Oral Antidiabetic Agents Dr Nihal Thomas MD DNB (Endo) MNAMS FRACP (Endo) FRCP(Edin) Professor and Head Unit-1, Department of Endocrinology, Diabetes and Metabolism Christian Medical college, Vellore, India

Development and Progression of Type 2 Diabetes* Progression of Disease Insulin resistance 100 Hepatic glucose production Relative % 50 Insulin level β-cell function Development and Progression of Type 2 Diabetes This conceptual diagram shows a proposed paradigm on the development and progression of pathophysiology in type 2 diabetes. The horizontal axis in the figure shows the years prior to and after diagnosis of diabetes. Insulin resistance rises during disease development and continues to rise during impaired glucose tolerance (IGT). Over time, insulin resistance remains stable during the progression of type 2 diabetes.1 The insulin secretion rate increases, to compensate for the decrease in insulin effectiveness due to insulin resistance. This increase is often misperceived as an increase in β-cell function. Thus, β-cell function can decrease even as insulin secretion increases. Over time, β-cell compensatory function deteriorates and insulin secretion decreases. β-cell function progressively fails.1 Initially, fasting glucose is maintained in near-normal ranges. The pancreatic β cells compensate by increasing insulin levels, leading to hyperinsulinemia. This compensation keeps glucose levels normalized for a time, but as β cells begin to fail, IGT develops with mild postprandial hyperglycemia. As the disease progresses, the β cells continue to fail, resulting in higher postprandial glucose (PPG) levels. With further loss of insulin secretory capacity, fasting glucose and hepatic glucose production increase.1 Once β cells cannot secrete sufficient insulin to maintain normal glycemia at the fasting or postprandial stage, type 2 diabetes (hyperglycemia) becomes evident. Insulin resistance and β-cell dysfunction are established well before type 2 diabetes is diagnosed.2 4–7 years Postprandial glucose Purpose: To address the common misconception that an increase in insulin secretion (hyperinsulinemia) connotes an improvement in β-cell function. Take-away: Both insulin resistance and β-cell dysfunction start early–and well before diabetes is diagnosed–leading to rises in fasting and PPG levels. Fasting glucose Impaired Glucose Tolerance Frank Diabetes Diabetes Diagnosis *Conceptual representation. Adapted with permission from Ramlo-Halsted et al. Prim Care. 1999;26:771–789. 6 References 1. Ramlo-Halsted BA, Edelman SV. The natural history of type 2 diabetes. Implications for clinical practice. Prim Care. 1999;26:771–789. 2. Kahn SE. The relative contributions of insulin resistance and beta-cell dysfunction to the pathophysiology of type 2 diabetes. Diabetologia. 2003;46:3–19.

ADA guidelines, 2008 recommend…

Meglitinide Analogs Sulphonylureas Alpha Glucosidase Inhibitors Metformin (Biguanides) Thiazolindinediones

Spectrum of Oral Hypoglycaemic Agents Metformin (Biguanides) Glybenclemide, Glicliazide Glipizide, Glimepiride Acarbose , Miglitol, Voglibose Repaglinide, Nateglinide Rosiglitazone , Pioglitazone Sitagliptin, Vildagliptin, Saxagliptin Biguanides Sulphonylureas -Glucosidase inhibitors Meglitinide analogues Thiazolidinediones DPPV-4 Inhibitors

What is the role of an ideal oral hypoglycaemic agent? Conserve islet cell function - delay the subsequent use of insulin. Improve patient compliance- single daily dosing. Reduce the incidence of hypoglycaemic events

Biguanides Act by inhibiting liver gluconeogenesis & increasing insulin sensitivity in other tissues Metformin is not metabolized, but excreted intact in 2-5 h

Metformin By ADA and EASD guidelines The primary drug of choice for diabetes

Metformin Indicated in most Type 2 DM Contraindicated in: a) Malabsorption or GI disturbances b) Low BMI---?less than 21kg/m2…….marked weight loss c) Organ Failure: Creatinine: >1.4mg/dl Liver failure: Acute/Chronic Cardiac Failure Hypotension/Sepsis Active Vitamin B12 Deficiency GI intolerance Relative Contraindication: Age

Initiate: - after meals - 250 to 500mg twice or thrice a day - Increase gradually if required in 1 or 2 weeks - mild loose stools in 10% initially, which reduces gradually -persistent loose stools in 5% -Sustained released forms: more effective- vehicle excreted in stool

Metformin: Dosing from 500mg twice daily to 1 gramme thrice a day Advantages: Perpetuates weight loss Can be combined with insulin to reduce insulin requirements Disadvantages: Nausea, Vomiting and diarhorrea(5%) Vitamin B12 Deficiency (0.5%)

Repaglinide/ Nateglinide Nonsulphonylurea insulin secretagogues Mechanism: Closes ATP-sensitive potassium channels on ß-cells. Binds to a site distinctly separate from the sulphonylureas.

Meglitinide Analogs Bind to ß cells via SU receptor Rapid absorption, metabolism & clearance, T1/2 < 1 h After www.bentham.org/sample-issues/cmc9-1/kecskemeti/fig8.gif

Nateglinide/Repaglinide K+ 140 kDa 65 KATP channel Sulphonylurea Receptor Quicker attachment Earlier Detachment

Insulin Levels in Nateglinide/Repaglinide Traditional Sulphonylurea

Advantages of Nateglinide/Repaglinide Flexibility in mealtime dosing- ‘Ramzan Drug’ No significant increase in bodyweight Can be utillised in mild to moderate renal failure Nateglinide: approved in hepatic failure Dosage: Repaglinide: 0.5mg/1mg/2mg/4mg per dose per meal Nateglinide: 60mg/120mg per dose per meal Lower incidence of hypoglycemia

Useful Situations elderly patients in whom hypoglycaemia is a concern patients with kidney failure or mild hepatic impairment patients taking low-dose sulphonylureas who encounter problems with hypoglycaemia Patients with irregular meal patterns Int J Clin Pract. 2003 Jul-Aug;57(6):535-41.

Disadvantages of Metaglinide derivatives Works predominantly in mild hyperglycaemia Less convincing with fasting hyperglycaemia First line drug with little adjuvant potential

Mostly long metabolic T1/2 Stimulate insulin release from ß cells via binding to the SU receptor = K+ATP channel Mostly long metabolic T1/2 Sulfonylureas After www.bentham.org/sample-issues/cmc9-1/kecskemeti/fig-1.gif

Glimepiride

Modes of action: Glimepiride K+ 140 kDa 65  - cell membrane KATP channel Most Sulphonylureas Glimepiride Glimepiride Sulphonylurea Receptor GLUT-4 So What ?? 65kDa Component absent in Cardiovascular System Safer to use in patients with a higher cardiovascular risk

Type II Diabetes and Exercise Improvement in insulin Sensitivity: Activates intracellular GLUT-4 glucose transporters (Effect lost in 48 hours) Conventional Sulphonylureas: failure of insulin suppression Hypoglycaemia / overeating in the morning/ weight gain.

Insulin Suppression During Exercise BETTER INSULIN RESPONSE Insulin Suppression During Exercise GLIMEPIRIDE GLIBENCLAMIDE

Advantages of Glimepiride (Over other sulphonylureas) Single daily dosing Comparable hypoglycaemic side effect profile to glipizide Safer in the presence of cardiac disease (SU-receptor –ve) Peripheral action conserves endogenous insulin Safer to use in the physically active

Disadvantages of Glimeperide Impact on glycosylated haemoglobin variable. Dosage: 1mg – 8mg per day

Glibenclemide 2.5mg twice a day to 10mg twice a day Glipizide 2.5mg twice a day Gliciazide 40mg twice a day to 160mg twice a day 15 minutes Before meals

Rosiglitazone & Pioglitazone Activate nuclear peroxisome proliferator activated receptor gamma (PPAR-γ) Increased insulin receptors in adipocytes & hepatocytes Increased Fatty Acid Translocase GLUT-1 and GLUT-4 proteins

Thiazolindinediones Partial mimics of insulin actions, may bind insulin receptor or act through the peroxisomal proliferator activated receptor γ Metabolized with a long half life

LBD- ligand binding region DBD- DNA binding region CREB-cyclic AMP response element binding protein CBP- CREB binding protein P/CAF - P300/ CBP associated factor SRC1- steroid receptor coactivator1

Special Consideration Hepatic Impairment Therapy should not be initiated if the patient exhibits clinical evidence of active acute or chronic liver disease of increased serum transaminase levels Fatty liver per se is not a contraindication

Thiazolidinediones- the impact Reduction in white adipose tissue Reduced Triglycerides Increase in brown adipose tissue- weight gain Increased LDL(10-15%) – buoyant fraction Oedema

Thiazolidinediones- The Advantages Important second / third line drug Monotherapy Potential single daily dose with Pioglitazone Lowered blood pressure No Hypoglycaemia Progressive rise in HDL levels

Thiazolidinediones-The Advantages(contd) Potential reduced microalbuminuria Reduced Vascular Intimal Thickening (impact on macrophage function) Combined effectively with insulin Safe in moderately severe renal failure

Rosiglitazone: Combination with Insulin HbA1c was decreased by 0.6 and 1.2% compared with an increase of 0.1% in the placebo group. Over half of patients receiving the higher dose of rosiglitazone had a decrease of  1% in HbA1c .

Thiazolidinediones- the disadvantages Potential weight gain (2-4 kg) LDL elevation (Mainly over 1st 2 months) Oedema Worsens Osteoporosis Containdicated in Grave’s Ophthalmopathy, Macular Oedema Occasional fluid overload (therefore avoid in Ischemic heart Disease)

Rosiglitazone vs Pioglitazone adversity profile A slightly higher prevalence of volume overload incidents with Rosiglitazone More evidence of vascular endothelial improvement with Pioglitazone

Alpha Glucosidase inhbitors Work on the brush border of the intestine cause carbohydrate malabsorption Advantages: Selective for postprandial hyperglycaemia No hypoglycaemic symptoms Disadvantages: Abdominal Distension and flatus Only effective in mild hyperglycaemia

Acarbose- 25 mg to 50mg thrice a day Miglitol- 25mg to 100mg thrice a day Voglibose- 0.2 to 0.3 mg thrice a day

Contraindications an inflammatory bowel disease, such as ulcerative colitis or Crohn's disease; or any other disease of the stomach or intestines ulcers of the colon Intestinal Obstruction kidney disease.

Incretin concept Insulin secretion dynamics is dependent on the method of administration of glucose Intravenous glucose gives a marked first and second phase response Oral glucose gives less marked first and second phase insulin response, but a prolonged and higher insulin concentration

Insulin secretion profiles Glucose given orally Insulin concentration Glucose given intravenously 0 10 20 30 40 50 60 70 80 90 minutes

Iso-glycaemic profiles Incretin effect Glucose given orally Insulin concentration Glucose given intravenously to achieve the same profile 0 10 20 30 40 50 60 70 80 90 minutes

What are the incretins? GIP: Glucose-dependent insulinotrophic polypeptide Small effect in Type 2 diabetes. GLP-1(glucagon-like peptide 1) augmented in the presence of hyperglycaemia. Action less at euglycaemia and in normal subjects. Pituitary Adenylate Cyclase Activating Peptide (PACAP)

History of GLP-1 Discovered as proglucagon gene product Insulinotropic action of incretins confirmed Incretin and enteroinsular axis further defined Normalisation of BG in type 2 diabetes Incretin defined ‘Enteroinsular axis’ named Receptor cloned History of GLP-1 In 1930, Zunz and LaBarre described an intestinal extract that could produce hypoglycaemia. In a separate paper, LaBarre used the term ‘incretin’ to describe activity in the gut that might initiate pancreatic endocrine secretions. In 1963, McIntyre suggested that a humoral substance was released from the jejunum during glucose absorption, acting in concert with glucose to stimulate insulin release from pancreatic ß-cells. In 1969, Unger and Eisentraut referred to the gut—pancreas association as the enteroinsular axis. In 1979, this axis was subsequently described as involving nutrient, neural, and hormonal signals from the gut to the pancreatic islet cells that secrete insulin, glucagon, and somatostatin. Incretins acting on this pathway must be secreted in response to nutrient stimuli and must stimulate glucose-dependent insulin secretion (Creutzfeldt 1979). In the early 1980s, GLP-1, was discovered to be a product of the proglucagon gene. The GLP-1 receptor was initially cloned in 1992 by Bernard Thorens in the rat pancreatic islet cell (Thorens 1992). A year later, a human pancreatic GLP-1 receptor with 90% homology to the amino acid sequence of the rat receptor was cloned (Dillon et al. 1993, Graziano et al. 1993, Thorens et al. 1993). In 1993, Nauck et al. published the findings of a study investigating the blood glucose lowering potential of GLP-1 in ten type 2 diabetes patients with unsatisfactory metabolic control from diet or sulphonylurea treatment. Continuous intravenous (i.v.) infusion of GLP-1 during a fasting state significantly increased insulin and C-peptide secretion while reducing glucagon secretion. Plasma glucose returned to normal fasting glucose concentrations within 4 hours of GLP-1 administration: no such decrease was observed during placebo infusion. Once normal fasting plasma glucose levels were attained, insulin secretion and plasma glucose stabilised despite ongoing infusion of GLP-1, highlighting its glucose-dependent action. Despite its demonstrated blood glucose lowering capabilities, the short half-life of native GLP-1 is a major obstacle to its use in clinical practice. Thus, long-acting GLP-1 analogues with a prolonged action are in development. Liraglutide was patented in 1996. A pubmed search for ‘GLP-1’ and glucagon-like peptide-1 revealed just 145 publications before 1992 (the earliest publication on pubmed was reported in 1982). However, the increased interest in and potential of GLP-1 as a treatment for diabetes is reflected by the rapid increase in publications in more recent years. Between the start of 1993 and the end of 2003, 1365 publications on GLP-1 were documented on pubmed. References Zunz, LaBarre. Arch Int Phsyiol Biochim 1929;31:20–44. LaBarre, Still. Am J Physiol 1930;91:649–653. McIntyre et al.: Lancet 1964; 2:20-21. Unger, Eisentraut. Arch Intern Med 1969;123:261–266. Creutzfeld. Diabetologia 1979;16:75–85. Thorens. Prac Natl Acad Sci USA 1992;89:8641–8645. Dillon et al. Endocrinology 1993;133:1907–1910. Graziano et al. Biochem Biophys Res Commun 1993;196:141–146. Thorens et al. Diabetes 1993;42:1678–1682. Nauck et al. Diabetologia 1993;36:741–744. Kieffer, Habener. Endocrine Reviews 1999;20:876–913 1930 1960 1970 1980 1990 2000

Proglucagon genome: pancreas and gut MAJOR PROGLUCAGON FRAGMENT 1 30 33 GRPP GLUCAGON IP-1 GLP-1 IP-2 GLP-2 Partial activity Full activity Inhibitory 1…….....37 GLUCAGON 7……..37 7…….36

GLP-1 localisation Cleaved from proglucagon in intestinal L-cells (and neurons in hindbrain/hypothalamus) Secreted in response to meal ingestion Cleared via the kidneys

GLP-1 Modes of Action in Humans Upon ingestion of food… Stimulates glucose-dependent insulin secretion Suppresses glucagon secretion DISCUSSION POINTS: Upon ingestion of meals containing carbohydrates and fats, GLP-1 is secreted from the L-cells in the intestine. This secretion of GLP-1 sets off a collection of actions which work in concert to help regulate glucose homeostasis: Glucose dependent enhancement of insulin secretion Suppression of inappropriately high glucagon secretion Slowing of gastric emptying Exogenous GLP-1 reduced food intake, and improved insulin sensitivity, in both animal studies and a 6-week study in patients with type 2 diabetes. In animal studies, exogenous GLP-1 increased beta-cell mass through beta-cell proliferation and neogenesis. SLIDE BACKGROUND: [This is an animated slide] Slows gastric emptying GLP-1 is secreted from the L-cells in the intestine Reduces food intake Long term effects demonstrated in animals… This in turn… Increases beta-cell mass and maintains beta-cell efficiency

Mean (SE) GLP-1 (pmol/L) Postprandial GLP-1 Levels are Decreased in Subjects With IGT and Type 2 Diabetes Meal NGT subjects IGT subjects T2DM patients 20 * * * * * DISCUSSION POINTS: These data show that postprandial GLP-1 concentrations are reduced in subjects with type 2 diabetes and impaired glucose tolerance (IGT). The top line represents GLP-1 concentrations in subjects with normal glucose tolerance (NGT). GLP-1 concentrations are statistically significantly reduced in patients with type 2 diabetes compared to NGT subjects from t=60 min to 150 min. SLIDE BACKGROUND: Fifty-four subjects with type 2 diabetes (BMI 30.2 kg/m2, age 55.9 y, A1C 8.4%), 15 IGT (BMI 35.0 kg/m2, age 55.3 y, A1C 6.1%), and 33 NGT (BMI 29.6 kg/m2, age 56.2 y, A1C 5.9%). All antidiabetic medications were discontinued 3 days prior to study during which time subjects were fed a mixed meal (t=0) and blood samples taken for 6 subsequent hours. Plasma concentration of GLP-1 were measured by means of RIA specific for C-terminus of GLP-1, which measures the sum of GLP-1 (7-36) amide and its metabolite GLP-1 (9-36) amide. * 15 * Mean (SE) GLP-1 (pmol/L) 10 * 5 60 120 180 240 Time (min) * P <0.05 between T2DM and NGT group. Data from: Toft-Nielsen M, et al. J Clin Endocrinol Metab 2001; 86:3717-3723

Effect of GLP-1 Infusion on Glucose Concentration in Patients With Type 2 Diabetes (Previously on OHAs) Saline GLP-1 Non-diabetic Controls 16 14 DISCUSSION POINTS: Infusion of GLP-1 overnight and during the day resulted in a reduction in fasting and postprandial glucose concentrations compared with placebo in patients with type 2 diabetes. Plasma glucose profiles appeared near-normal when compared with non-diabetic controls SLIDE BACKGROUND: Patients with type 2 DM (n=8) in a 3-way crossover study treated with: 19-h continuous IV infusion of GLP-1 (1.2 pmol/kg/min from 2200 to 1700) Overnight IV infusion of GLP-1 (1.2 pmol/kg/min from 2200 to 0730) IV Saline (from 2200 to 1700) Non-diabetic controls (n=6) were studied on one occasion without GLP-1 infusion. Three standard meals during the day (breakfast at 0800, lunch at 1200, and snack at 1500). Blood sampled intermittently throughout the study for plasma glucose and insulin concentrations. 12 Glucose (mmol/L) 10 8 6 4 2 Breakfast Lunch Snack 22.00 24.00 02.00 04.00 06.00 08.00 10.00 12.00 14.00 16.00 Clock Time (h) GLP-1 IV infusion (1.2 pmol/kg/min) Data from: Rachman J, et al. Diabetologia 1997; 40: 205-211

Now for the bad News…………..

GLP-1 is short-acting Blood glucose profiles Control After 7 days 24-h/day GLP-1 s.c. infusion 16-h/day GLP-1 s.c. infusion 100 200 300 400 04 06 08 10 12 14 16 18 20 22 00 02 Blood Glucose (mg/dl) Time Blood glucose profiles Key point here is that GLP-1 must be present 24-h per day to keep glucose levels low. This study was a randomised study, where the patients were treated with GLP-1 (IV infusion) for 7 days. The patients in the upper figure received GLP-1 for 16 hours (blue bar) a day. The plasma glucose was lowered immediately, but when the infusion was stopped at 11 p.m., the plasma glucose started to increase again. The patients in the lower figure received treatment for 24 hours a day. The plasma glucose is kept low also during the night. It can be concluded that GLP-1 need to be maintained continuously in order to maintain a reasonable glycaemic control. Mention the key enzyme DPPIV (see next slide) and possible renal clearance responsible for this short action of GLP-1. Upper plot 8 ng/kg/min for 16 hours on seven consecutive days Lower plot 8 ng/kg/min for 24 hours on seven consecutive Control After 7 days Modified from J Larsen et al: Diabetes Care 2001; 24:1416-1421

GLP-1 DPP IV 7 His Ala Glu Gly Thr Phe Thr Ser Asp Val Ser Lys Ala Ala Gln Gly Glu Leu Tyr Ser Glu Phe Ile Ala Trp Leu Val Lys Gly Arg Gly GLP-1 is modified this way in order to get a long-acting compound. The protract is similar to NN304 (our long-acting insulin analogue) 37 NH2 Native GLP-1 has short duration of action (t½=2.6 minutes) when given intravenously

Native GLP-1 is rapidly degraded by DPP-IV Human ileum, GLP-1 producing L-cells Capillaries, DiPeptidyl Peptidase-IV (DPP-IV) Adapted from: Hansen et al. Endocrinology 1999:140(11):5356-5363

DPP-IV action GIP GLP-1 (biologically [1–42] [7–36 amide] active) GIP GLP-1 (biologically [3–42] [9–36 amide] inactive)

So is that a dead-end for drug development in this area ………….?

DPP-IV (DPP4) inhibitors 7 His Ala Glu Gly Thr Phe Thr Ser Asp Val Ser Lys Ala Ala Gln Gly Glu Leu Tyr Ser Glu Phe Ile Ala Trp Leu Val Lys Gly Arg Gly 37 NH2

Dipeptyl- peptidase inhibitors Sitagliptin Vildagliptin Saxagliptin Septagliptin Allogliptin

Sitagliptin - Overview 1st approved member of a new class of OAHA - DPP-4 inhibitor Potent, highly selective, reversible and competitive inhibitor of DPP- 4 enzyme Approved by the FDA on October 17 2006. EU approval March 2007

Mechanism of Action of Sitagliptin Release of active incretins GLP-1 and GIP  Blood glucose in fasting and postprandial states Ingestion of food  Glucagon (GLP-1)  Hepatic glucose production GI tract DPP-4 enzyme Inactive GLP-1 X Sitagliptin (DPP-4 inhibitor)  Insulin (GLP-1 and GIP) Glucose- dependent Glucose dependent Pancreas GIP β cells α cells  Glucose uptake by peripheral tissues Mechanism of Action of Sitagliptin This slide shows the mechanism of action of sitagliptin. The incretin hormones GLP-1 and GIP, as described earlier in this presentation, are released by the intestine throughout the day, and levels are increased in response to a meal. The activity of GLP-1 and GIP is limited by the DPP-4 enzyme, which rapidly inactivates incretin hormones. As a DPP-4 inhibitor, sitagliptin is believed to exert its actions in patients with type 2 diabetes by slowing the inactivation of incretin hormones. Concentrations of the active intact hormones are increased by sitagliptin, thereby increasing and prolonging the action of these hormones, which ultimately lowers blood glucose in the fasting and postprandial states. Purpose: To illustrate the mechanism of action for sitagliptin. Take-away: The concentrations of GLP-1 and GIP are increased by sitagliptin, thereby increasing and prolonging the actions of these hormones. Incretin hormones GLP-1 and GIP are released by the intestine throughout the day, and their levels increase in response to a meal. Concentrations of the active intact hormones are increased by sitagliptin, thereby increasing and prolonging the actions of these hormones. 30 Reference 1. Data on file.

Clinical Pharmacology of Sitagliptin: Pharmacokinetics and Drug Interactions Tmax (median): 1 to 4 hours postdose Apparent t½ (mean): 12.4 hours Metabolism: approximately 79% excreted unchanged in urine Based on in vitro data, sitagliptin does not inhibit CYP isozymes CYP3A4, 2C8, 2C9, 2D6, 1A2, 2C19, or 2B6 or induce CYP3A4 Clinical Pharmacology of Sitagliptin: Pharmacokinetics and Drug Interactions A single oral dose of sitagliptin 100 mg is rapidly absorbed, with median peak plasma concentrations occurring 1 to 4 hours postdose. The apparent mean terminal half-life (t1/2) after a 100-mg oral dose is 12.4 hours. With regard to metabolism, sitagliptin is primarily eliminated unchanged (approximately 79%) in the urine. In drug interaction studies, sitagliptin did not have clinically meaningful effects on the pharmacokinetics of metformin, glyburide, simvastatin, rosiglitazone, warfarin, or oral contraceptives. Finally, based on in vitro data, sitagliptin does not inhibit CYP isozymes CYP3A4, 2C8, 2C9, 2D6, 1A2, 2C19, or 2B6 or induce CYP3A4. On the topic of drug interactions, there are no known clinically meaningful drug interactions with sitagliptin. Purpose: To present an overview of the clinical pharmacology of sitagliptin. Take-away: Sitagliptin has no clinically meaningful drug interactions. 33 Reference 1. Data on file.

Upper Respiratory Tract Infection 6.8 6.7 Nasopharyngitis 4.5 3.3 Adverse Experiences Reported in ≥3% of Patients and Greater than Placeboa Sitagliptin 100 mgc n = 1082 Placeboc n = 778 Upper Respiratory Tract Infection 6.8 6.7 Nasopharyngitis 4.5 3.3 Diarrhea 3.0 2.3 Adverse Experiences Reported in ≥3% of Patients and Greater than Placebo Safety profile assessment of JANUVIA was performed in the prespecified pooled analysis of 4 placebo-controlled clinical studies: one 18-week monotherapy study, one 24-week monotherapy study, and in combination with either metformin (24-week study) or pioglitazone (24-week study). The adverse events reported in ≥3% of patients treated JANUVIA™ with and more commonly than with placebo were upper respiratory tract infection, nasopharyngitis, and diarrhea. In a 24-week placebo-controlled study of JANUVIA 100 mg once daily in combination with glimepiride or with glimepiride and metformin (JANUVIA, n=222; placebo, n=219), the adverse experiences reported regardless of causality assessment in ≥5% of patients treated with JANUVIA and more commonly than in patients treated with placebo were: hypoglycemia (JANUVIA, 12.2%; placebo, 1.8%), nasopharyngitis (6.3%, 4.6%), and headache (5.9%, 2.3%). In a 24-week placebo-controlled factorial study of initial therapy with JANUVIA 100 mg in combination with metformin 1000 mg or 2000 mg per day (administered at JANUVIA 50 mg/ metformin 500 mg or 1000 mg twice daily), the adverse experiences reported (regardless of investigator assessment of causality) in ≥5% of patients treated with JANUVIA plus metformin (n=372) and more commonly than in patients treated with metformin alone (n=364) were upper respiratory tract infection (JANUVIA plus metformin, 6.2%; metformin, 5.2%) and headache (5.9%; 3.8%). The incidence of hypoglycemia was 1.6% in patients given JANUVIA in combination with metformin and 0.8% in patients given metformin alone. Presenter: if the content of this slide does not match the local product label for JANUVIA, please adapt this slide to provide corresponding information about adverse experiences in the local approved label. Purpose: To review the adverse events profile for JANUVIA™† (sitagliptin). Take-away: Upper respiratory tract infection, nasopharyngitis, and diarrhea were the adverse experiences occurring more frequently with JANUVIA than with placebo. †Trademark of Merck & Co., Inc., Whitehouse Station, NJ, USA 48 †Trademark of Merck & Co., Inc., Whitehouse Station, NJ, USA Reference 1. Data on file.

Sita-gliptin

Summary – Safety + Tolerability 7 specific AEs Chills Naso-pharyngitis Meniscus lesions Nasal congestion Contact dermatitis Osteoarthritis Tremor Pooled safety. Stein et al. ADA 2007

Sitagliptin AUC0–inf Increased With Decreasing Creatinine Clearance Dose-Adjusted (to 50 mg) AUC, μM/h 4 8 12 16 20 24 28 Creatinine Clearance, mL/min 10 30 50 70 90 110 130 150 170 190 210 230 AUC GMR increase <2-fold when CrCl >50 mL/min Dose adjustments <30 mL/min: ¼ dose (25mg OD) 30–50 mL/min: ½ dose (50mg OD) >50 mL/min: full dose (100mg OD) JANUVIA™ (sitagliptin) in Patients With Renal Insufficiency This slide summarizes the rationale for dose adjustments in patients with moderate to severe renal insufficiency. A single-dose, open-label study evaluated the pharmacokinetics of JANUVIA (50 mg dose) in patients with varying degrees of chronic renal insufficiency compared with healthy subjects. In addition, the effects of renal insufficiency on JANUVIA pharmacokinetics in patients with type 2 diabetes and mild or moderate renal insufficiency were assessed using population pharmacokinetic analyses. Patients with mild renal insufficiency (creatinine clearance [CrCl]: 50 to <80 mL/min) did not have a clinically relevant increase in the plasma concentration of JANUVIA compared with normal healthy control individuals. An approximately 2-fold increase in the plasma area under the curve (AUC) of JANUVIA was observed in patients with moderate renal insufficiency (CrCl: 30 to <50 mL/min), and an approximately 4-fold increase was observed in patients with severe renal insufficiency (CrCl: <30 mL/min) and in patients with end-stage renal disease (ESRD) on hemodialysis compared with normal healthy control subjects. To achieve plasma concentrations of JANUVIA similar to those in patients with normal renal function, lower dosages are recommended in patients with moderate and severe renal insufficiency, as well as in patients with ESRD requiring hemodialysis or peritoneal dialysis. Note: A dosage adjustment is recommended based on the pharmacokinetic profile of JANUVIA, to ensure that patients receive the appropriate levels of drug required to achieve the efficacy of JANUVIA.

Patients With Renal Insufficiency o n s 2; 12.3 Patients With Renal Insufficiency Renal Insufficiency Mild Moderate Severe and ESRD* Increase in Plasma AUC of Sitagliptin† ~1.1 to 1.6-fold increase‡ ~2-fold increase ~4-fold increase Recommended Dose 100 mg no dose adjustment required 50 mg 25 mg Patients With Renal Insufficiency To achieve plasma concentrations of sitagliptin similar to those in patients with normal renal function, lower dosages are recommended in patients with moderate and severe renal insufficiency, as well as in patients with ESRD requiring hemodialysis or peritoneal dialysis. A dosage adjustment is recommended based on the pharmacokinetic profile of JANUVIA™ (sitagliptin phosphate), to ensure that patients receive the appropriate levels of drug required to achieve the efficacy of JANUVIA. This slide summarizes the dose adjustments in patients with moderate to severe renal insufficiency. A single-dose, open-label study evaluated the pharmacokinetics of JANUVIA (50 mg dose) in patients with varying degrees of chronic renal insufficiency compared with healthy subjects. In addition, the effects of renal insufficiency on sitagliptin pharmacokinetics in patients with type 2 diabetes and mild or moderate renal insufficiency were assessed using population pharmacokinetic analyses. Patients with mild renal insufficiency (creatinine clearance [CrCl]: 50 to <80 mL/min) did not have a clinically relevant increase in the plasma concentration of sitagliptin compared with normal healthy control individuals. An approximately 2-fold increase in the plasma area under the curve (AUC) of sitagliptin was observed in patients with moderate renal insufficiency (CrCl: 30 to <50 mL/min), and an approximately 4-fold increase was observed in patients with severe renal insufficiency (CrCl: <30 mL/min) and in patients with end-stage renal disease (ESRD) on hemodialysis compared with normal healthy control subjects.

Sitagliptin Has a Weight Neutral Profile Monotherapy studies No increase in body weight from baseline with sitagliptin compared with a small decrease in the placebo group Add-on to metformin A similar decrease in body weight for both treatment groups Add-on to pioglitazone No significant difference in body weight between treatment groups Noninferiority vs Sulfonylurea A significant reduction in body weight with sitagliptin versus weight gain with glipizide Sitagliptin Has a Generally Weight Neutral Profile Body weight did not increase from baseline with sitagliptin in either the 18-week or 24-week monotherapy study, compared with a small reduction in the body weight of patients given placebo.1,2 A slight but similar decrease in body weight of patients was observed in both treatment groups of the add-on study with metformin.2 There was no significant difference between sitagliptin and placebo in body weight change in the add-on study with pioglitazone.3 Overall, sitagliptin appeared to have a neutral effect on body weight.4 Purpose: To review the body weight profile for sitagliptin. Take-away: Sitagliptin has a generally weight neutral profile. 46 Reference 1. Aschner P, Kipnes MS, Lunceford JK, Sanchez M, Mickel C, Williams-Herman, DE, for the Sitagliptin Study 021 Group. Effect of the dipeptidyl peptidase-4 inhibitor sitagliptin as monotherapy on glycemic control in in patients with type 2 diabetes. Diabetes Care. 2006;29:2632–2637. 2. Charbonnel B, Karasik A, Liu J, Wu M, Meininger G, for the Sitagliptin Study 020 Group. Efficacy and safety of the dipeptidyl peptidase-4 inhibitor sitagliptin as monotherapy on glycemic control in in patients with type 2 diabetes. Diabetes Care. 2006;29:2632–2637. 3. Rosenstock J, Brazg R, Andryuk PJ, Lu K, Stein, P, for the Sitagliptin Study 019 Group. Efficacy and safety of the dipeptidyl peptidase-4 inhibitor sitagliptin added to ongoing pioglitazone therapy in patients with type 2 diabetes: a 24-week, multicenter, randomized, double-blind, placebo-controlled, parallel-group study. Clin Ther. 2006;28:1556–1568. 4. Nauck MA, Meininger G, Sheng D, et al, for the Sitagliptin Study 024 Group. Efficacy and safety of the dipeptidyl peptidase-4 inhibitor, sitagliptin, compared with the sulfonylurea, glipizide, in patients with type 2 diabetes inadequately controlled on metformin alone: a randomized, double-blind, non-inferiority trial. Diabetes Obes Metab. 2007;9:194–205.

Review of Safety and Tolerability Saxagliptin Review of Safety and Tolerability Now that we’ve reviewed efficacy and safety data for some of the key Onglyza™ studies, let’s review general safety for the Phase 3 program

Saxagliptin: Incidence of Adverse Events Overall Incidence of Adverse Events Was Similar to Placebo Pooled Analysis of Adverse Reactions Occurring in ≥5% of Patients and More Commonly Than Placebo Hypersensitivity-related events (such as urticaria and facial edema) were reported in 1.5% who received Saxagliptin 5 mg, Saxagliptin 2.5 In Monotherapy and Add-On Therapy Studies* Percent of Patients Saxagliptin 5 mg (N=882) Placebo (N=799) Upper respiratory tract infection 7.7% 7.6% Urinary tract infection 6.8% 6.1% Headache 6.5% 5.9% When added on to key OADs (MET, the SU glyburide, or a TZD) or as monotherapy, Onglyza™ demonstrated a rate of adverse events similar to placebo For all add-on combination and monotherapy studies, the overall incidence of adverse events was 72% for Onglyza 5 mg vs 71% for placebo This table shows the adverse events reported by 5% or more of patients (and more commonly than placebo) in a pooled analysis of 2 monotherapy studies and the 3 add-on combination studies of Onglyza, including the Onglyza add-on to MET combination study that we have been discussing in this presentation In patients treated with Onglyza 2.5 mg, headache (6.5%) was the only adverse reaction occurring in ≥5% of patients and more commonly than placebo In this pooled analysis, less common adverse reactions that were reported in ≥2% of patients treated with Onglyza 5 mg or Onglyza 2.5 mg and ≥1% more frequently compared to placebo, respectively, included: sinusitis (2.6% and 2.9% vs 1.6%, respectively); abdominal pain (1.7% and 2.4% vs 0.5%); gastroenteritis (2.3% and 1.9% vs 0.9%); and vomiting (2.3% and 2.2% vs 1.3%) Hypersensitivity-related events (such as urticaria and facial edema) were reported in 1.5%, 1.5% and 0.4% of patients who received Onglyza 5 mg, Onglyza 2.5 mg, and placebo, respectively Onglyza was weight and lipid neutral *Prespecified pooled analysis of 2 monotherapy studies, the add-on to MET study, the add-on to the SU glibenclamide study, and the add-on to a TZD study; 24-week data regardless of glycemic rescue. Reference Onglyza package insert. Bristol-Myers Squibb Company and AstraZeneca Pharmaceuticals LP; 2009.

Incidence of Adverse Events in Initial Combination With MET Adverse Reaction Occurring in ≥5% Patients and More Commonly Than MET Plus Placebo In Initial Combination With MET Study* Percent of Patients Saxagliptin 5 mg + MET (N=320) MET + Placebo (N=328) Headache 7.5% 5.2% Nasopharyngitis 6.9% 4.0% The overall incidence of adverse events in those medication-naive individuals receiving Onglyza 5 mg as initial combination with MET compared with those receiving placebo plus MET was 55% vs 59%, respectively1 This table shows the adverse events reported by 5% or more of patients in a study of Onglyza 5 mg as initial combination therapy with MET, which included headache (7.5% vs 5.2% with MET plus placebo) and nasopharyngitis (6.9% vs 4.0% with MET plus placebo)2 *Metformin was initiated at a starting dose of 500 mg daily and titrated up to a maximum of 2000 mg daily. Jadzinsky M et al. Diabetes Obes Metab. 2009;11:611-622. References Jadzinsky M, Pfützner A, Paz-Pacheco E,et al; for the CV181-039 Investigators. Saxagliptin given in combination with metformin as initial therapy improves glycaemic control in patients with type 2 diabetes compared with either monotherapy: a randomized controlled trial. Diabetes Obes Metab. 2009;11:611-622. Onglyza package insert. Bristol-Myers Squibb Company and AstraZeneca Pharmaceuticals LP; 2009.

Saxagliptin: Discontinuation of Therapy Due to Adverse Events Discontinuation of therapy due to adverse events occurred in 3.3% and 1.8% of patients receiving Saxagliptin and placebo, respectively There was a dose-related mean decrease in absolute lymphocyte count observed with Saxagliptin Most Common Adverse Events Associated With Discontinuation of Therapy* Percent of Patients Saxagliptin 5 mg (N=882) Saxagliptin 2.5 mg (N=882) Comparator (N=799) Lymphopenia 0.5% 0.1% 0.0% Rash 0.3% 0.2% Blood creatinine increase Blood creatine phosphokinase increase Discontinuation of therapy due to adverse events occurred in 3.3% and 1.8% of patients receiving Onglyza™ and placebo, respectively This slide lists adverse events associated with discontinuation that were reported in at least 2 patients treated with Onglyza. Among the adverse events listed, rates were generally similar between those taking Onglyza and those on placebo There was a dose-related mean decrease in absolute lymphocyte count observed with Onglyza. The clinical significance of this decrease is unknown *Reported in at least 2 patients treated with Saxagliptin Reference Onglyza package insert. Bristol-Myers Squibb Company and AstraZeneca Pharmaceuticals LP; 2009.

Drug Interactions and Use in Specific Populations Saxagliptin should be limited to 2.5 mg when coadministered with a strong CYP3A4/5 inhibitor (e.g., atazanavir, clarithromycin, indinavir, itraconazole, ketoconazole, nefazodone, nelfinavir, ritonavir, saquinavir, and telithromycin). Use in Specific Populations Pregnant and Nursing Women: There are no adequate and well-controlled studies in pregnant women Pediatric Patients: Safety and effectiveness of Saxagliptin in pediatric patients have not been established. Drug Interactions Because ketoconazole, a strong CYP3A4/5 inhibitor, increased saxagliptin exposure, the dose of ONGLYZA™ should be limited to 2.5 mg when coadministered with a strong CYP3A4/5 inhibitor (e.g., atazanavir, clarithromycin, indinavir, itraconazole, ketoconazole, nefazodone, nelfinavir, ritonavir, saquinavir, and telithromycin) Use in Specific Populations Patients With Renal Impairment: The dose of ONGLYZA is 2.5 mg once daily for patients with moderate or severe renal impairment, or with end-stage renal disease (ESRD) requiring hemodialysis (creatinine clearance [CrCl] ≤50 mL/min). ONGLYZA should be administered following hemodialysis. ONGLYZA has not been studied in patients undergoing peritoneal dialysis. Assessment of renal function is recommended prior to initiation of ONGLYZA and periodically thereafter Pregnant and Nursing Women: There are no adequate and well-controlled studies in pregnant women. ONGLYZA, like other antidiabetic medications, should be used during pregnancy only if clearly needed. It is not known whether saxagliptin is secreted in human milk. Because many drugs are secreted in human milk, caution should be exercised when ONGLYZA is administered to a nursing woman Pediatric Patients: Safety and effectiveness of ONGLYZA in pediatric patients have not been established Reference Onglyza package insert. Bristol-Myers Squibb Company and AstraZeneca Pharmaceuticals LP; 2009.

Saxagliptin: Renal Impairment Mild Impairment, creatinine clearance [CrCl] ≤50 mL/min: No dosage adjustment Moderate or severe renal impairment, or with end-stage renal disease (ESRD) requiring hemodialysis (creatinine clearance [CrCl] ≤50 mL/min). Saxagliptin 2.5 mg is recommended. Saxagliptin should be administered following hemodialysis when used in that scenario. Saxagliptin has not been studied in patients undergoing peritoneal dialysis. Assessment of renal function is recommended prior to initiation of Saxagliptin and periodically thereafter.

Saxagliptin: Hepatic Impairment In subjects with hepatic impairment (Child-Pugh classes A, B, and C) Mean Cmax and AUC of saxagliptin were up to 8% and 77% higher, respectively, compared to healthy matched controls following administration of a single 10 mg dose of saxagliptin. The corresponding Cmax and AUC of the active metabolite were up to 59% and 33% lower, respectively, compared to healthy matched controls. These differences are not considered to be clinically meaningful. No dosage adjustment is recommended for patients with hepatic impairment

Cardiovascular events: Saxagliptin controlled Phase 2b/3 pooled population Time to onset of first primary Major Adverse Cardiovascular Event (MACE)* All saxagliptin Control 24 37 50 63 76 89 102 115 128 1 2 3 4 5 Weeks First adverse event (%) There are currently no long-term data regarding the association between Onglyza and CV events. The long-term CV risk-benefit of Onglyza continues to be evaluated.1 • Experience in patients with congestive heart failure of New York Heart Association class I-II is limited, and there is no experience in clinical studies with Onglyza in class III-IV4 1Onglyza. European Public Assessment Report. Scientific Discussion. Published 06/07/09. European Medicines Agency. Accessible from http://www.emea.europa.eu/humandocs/Humans/EPAR/onglyza/onglyza.htm. In a post-hoc analysis of pooled Phase 2b/3 studies, there was no evidence of a cardiovascular safety signal in individuals receiving saxagliptin In December 2008, the FDA issued a guidance document to recommend that all new drugs developed for the treatment of type 2 diabetes to show that they do not increase the risk of cardiovascular events. The recommendation emerged after concerns were raised about the cardiovascular safety of drugs in this field, especially the thiazolidinediones (TZDs). The trials for saxagliptin were complete when the FDA issued the guidance document, therefore the cardiovascular safety analyses were performed post-hoc. The time to onset of first Primary MACE in the Phase 2b/3 Pooled Population is shown in this figure. These data indicate that there is no increased risk of Primary MACE in saxagliptin-treated subjects during both the short-term and long-term periods of the clinical studies. Definition: Primary MACE was defined as stroke (cerebrovascular accidents), MI, and CV death. Patients at risk Control 1,251 935 860 774 545 288 144 123 102 57 All saxagliptin 3,356 2,615 2,419 2,209 1,638 994 498 436 373 197 * Primary MACE was defined as was defined as stroke (cerebrovascular accidents), MI, and CV death

Comparing the Gliptins Sitagliptin Vildagliptin Saxagliptin Dosing OD BD OD Renal Failure Approved Not Approved Approved Hepatic Failure No info No info Safe With Insulin Not Approved Approved Studies Pending On Bone Improved BMD? Unknown Unknown Infections Slight increase Neutral Neutral UTI, URI Cardiac Impact Reduced Neutral ?reduced CV mortality post ischaemic stunning

Which is the appropriate oral hypoglycaemic agent to use and when?

Determinants of OAD usage 1)Body Mass Index : Metformin, Gliptins BMI> 22kg/m2 2)Presence of GI symptoms: Sulpha, Gliptins, Glitazones 3)Renal Dysfunction: Gliptins,Glitazones(+/-),Sulpha (variable) 4) Aging Meglitinides, Gliptins(?) 5) Hepatic Dysfunction Nateglinide, Saxagliptin(?) 6) Compliance Gliptins, Glitazones, 7) Cost Metformin, Sulphas, Glitazones

Therapeutic Algorithm for Oral Hypoglycaemic Drugs…….Yesterday. Metformin Metformin Secretagogue Thiazolidinediones Alpha-Glucosidase ( BMI or WHR) inhibitors 3.Thiazolidinedione + Metformin 1. Metformin+ Secretagogue 2. Thiazolidinedione+ Secretagogue Triple Therapy

Therapeutic Algorithm for Oral Hypoglycaemic Drugs…….Today. Metformin Metformin Secretagogue Thiazolidinediones DPPV-4 inhibitor 2. DPPV-4 inhibitor+ Secretagogue 1. Metformin+ Secretagogue 3. DPPV-4 inhibitor + Metformin 4.Thiazolidinedione + Metformin Triple Therapy: A) M +Sec +DPPV B) M+Thia+DPPV Quadruple Therapy!!

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