasis or cholecystitis have been reported in GLP-1 receptor agonist trials and post-marketing. In a clinical study with exenatide, 1.9% of exenatide-treated patients and 1.4% of placebo-treated patients reported an acute event of gallbladder disease, such as cholelithiasis or cholecystitis. If cholelithiasis is suspected, gallbladder studies and appropriate clinical follow-up are indicated.

5.10 Pulmonary Aspiration During General Anesthesia or Deep Sedation Exenatide delays gastric emptying [see Clinical Pharmacology (12.2) ] . There have been rare post-marketing reports of pulmonary aspiration in patients receiving GLP-1 receptor agonists undergoing elective surgeries or procedures requiring general anesthesia or deep sedation who had residual gastric contents despite reported adherence to preoperative fasting recommendations. Available data are insufficient to inform recommendations to mitigate the risk of pulmonary aspiration during general anesthesia or deep sedation in patients taking exenatide, including whether modifying preoperative fasting recommendations or temporarily discontinuing exenatide could reduce the incidence of retained gastric contents. Instruct patients to inform healthcare providers prior to any planned surgeries or procedures if they are taking exenatide.

The following serious adverse reactions are described below or elsewhere in the prescribing information: Acute Pancreatitis [see Warnings and Precautions (5.1) ] Never Share an Exenatide Pen Between Patients [see Warnings and Precautions (5.2) ] Hypoglycemia with Concomitant Use of Insulin Secretagogues or Insulin [see Warnings and Precautions (5.3) ] Acute Kidney Injury Due to Volume Depletion [see Warnings and Precautions (5.4) ] Severe Gastrointestinal Adverse Reactions [see Warnings and Precautions (5.5) ] Immunogenicity [see Warnings and Precautions (5.6) ] Hypersensitivity [see Warnings and Precautions (5.7) ] Drug-Induced Thrombocytopenia [see Warnings and Precautions (5.8) ] Acute Gallbladder Disease [see Warnings and Precautions (5.9) ] Pulmonary Aspiration During General Anesthesia or Deep Sedation [see Warnings and Precautions (5.10) ] Most common (≥ 5%) and occurring more frequently than placebo in clinical trials: nausea, hypoglycemia, vomiting, diarrhea, feeling jittery, dizziness, headache, dyspepsia, constipation, asthenia. Nausea usually decreases over time. ( 5.3 , 6 ) To report SUSPECTED ADVERSE REACTIONS, contact Amneal Pharmaceuticals LLC at 1-877-835-5472 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

6.1 Clinical Trial 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. Hypoglycemia Table 1 summarizes the incidence and rate of hypoglycemia with exenatide in six placebo-controlled clinical trials. Table 1: Incidence (%) and Rate of Hypoglycemia when Exenatide was used as Monotherapy or with Concomitant Antidiabetic Therapy in Six Placebo-Controlled Clinical Trials * Placebo BID Exenatide 5 mcg BID Exenatide 10 mcg BID Monotherapy (24 Weeks) N 77 77 78 % Overall 1.3% 5.2% 3.8% Rate (episodes/patient-year) 0.03 0.21 0.52 % Severe 0.0% 0.0% 0.0% With Metformin (30 Weeks) N 113 110 113 % Overall 5.3% 4.5% 5.3% Rate (episodes/patient-year) 0.12 0.13 0.12 % Severe 0.0% 0.0% 0.0% With a Sulfonylurea (30 Weeks) N 123 125 129 % Overall 3.3% 14.4% 35.7% Rate (episodes/patient-year) 0.07 0.64 1.61 % Severe 0.0% 0.0% 0.0% With Metformin and a Sulfonylurea (30 Weeks) N 247 245 241 % Overall 12.6% 19.2% 27.8% Rate (episodes/patient-year) 0.58 0.78 1.71 % Severe 0.0% 0.4% 0.0% With a Thiazolidinedione (16 Weeks) N 112 not evaluated 121 % Overall 7.1% not evaluated 10.7% Rate (episodes/patient-years) 0.56 not evaluated 0.98 % Severe 0.0% not evaluated 0.0% With Insulin Glargine with or without Metformin and/or Thiazolidinedione (30 Weeks) † N 122 not evaluated 137 % Overall 29.5% not evaluated 24.8% Rate (episodes/patient-years) 1.58 not evaluated 1.61 % Severe 0.8% not evaluated 0.0% * A hypoglycemic episode was recorded if a patient reported symptoms of hypoglycemia with or without a blood glucose value consistent with hypoglycemia. Severe hypoglycemia was defined as an event with symptoms consistent with hypoglycemia requiring the assistance of another person and associated with either a documented blood glucose value < 54 mg/dL or prompt recovery after treatment for hypoglycemia. † When exenatide was initiated in combination with insulin glargine, the dose of insulin glargine was decreased by 20% in patients with an HbA 1c ≤ 8.0% to minimize the risk of hypoglycemia. See Table 10 for insulin dose titration algorithm. N = number of Intent-to-Treat subjects in each treatment group. Immunogenicity Antibodies were assessed in 90% of subjects in the 30-week, 24-week, and 16-week studies of exenatide. In the 30-week controlled trials of exenatide add-on to metformin and/or sulfonylurea, antibodies were assessed at 2- to 6-week intervals. The mean antibody titer peaked at Week 6 and was reduced by 55% by Week 30. Three hundred and sixty patients (38%) had low titer antibodies (< 625) to exenatide at 30 weeks. The level of glycemic control (HbA 1c ) in these patients was generally comparable to that observed in the 534 patients (56%) without antibody titers. An additional 59 patients (6%) had higher titer antibodies (≥ 625) at 30 weeks. Of these patients, 32 (3% overall) had an attenuated glycemic response to exenatide; the remaining 27 (3% overall) had a glycemic response comparable to that of patients without antibodies. In the 16-week trial of exenatide add-on to thiazolidinediones, with or without metformin, 36 patients (31%) had low titer antibodies to exenatide at 16 weeks. The level of glycemic control in these patients was generally comparable to that observed in the 69 patients (60%) without antibody titer. An additional 10 patients (9%) had higher titer antibodies at 16 weeks. Of these patients, 4 (4% overall) had an attenuated glycemic response to exenatide; the remaining 6 (5% overall) had a glycemic response comparable to that of patients without antibodies. In the 24-week trial of exenatide used as monotherapy, 40 patients (28%) had low titer antibodies to exenatide at 24 weeks. The level of glycemic control in these patients was generally comparable to that observed in the 101 patients (70%) without antibody titers. An additional 3 patients (2%) had higher titer antibodies at 24 weeks. Of these patients, 1 (1% overall) had an attenuated glycemic response to exenatide; the remaining 2 (1% overall) had a glycemic response comparable to that of patients without antibodies. Antibodies to exenatide were not assessed in the 30-week placebo-controlled trial of exenatide used in combination with insulin glargine. In the 30-week comparator-controlled trial of exenatide used in combination with insulin glargine and metformin, 60 patients (20%) had low titer antibodies to exenatide at 30 weeks. The level of glycemic control in these patients was generally comparable to that observed in the 234 patients (77%) without antibody titers. An additional 10 patients (3%) had higher titer antibodies at 30 weeks. Of these patients, 2 (1% overall) had an attenuated glycemic response to exenatide; the remaining 8 (3% overall) had a glycemic response comparable to that of patients without antibodies. Two hundred and ten patients with antibodies to exenatide in the exenatide clinical trials were tested for the presence of cross-reactive antibodies to GLP-1 and/or glucagon. No treatment-emergent cross-reactive antibodies were observed across the range of titers. Other Adverse Reactions Monotherapy For the 24-week placebo-controlled study of exenatide used as a monotherapy, Table 2 summarizes adverse reactions (excluding hypoglycemia) occurring with an incidence ≥ 2% and occurring more frequently in exenatide-treated patients compared with placebo-treated patients. Table 2: Treatment-Emergent Adverse Reactions ≥ 2% Incidence with Exenatide used as Monotherapy (excluding Hypoglycemia) * Monotherapy Placebo BID N=77 % All Exenatide BID N=155 % Nausea 0 8 Vomiting 0 4 Dyspepsia 0 3 * In a 24-week placebo-controlled trial. BID = twice daily. Adverse reactions reported in ≥ 1.0% to < 2.0% of patients receiving exenatide and reported more frequently than with placebo included decreased appetite, diarrhea and dizziness. The most frequently reported adverse reaction associated with exenatide, nausea, occurred in a dose-dependent fashion. Two of the 155 patients treated with exenatide withdrew due to adverse reactions of headache and nausea. No placebo-treated patients withdrew due to adverse reactions. Cholelithiasis and cholecystitis In a clinical study with exenatide, 1.9% of exenatide-treated patients and 1.4% of placebo-treated patients reported an acute event of gallbladder disease, such as cholelithiasis or cholecystitis. Combination Therapy Add-On to Metformin and/or Sulfonylurea In the three 30-week controlled trials of exenatide add-on to metformin and/or sulfonylurea, adverse reactions (excluding hypoglycemia) with an incidence ≥ 2% and occurring more frequently in exenatide-treated patients compared with placebo-treated patients are summarized in Table 3. Table 3: Treatment-Emergent Adverse Reactions ≥ 2% Incidence and Greater Incidence with Exenatide Treatment used with Metformin and/or a Sulfonylurea (excluding Hypoglycemia) * Placebo BID N=483 % All Exenatide BID N=963 % Nausea 18 44 Vomiting 4 13 Diarrhea 6 13 Feeling Jittery 4 9 Dizziness 6 9 Headache 6 9 Dyspepsia 3 6 Asthenia 2 4 Gastroesophageal Reflux Disease 1 3 Hyperhidrosis 1 3 * In three 30-week placebo-controlled clinical trials. BID = twice daily. Adverse reactions reported in ≥ 1.0% to < 2.0% of patients receiving exenatide and reported more frequently than with placebo included decreased appetite. Nausea was the most frequently reported adverse reaction and occurred in a dose-dependent fashion. With continued therapy, the frequency and severity decreased over time in most of the patients who initially experienced nausea. Patients in the long-term uncontrolled open-label extension studies at 52 weeks reported no new types of adverse reactions than those observed in the 30-week controlled trials. The most common adverse reactions leading to withdrawal for exenatide-treated patients were nausea (3% of patients) and vomiting (1%). For placebo-treated patients, < 1% withdrew due to nausea and none due to vomiting. Add-On to Thiazolidinedione with or without Metformin For the 16-week placebo-controlled study of exenatide add-on to a thiazolidinedione, with or without metformin, Table 4 summarizes the adverse reactions (excluding hypoglycemia) with an incidence of ≥ 2% and occurring more frequently in exenatide-treated patients compared with placebo-treated patients. Table 4: Treatment-Emergent Adverse Reactions ≥ 2% Incidence with Exenatide used with a Thiazolidinedione (TZD), with or without Metformin (MET) (excluding Hypoglycemia) * With a TZD or TZD/MET Placebo N=112 % All Exenatide BID N=121 % Nausea 15 40 Vomiting 1 13 Dyspepsia 1 7 Diarrhea 3 6 Gastroesophageal Reflux Disease 0 3 * In a 16-week placebo-controlled clinical trial. BID = twice daily. Adverse reactions reported in ≥ 1.0% to < 2.0% of patients receiving exenatide and reported more frequently than with placebo included decreased appetite. Chills (n=4) and injection-site reactions (n=2) occurred only in exenatide-treated patients. The two patients who reported an injection-site reaction had high titers of antibodies to exenatide. Two serious adverse events (chest pain and chronic hypersensitivity pneumonitis) were reported in the exenatide arm. No serious adverse events were reported in the placebo arm. The most common adverse reactions leading to withdrawal for exenatide-treated patients were nausea (9%) and vomiting (5%). For placebo-treated patients, < 1% withdrew due to nausea. Add-On to Insulin Glargine with or without Metformin and/or Thiazolidinedione (Placebo-Controlled) For the 30-week placebo-controlled study of exenatide as add-on to insulin glargine with or without oral antihyperglycemic medications, Table 5 summarizes adverse reactions (excluding hypoglycemia) occurring with an incidence ≥ 2% and occurring more frequently in exenatide-treated patients compared with placebo-treated patients. Table 5: Treatment-Emergent Adverse Reactions ≥ 2% Incidence with Exenatide used with Insulin Glargine with or without Oral Antihyperglycemic Medications (excluding Hypoglycemia) * With Insulin Glargine Placebo N=122 % All Exenatide BID N=137 % Nausea 8 41 Vomiting 4 18 Diarrhea 8 18 Headache 4 14 Constipation 2 10 Dyspepsia 2 7 Asthenia 1 5 Abdominal Distension 1 4 Decreased Appetite 0 3 Flatulence 1 2 Gastroesophageal Reflux Disease 1 2 * In a 30-week placebo-controlled clinical trial. BID = twice daily. The most frequently reported adverse reactions leading to withdrawal for exenatide-treated patients were nausea (5.1%) and vomiting (2.9%). No placebo-treated patients withdrew due to nausea or vomiting.

6.2 Post-marketing Experience The following additional adverse reactions have been reported during post-approval use of exenatide or other formulations of exenatide. Because these events 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. Blood : Drug-induced thrombocytopenia. Drug Interactions: International normalized ratio (INR) increased with concomitant warfarin use sometimes associated with bleeding [see Drug Interactions (7) ] . Gastrointestinal: Nausea, vomiting and/or diarrhea resulting in dehydration; abdominal distension, abdominal pain, eructation, constipation, flatulence, ileus, acute pancreatitis, hemorrhagic and necrotizing pancreatitis sometimes resulting in death, intestinal obstruction, severe constipation including fecal impaction. Hepatobiliary: Cholecystitis, cholelithiasis requiring cholecystectomy. Hypersensitivity: Injection-site reactions, generalized pruritus and/or urticaria, macular or papular rash, angioedema, anaphylactic reaction. Neurologic: Dysgeusia; somnolence, dysesthesia. Pulmonary: Pulmonary aspiration has occurred in patients receiving GLP-1 receptor agonists undergoing elective surgeries or procedures requiring general anesthesia or deep sedation. Renal: Altered renal function, including increased serum creatinine, renal impairment, worsened chronic renal failure or acute renal failure (sometimes requiring hemodialysis), kidney transplant and kidney transplant dysfunction. Skin and Subcutaneous Tissue: Alopecia.

Pregnancy: Use during pregnancy only if the potential benefit justifies the risk to the fetus. ( 8.1 )

8.1 Pregnancy Risk Summary Limited data with exenatide in pregnant women are not sufficient to determine a drug-associated risk for major birth defects or miscarriage. There are risks to the mother and fetus associated with poorly controlled diabetes in pregnancy (see Clinical Considerations) . Based on animal reproduction studies, there may be risks to the fetus from exposure to exenatide during pregnancy. Exenatide should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. Animal reproduction studies identified increased adverse fetal and neonatal outcomes from exposure to exenatide during pregnancy and lactation in association with maternal effects. In mice, exenatide administered during gestation and lactation caused increased neonatal deaths at systemic exposure 3-times the human exposure resulting from the maximum recommended human dose (MRHD) of 20 mcg/day for exenatide (see Data) . The estimated background risk of major birth defects is 6% to 10% in women with pre-gestational diabetes with an HbA 1c > 7 and has been reported to be as high as 20% to 25% in women with HbA 1c > 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 embryofetal risk Poorly controlled diabetes in pregnancy increases the maternal risk for diabetic ketoacidosis, preeclampsia, 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 studies evaluating reproduction and development in pregnant mice and rabbits, maternal animals were administered exenatide, the active ingredient in exenatide injection, by subcutaneous injection twice a day. In pregnant mice given 6, 68, 460, or 760 mcg/kg/day exenatide during fetal organogenesis, skeletal variations associated with slowed fetal growth, including changes in number of rib pairs or vertebral ossifications sites, and wavy ribs were observed at 760 mcg/kg/day, a dose that produced maternal toxicity and yielded systemic exposure 390-times the human exposure resulting from the MRHD of exenatide based on AUC comparison. In pregnant rabbits given 0.2, 2, 22, 156, or 260 mcg/kg/day exenatide during fetal organogenesis, irregular fetal skeletal ossifications were observed at 2 mcg/kg/day, a dose yielding systemic exposure up to 12-times the human exposure from the MRHD of exenatide based on AUC comparison. In maternal mice given 6, 68, or 760 mcg/kg/day exenatide from gestation day 6 through lactation day 20 (weaning), an increased number of neonatal deaths was observed on postpartum days 2 to 4 in dams given 6 mcg/kg/day, a dose yielding a systemic exposure 3-times the human exposure from the MRHD of exenatide based on AUC comparison.

8.2 Lactation Risk Summary There is no information regarding the presence of exenatide, in human milk, the effects of exenatide on the breastfed infant, or the effects of exenatide on milk production. Exenatide was present in the milk of lactating mice. However, due to species-specific differences in lactation physiology, the clinical relevance of these data is not clear (see Data) . The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for exenatide and any potential adverse effects on the breastfed child from exenatide or from the underlying maternal condition. Data In lactating mice subcutaneously injected twice a day with exenatide, the concentration of exenatide in milk was up to 2.5% of the concentration in maternal plasma.

8.4 Pediatric Use The safety and effectiveness of exenatide have not been established in pediatric patients. Effectiveness of exenatide was not demonstrated in a randomized, double-blind, placebo-controlled study conducted in 120 pediatric patients (78 received exenatide and 42 received placebo) aged 10 to 17 years with type 2 diabetes mellitus.

8.5 Geriatric Use Population pharmacokinetic analysis of patients ranging from 22 to 73 years of age suggests that age does not influence the pharmacokinetic properties of exenatide [see Clinical Pharmacology (12.3) ] . Exenatide was studied in 282 patients 65 years of age or older and in 16 patients 75 years of age or older. No differences in safety or effectiveness were observed between these patients and younger patients. Because elderly patients are more likely to have decreased renal function, care should be taken in dose selection in the elderly based on renal function.

8.6 Renal Impairment Exenatide is not recommended for use in patients with end-stage renal disease or severe renal impairment (creatinine clearance < 30 mL/min) and should be used with caution in patients with renal transplantation. In patients with end-stage renal disease receiving dialysis, single doses of exenatide 5 mcg were not well-tolerated due to gastrointestinal adverse reactions [see Clinical Pharmacology (12.3) ] .

8.7 Hepatic Impairment No pharmacokinetic study has been performed in patients with a diagnosis of acute or chronic hepatic impairment. Because exenatide is cleared primarily by the kidney, hepatic dysfunction is not expected to affect blood concentrations of exenatide [see Clinical Pharmacology (12.3) ] .

12.1 Mechanism of Action Incretins, such as glucagon-like peptide-1 (GLP-1), enhance glucose-dependent insulin secretion and exhibit other antihyperglycemic actions following their release into the circulation from the gut. Exenatide is a GLP-1 receptor agonist that enhances glucose-dependent insulin secretion by the pancreatic beta-cell, suppresses inappropriately elevated glucagon secretion, and slows gastric emptying. The amino acid sequence of exenatide partially overlaps that of human GLP-1. Exenatide has been shown to bind and activate the human GLP-1 receptor in vitro . This leads to an increase in both glucose-dependent synthesis of insulin, and in vivo secretion of insulin from pancreatic beta cells, by mechanisms involving cyclic AMP and/or other intracellular signaling pathways. Exenatide improves glycemic control by reducing fasting and postprandial glucose concentrations in patients with type 2 diabetes through the actions described below.

12.2 Pharmacodynamics Glucose-Dependent Insulin Secretion Exenatide has acute effects on pancreatic beta-cell responsiveness to glucose leading to insulin release predominantly in the presence of elevated glucose concentrations. This insulin secretion subsides as blood glucose concentrations decrease and approach euglycemia. However, exenatide does not impair the normal glucagon response to hypoglycemia. First-Phase Insulin Response In healthy individuals, robust insulin secretion occurs during the first 10 minutes following intravenous (IV) glucose administration. This secretion, known as the “first-phase insulin response,” is characteristically absent in patients with type 2 diabetes. The loss of the first-phase insulin response is an early beta-cell defect in type 2 diabetes. Administration of exenatide at therapeutic plasma concentrations restored first-phase insulin response to an IV bolus of glucose in patients with type 2 diabetes (Figure 1). Both first-phase insulin secretion and second-phase insulin secretion were significantly increased in patients with type 2 diabetes treated with exenatide compared with saline (p < 0.001 for both). Figure 1: Mean (+SEM) Insulin Secretion Rate during Infusion of Exenatide or Saline in Patients with Type 2 Diabetes and during Infusion of Saline in Healthy Subjects Glucagon Secretion In patients with type 2 diabetes, exenatide moderates glucagon secretion and lowers serum glucagon concentrations during periods of hyperglycemia. Lower glucagon concentrations lead to decreased hepatic glucose output and decreased insulin demand. Gastric Emptying Exenatide slows gastric emptying, thereby reducing the rate at which meal-derived glucose appears in the circulation. Food Intake In both animals and humans, administration of exenatide has been shown to reduce food intake. Postprandial Glucose In patients with type 2 diabetes, exenatide reduces postprandial plasma glucose concentrations (Figure 2). Figure 2: Mean (+SEM) Postprandial Plasma Glucose Concentrations on Day 1 of Exenatide a Treatment in Patients with Type 2 Diabetes Treated with Metformin, a Sulfonylurea, or Both (N = 54) Fasting Glucose In a single-dose crossover study in patients with type 2 diabetes and fasting hyperglycemia, immediate insulin release followed injection of exenatide. Plasma glucose concentrations were significantly reduced with exenatide compared with placebo (Figure 3). Figure 3: Mean (+SEM) Serum Insulin and Plasma Glucose Concentrations Following a One-Time Injection of Exenatide a or Placebo in Fasting Patients with Type 2 Diabetes (N = 12) Cardiac Electrophysiology The effect of exenatide 10 mcg subcutaneously on QTc interval was evaluated in a randomized, placebo-, and active-controlled (moxifloxacin 400 mg) crossover thorough QTc study in 62 healthy subjects. In this study with demonstrated ability to detect small effects, the upper bound of the 90% confidence interval for the largest placebo-adjusted, baseline-corrected QTc was below 10 msec. Thus, exenatide (10 mcg single-dose) was not associated with clinically meaningful prolongation of the QTc interval. 10 10 10 12.3 Pharmacokinetics Absorption Following SC administration to patients with type 2 diabetes, exenatide reaches median peak plasma concentrations in 2.1 hours. The mean peak exenatide concentration (C max ) was 211 pg/mL and overall mean area under the time-concentration curve (AUC 0-inf ) was 1,036 pg

• h/mL following SC administration of a 10-mcg dose of exenatide. Exenatide exposure (AUC) increased proportionally over the therapeutic dose range of 5 mcg to 10 mcg. The C max values increased less than proportionally over the same range. Similar exposure is achieved with SC administration of exenatide in the abdomen, thigh, or upper arm. Distribution The mean apparent volume of distribution of exenatide following SC administration of a single-dose of exenatide is 28.3 L. Metabolism and Elimination Nonclinical studies have shown that exenatide is predominantly eliminated by glomerular filtration with subsequent proteolytic degradation. The mean apparent clearance of exenatide in humans is 9.1 L/hour and the mean terminal half-life is 2.4 hours. These pharmacokinetic characteristics of exenatide are independent of the dose. In most individuals, exenatide concentrations are measurable for approximately 10 hours post-dose. Drug Interactions Acetaminophen When 1,000 mg acetaminophen elixir was given with 10 mcg exenatide (0 hour) and 1 hour, 2 hours and 4 hours after exenatide injection, acetaminophen AUCs were decreased by 21%, 23%, 24% and 14%, respectively; C max was decreased by 37%, 56%, 54% and 41%, respectively; T max was increased from 0.6 hour in the control period to 0.9 hour, 4.2 hours, 3.3 hours and 1.6 hours, respectively. Acetaminophen AUC, C max and T max were not significantly changed when acetaminophen was given 1 hour before exenatide injection. Digoxin Administration of repeated doses of exenatide (10 mcg BID) 30 minutes before oral digoxin (0.25 mg once daily) decreased the C max of digoxin by 17% and delayed the T max of digoxin by approximately 2.5 hours; however, the overall steady-state pharmacokinetic exposure (e.g., AUC) of digoxin was not changed. Lovastatin Administration of exenatide (10 mcg BID) 30 minutes before a single oral dose of lovastatin (40 mg) decreased the AUC and C max of lovastatin by approximately 40% and 28%, respectively, and delayed the T max by about 4 hours compared with lovastatin administered alone. In the 30-week controlled clinical trials of exenatide, the use of exenatide in patients already receiving HMG CoA reductase inhibitors was not associated with consistent changes in lipid profiles compared to baseline. Lisinopril In patients with mild to moderate hypertension stabilized on lisinopril (5 mg/day to 20 mg/day), exenatide (10 mcg BID) did not alter steady-state C max or AUC of lisinopril. Lisinopril steady-state T max was delayed by 2 hours. There were no changes in 24-hour mean systolic and diastolic blood pressure. Oral Contraceptives The effect of exenatide (10 mcg BID) on single and on multiple-doses of a combination oral contraceptive (30 mcg ethinyl estradiol plus 150 mcg levonorgestrel) was studied in healthy female subjects. Repeated daily doses of the oral contraceptive (OC) given 30 minutes after exenatide administration decreased the C max of ethinyl estradiol and levonorgestrel by 45% and 27%, respectively and delayed the T max of ethinyl estradiol and levonorgestrel by 3.0 hours and 3.5 hours, respectively, as compared to the oral contraceptive administered alone. Administration of repeated daily doses of the OC one hour prior to exenatide administration decreased the mean C max of ethinyl estradiol by 15% but the mean C max of levonorgestrel was not significantly changed as compared to when the OC was given alone. Exenatide did not alter the mean trough concentrations of levonorgestrel after repeated daily dosing of the oral contraceptive for both regimens. However, the mean trough concentration of ethinyl estradiol was increased by 20% when the OC was administered 30 minutes after exenatide administration injection as compared to when the OC was given alone. The effect of exenatide on OC pharmacokinetics is confounded by the possible food effect on OC in this study. Therefore, OC products should be administered at least one hour prior to exenatide injection. Warfarin Administration of warfarin (25 mg) 35 minutes after repeated doses of exenatide (5 mcg BID on Days 1 to 2 and 10 mcg BID on Days 3 to 9) in healthy volunteers delayed warfarin T max by approximately 2 hours. No clinically relevant effects on C max or AUC of S - and R -enantiomers of warfarin were observed. Exenatide did not significantly alter the pharmacodynamic properties (e.g., international normalized ratio) of warfarin [see Drug Interactions (7) ] . Specific Populations Patients with Renal Impairment Pharmacokinetics of exenatide was studied in subjects with normal, mild, or moderate renal impairment and subjects with end-stage renal disease. In subjects with mild to moderate renal impairment (creatinine clearance 30 mL/min to 80 mL/min), exenatide exposure was similar to that of subjects with normal renal function. However, in subjects with end-stage renal disease receiving dialysis, mean exenatide exposure increased by 3.37-fold compared to that of subjects with normal renal function [see Use in Specific Populations (8.6) ] . Patients with Hepatic Impairment No pharmacokinetic study has been performed in patients with a diagnosis of acute or chronic hepatic impairment [see Use in Specific Populations (8.7) ] . Age Population pharmacokinetic analysis of patients ranging from 22 to 73 years of age suggests that age does not influence the pharmacokinetic properties of exenatide [see Use in Specific Population (8.5) ] . Male and Female Patients Population pharmacokinetic analysis of male and female patients suggests that gender does not influence the distribution and elimination of exenatide. Racial or Ethnic Groups Population pharmacokinetic analysis of samples from White, Hispanic or Latino ethnicity, Asian and Black or African American patients suggests that race has no significant influence on the pharmacokinetics of exenatide. Body Mass Index Population pharmacokinetic analysis of patients with body mass indices (BMI) ≥ 30 kg/m 2 and < 30 kg/m 2 suggests that BMI has no significant effect on the pharmacokinetics of exenatide.

Absorption Following SC administration to patients with type 2 diabetes, exenatide reaches median peak plasma concentrations in 2.1 hours. The mean peak exenatide concentration (C max ) was 211 pg/mL and overall mean area under the time-concentration curve (AUC 0-inf ) was 1,036 pg

• h/mL following SC administration of a 10-mcg dose of exenatide. Exenatide exposure (AUC) increased proportionally over the therapeutic dose range of 5 mcg to 10 mcg. The C max values increased less than proportionally over the same range. Similar exposure is achieved with SC administration of exenatide in the abdomen, thigh, or upper arm. Distribution The mean apparent volume of distribution of exenatide following SC administration of a single-dose of exenatide is 28.3 L. Metabolism and Elimination Nonclinical studies have shown that exenatide is predominantly eliminated by glomerular filtration with subsequent proteolytic degradation. The mean apparent clearance of exenatide in humans is 9.1 L/hour and the mean terminal half-life is 2.4 hours. These pharmacokinetic characteristics of exenatide are independent of the dose. In most individuals, exenatide concentrations are measurable for approximately 10 hours post-dose. Drug Interactions Acetaminophen When 1,000 mg acetaminophen elixir was given with 10 mcg exenatide (0 hour) and 1 hour, 2 hours and 4 hours after exenatide injection, acetaminophen AUCs were decreased by 21%, 23%, 24% and 14%, respectively; C max was decreased by 37%, 56%, 54% and 41%, respectively; T max was increased from 0.6 hour in the control period to 0.9 hour, 4.2 hours, 3.3 hours and 1.6 hours, respectively. Acetaminophen AUC, C max and T max were not significantly changed when acetaminophen was given 1 hour before exenatide injection. Digoxin Administration of repeated doses of exenatide (10 mcg BID) 30 minutes before oral digoxin (0.25 mg once daily) decreased the C max of digoxin by 17% and delayed the T max of digoxin by approximately 2.5 hours; however, the overall steady-state pharmacokinetic exposure (e.g., AUC) of digoxin was not changed. Lovastatin Administration of exenatide (10 mcg BID) 30 minutes before a single oral dose of lovastatin (40 mg) decreased the AUC and C max of lovastatin by approximately 40% and 28%, respectively, and delayed the T max by about 4 hours compared with lovastatin administered alone. In the 30-week controlled clinical trials of exenatide, the use of exenatide in patients already receiving HMG CoA reductase inhibitors was not associated with consistent changes in lipid profiles compared to baseline. Lisinopril In patients with mild to moderate hypertension stabilized on lisinopril (5 mg/day to 20 mg/day), exenatide (10 mcg BID) did not alter steady-state C max or AUC of lisinopril. Lisinopril steady-state T max was delayed by 2 hours. There were no changes in 24-hour mean systolic and diastolic blood pressure. Oral Contraceptives The effect of exenatide (10 mcg BID) on single and on multiple-doses of a combination oral contraceptive (30 mcg ethinyl estradiol plus 150 mcg levonorgestrel) was studied in healthy female subjects. Repeated daily doses of the oral contraceptive (OC) given 30 minutes after exenatide administration decreased the C max of ethinyl estradiol and levonorgestrel by 45% and 27%, respectively and delayed the T max of ethinyl estradiol and levonorgestrel by 3.0 hours and 3.5 hours, respectively, as compared to the oral contraceptive administered alone. Administration of repeated daily doses of the OC one hour prior to exenatide administration decreased the mean C max of ethinyl estradiol by 15% but the mean C max of levonorgestrel was not significantly changed as compared to when the OC was given alone. Exenatide did not alter the mean trough concentrations of levonorgestrel after repeated daily dosing of the oral contraceptive for both regimens. However, the mean trough concentration of ethinyl estradiol was increased by 20% when the OC was administered 30 minutes after exenatide administration injection as compared to when the OC was given alone. The effect of exenatide on OC pharmacokinetics is confounded by the possible food effect on OC in this study. Therefore, OC products should be administered at least one hour prior to exenatide injection. Warfarin Administration of warfarin (25 mg) 35 minutes after repeated doses of exenatide (5 mcg BID on Days 1 to 2 and 10 mcg BID on Days 3 to 9) in healthy volunteers delayed warfarin T max by approximately 2 hours. No clinically relevant effects on C max or AUC of S - and R -enantiomers of warfarin were observed. Exenatide did not significantly alter the pharmacodynamic properties (e.g., international normalized ratio) of warfarin [see Drug Interactions (7) ] . Specific Populations Patients with Renal Impairment Pharmacokinetics of exenatide was studied in subjects with normal, mild, or moderate renal impairment and subjects with end-stage renal disease. In subjects with mild to moderate renal impairment (creatinine clearance 30 mL/min to 80 mL/min), exenatide exposure was similar to that of subjects with normal renal function. However, in subjects with end-stage renal disease receiving dialysis, mean exenatide exposure increased by 3.37-fold compared to that of subjects with normal renal function [see Use in Specific Populations (8.6) ] . Patients with Hepatic Impairment No pharmacokinetic study has been performed in patients with a diagnosis of acute or chronic hepatic impairment [see Use in Specific Populations (8.7) ] . Age Population pharmacokinetic analysis of patients ranging from 22 to 73 years of age suggests that age does not influence the pharmacokinetic properties of exenatide [see Use in Specific Population (8.5) ] . Male and Female Patients Population pharmacokinetic analysis of male and female patients suggests that gender does not influence the distribution and elimination of exenatide. Racial or Ethnic Groups Population pharmacokinetic analysis of samples from White, Hispanic or Latino ethnicity, Asian and Black or African American patients suggests that race has no significant influence on the pharmacokinetics of exenatide. Body Mass Index Population pharmacokinetic analysis of patients with body mass indices (BMI) ≥ 30 kg/m 2 and < 30 kg/m 2 suggests that BMI has no significant effect on the pharmacokinetics of exenatide.