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| Primary information |
|---|
| ID | 10506 |
| Therapeutic ID | Th1098 |
| Protein Name | Exenatide |
| Sequence | >Th1098_Exenatide
HGEGTFTSDLSKQMEEEAVRLFIEWLKNGGPSSGAPPPS
|
| Molecular Weight | 4186.6 |
| Chemical Formula | C184H282N50O60S |
| Isoelectric Point | 4.86 |
| Hydrophobicity | NA |
| Melting point | NA |
| Half-life | Mean terminal half-life is 2.4 hours. |
| Description | Derived from a compound found in the saliva of the Gila monster, a large lizard native to the southwestern United States. It is a functional analog of Glucagon-Like Peptide-1 (GLP-1) peptide. |
| Indication/Disease | Indicated as adjunctive therapy to improve glycemic control in patients with Type 2 diabetes mellitus who are taking metformin, a sulfonylurea, or a combination of both, but have not achieved adequate glycemic control. |
| Pharmacodynamics | Exenatide is an incretin mimetic, which has glucoregulatory effects. While it is has blood-sugar lowering actions alone, it can also be combined with other medications such as pioglitazone, metformin, sulfonylureas, and/or insulin to improve glucose control. The approved use of exenatide is with either sulfonylureas, metformin and thiazolinediones. The medication is injected twice per day using a pre-filled pen device. Typical human responses to exenatide plus eating include improvements in the initial rapid release of endogenous insulin, suppression of glucagon release by the pancreas, regulation of gastric empyting and reduced appetite; all behaviors more typical of individuals without blood sugar control problems. Exenatide is self-regulating in that in lowers blood sugar when levels are elevated but does not continue to lower blood sugar when levels return to normal, unlike with sulfonylureas or insulins. |
| Mechanism of Action | Exenatide is a functional analog of the human incretin Glucagon-Like Peptide-1 (GLP-1). Incretins enhance glucose-dependent insulin secretion and exhibit other antihyperglycemic actions following their release into the circulation from the gut. The GLP-1 system increases insulin secretion only in the presence of elevated plasma glucose levels, avoiding inappropriately high insulin levels during fasting. The drug also moderates peak serum glucagon levels during hyperglycemic periods following meals, but does not interfere with glucagon release in response to hypoglycemia. Secondary effects of drug administration reduces the rate of gastric emptying and decreases food intake, mitigating the potential severity of hyperglycemic events after meals. |
| Toxicity | In animal studies, exenatide was associated with fetal deformities of ribs and vertebrae as well as slowed growthLabel. In humans, uncontrolled hyperglycemia can be associated with an up to 25% risk of miscarriageLabel. No human studies in pregnancy have been performed with exenatide and so exenatide should only be prescribed in pregnancy if the benefit to the mother and fetus outweigh the risksLabel. In mice, exenatide is excreted in the milk at a concentration 2.5% of the plasma concentration though this data may not be applicable to humansLabel. The effect of exenatide on breastfed infants is also unknown and so the risk and benefit of breastfeeding while taking exenatide must be weighedLabel. There is no data for the use of exenatide in pediatric patientsLabel. Geriatric patients do not have different results for safety and efficacy of exenatide though caution should still be used in this group as they are at higher risk of renal impairment or other comorbidities that may affect the liklihood of adverse effectsLabel. No dosage adjustments are necessary for patients with creatinine clearance ≥50mL/min, though prescribing to patients with creatinine clearance 30-50mL/min should be done cautiouslyLabel. Exenatide is not recommended for patients with creatinine clearance <30mL/minLabel. Hepatic impairment is not expected to affect clearance of exenatide though no studies have been performed to confirm thisLabel. |
| Metabolism | Exenatide is filtered through the glomerulus before being degraded to smaller peptides and amino acids by dipeptidyl peptidase-4, metalloproteases, endopeptidase 24-11, amino proteases, and serine proteases. It is currently believed that the metalloproteases are responsible for most of the degradation of exenatide3. Exenatide is metabolised to small peptides <3 amino acids in length by enzymes in the kidney |
| Absorption | Exenatide reaches a peak plasma concentration in 2.1 hoursLabel. Because exenatide is administerd subcutaneously, the bioavailability is 1 |
| 28.3 L |
| Clearance | Apparent cl=9.1 L/hr |
| Categories | Hypoglycemic Agents |
| Patents Number | US5424286 |
| Date of Issue | 13-Jun-1995 |
| Date of Expiry | 1-Dec-2016 |
| Drug Interaction | NA |
| Target | Glucagon-like peptide 1 receptor |
| Brand Name | BYDUREON |
| Company | Amylin Pharmaceuticals |
| Brand Description | Amylin Pharmaceuticals |
| Prescribed For | BYDUREON is an extended-release formulation of exenatide, administered as an injection once every 7 days (weekly). BYDUREON is indicated as an adjunct to diet and exercise to improve glycemic control in adults with type 2 diabetes mellitus |
| Chemical Name | NA |
| Formulation | Exenatide is incorporated in an extended-release microsphere formulation containing the 50:50 poly(D,L-lactide-co-glycolide) polymer (37.2 mg per dose) along with sucrose (0.8 mg per dose). The powder must be suspended in the diluent prior to injection. The diluent for the BYDUREON vial is supplied in a prefilled syringe within each single-dose tray. The diluent for the BYDUREON Pen is contained within each single-dose pen. Each configuration contains sufficient diluent to deliver 0.65 mL. The diluent is a clear, colorless to pale-yellow solution composed of carboxymethylcellulose sodium (19 mg), polysorbate 20 (0.63 mg), sodium phosphate monobasic monohydrate (0.61 mg), sodium phosphate dibasic heptahydrate (0.51 mg), sodium chloride (4.1 mg), and water for injection. Sodium hydroxide may be added during manufacture of BYDUREON Pen for pH adjustment. |
| Physical Appearance | White to off-white powder that is available in a dosage strength of 2 mg exenatide per vial or per pen |
| Route of Administration | NA |
| Recommended Dosage | BYDUREON (2 mg per dose) should be administered once every 7 days (weekly). The dose can be administered at any time of day, with or without meals. |
| Contraindication | BYDUREON is not recommended as first-line therapy for patients who have inadequate glycemic control on diet and exercise. BYDUREON is not a substitute for insulin. BYDUREON should not be used in patients with type 1 diabetes or for the treatment of diabetic ketoacidosis, as it would not be effective in these settings. BYDUREON and BYETTA (exenatide) injection both contain the same active ingredient, exenatide, and therefore should not be used together. BYDUREON 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 pancreatitis while using BYDUREON. Other antidiabetic therapies should be considered in patients with a history of pancreatitis. |
| Side Effects | Possible thyroid tumors, including cancer, Allergic reaction Pancreatitis, Hypoglycemia |
| Useful Link 1 | Link |
| Useful Link 2 | NA |
| Remarks | NA |