The structure of Byetta is similar to that of GLP-1 and performs the same functions. Both promote decreased appetite (Wilson).
Dr. Wysham was an observer at a study conducted on 20 Rockwood diabetic patients who were taking conventional diabetic medication for their uncontrolled blood sugar (Wilson 2005). She was not informed about their glucose levels for several months after the tests began. About two-thirds of the respondents were given different injectible doses of Byetta to incorporate into their medication plan, while the rest were given placebos. All of them were instructed and trained to do the injections at certain times twice daily for a month. Then they were subjected to a physical exam. Dr. Wysham closely monitored their liver, kidney, blood counts, and other functions. She observed that the patients consistently lose weight while taking Byetta. The average respondent-patient lost 15 pounds in the duration of the study, 5 lost more than 20 and two, more than 40 (Wilson).
The results of the study led Dr. Wysham to believe that Byetta could slow down or even terminate the progression of diabetes before a patient requires insulin therapy (Wilson 2005). Injecting insulin and injecting Byetta had almost the same results. Byetta even made patients lose weight. This was the finding of a recently concluded six-month study. It compared patients who took insulin and patients who took Byetta both as injectibles and twice daily. Dr. Wysham commented that 102-week extension trials confirmed the trend. While she noted that Byetta does not work in all cases. But the results of an 82-week study showed that 62% of the respondents met clinically-established glucose standards, which they previously failed to meet. Dr. Wysham said that 90% of all diabetics are overweight and the benefits deriving from Byetta have understandably drawn diabetics to it. It is expensive yet compares with the price of other conventional diabetic drugs. It is covered by most health insurance plans. She estimated that Byetta costs $150 a month at wholesale (Wilson).
Eli Lilly's Byetta, indicated for Type 2 diabetes (Johnsen 2005).Its generic name is exenatide, considered an incretin mimetic agent. It imitates the action of insulin in the intestines in stimulating insulin production without the risk of hypoglycemia. This risk is associated with insulin injections. Byetta is the synthetic exendin-4 hormone from the saliva of the Gila monster. This lizard eats only four times a year. When not eating, its pancreas is inactive. When it does, the exendin-4 found in its saliva reactivates the pancreas. Byetta imitates the mechanisms of insulin, which is similar to extendin-4. Byetta remains in the blood system and works only when blood sugar levels are too high. Observers projected the sales of Byetta to exceed $800 million next year. Its manufacturer, Eli Lilly, was working for the approval of a long-acting release version last year. This new formulation was predicted to reach $1.5 billion in sales (Johnsen).
Exenatide injection is indicated only for Type-2 diabetes but not as a substitute for insulin (Ezzo and Ambizas 2006). The biggest clinical test of exenatide therapy investigated 733 patients who used exenatide with metformin and a sulfonylurea for 30 weeks. The most commonly observed adverse reaction was gastrointestinal in nature. The combination of xenatide and metformin did not increase the incidence of hypoglycemia. But there was a 3.3-14.4% increase when sulf0nylurea was added to exenatide (Ezzo and Ambizas).
In studies on the tolerability of exenatide when combined with current therapy, 7% of the respondents backed out because of nausea and vomiting (Ezzo and Ambizas 2006). Other common reactions were diarrhea, dizziness, headache and shaking. The patients lost an average of 4.9 pounds in the 30 weeks of study. Another study, which combined exenatide and insulin glargine, 1 in 10 withdrew because of the adverse effects of the combination. These effects were 57% nausea and 17% vomiting. As to effectiveness, studies showed that a combination of exenatide would result in 7% or less of A1C in 24 to 46% of patients with an initial A1C of more than 7%. Exenatide reduced fasting plasma glucose levels by 5 to 10 mg per dL. This did not increase weight. A pre-filled pen containing 60 doses of exenatide for a month would cost approximately $191 to 223. A vial of 10 ml of insulin glargine would cost approximately $69 for a month's use. And exenatide is sold as a sterile solution for subcutaneous injection at 250 mcg per mL. It is available in 1.2-mL prefilled pen and in 2.4-ml prefilled pen forms. This should be injected into the thigh, abdomen or upper arm. It should be refrigerated and protected from light. It should be disposed of 30 days after the first use. The first dosage must be injected subcutaneously two times daily within 60 minutes before the morning and evening meals, not after. The dose may be increased to 10 mcg twice daily after a month of treatment. When added to metformin, exenatide may be continued. When added to a sulfonylurea, the dose of sulfonylurea should be reduced to avoid or reduce the risk of hypoglycemia (Ezzo and Ambizas).
Exenatide injectible for Type-2 diabetes requires that the patient be educated in its use (Ezzo and Ambizas 2006). Glucose levels should be strictly monitored because of the difficulty of use. Exenatide is costly and inconvenient. It is still believed not to have proven benefits over other drugs used to treat diabetes, such as insulin (Ezzo and Ambizas).
The other off-label drug used in the treatment of Type-2 diabetes is Januvia, a product of Merck & Co., Inc. (Business Editors 2007). It was the first and only depeptidyl peptidase-4 inhibitor or DPP-4 to be accepted and used by the European Commission. It is said to enhance the body's ability to reduce blood sugar levels when it goes higher than normal. In treating Type 2 diabetes, Januvia improves glycemic control when combined with metformin. This is the recourse when diet, exercise and metformin have not effected sufficient glycemic control. Patients with Type-2 diabetes and using a PPAR gamma agonist may find it useful. All 27 countries of the EU have adopted its use. The drug was to be launched in the 42 EU countries, including Mexico, the U.S. And the Philippines (Business Editors).
The U.S. FDA approved Januvia in October 2006 as a monotherapy as well as an adjunct therapy to metformin or thiazolidinediones or TZDs (Business Editors 2007). These are intended to improve blood sugar control in Type-2 patients when diet and exercise alone would not work. The recommended dose is 100 mg once a day. It should not be used for Type-1 diabetes or diabetic ketoacidosis because it would not be effective in these cases. Common side effects were stuffy or runny nose and sore throat, upper respiratory infection and headache. The common and adverse gastrointestinal reactions include abdominal pain, nausea and diarrhea. Januvia is an oral and selective DPP04 inhibitor, which is taken once a day. It enhances the body's process of lowering blood sugar. It belongs to the incretin class of drugs. When the blood sugar level goes up, an incretin either helps the body regulate the high levels by stimulating the pancreas to increase the release of insulin. At the same time, it stimulates the liver to reduce the volume of glucose it produces. DPP-4 inhibitors promoted the body's natural ability to control blood sugar levels by activating these hormones. The drug has been approved in at least one country in the major regions of the world. These include Asia Pacific, Europe, the United States and Latin America. The recommended dose is also 100 mg per day with or without food. Patients with Type-2 diabetes who responded to clinical studies showed significant improvements in their hemoglobin A1C, fasting plasma glucose and the two-hour post prandial glucose (Business Editors).
A study was presented to the American Diabetic Association, which found that Januvia, in combination with metformin, significantly improved glycemic control (Business Editors 2007). It was also well-tolerated for 54 weeks by patients with Type-2 diabetes. Additional data also showed that Januvia also performed at high levels when added to a sulfonylurea, glimepiride or when added to a combination of sulfonylurea and metformin. There are no contraindications to Januvia. It is a component of Janumet, the first and only synthetic tablet. It puts a DPP-4 inhibitor and metformin for the treatment of Type-2 diabetes. It may also be used as an adjunct to diet and exercise. Janumet is contraindicated to renal disease, renal dysfunction, abnormal creatinine clearance, and acute or chronic metabolic acidosis. Like Byetta, it should not be used for Type-1 diabetes. An investigational study revealed that Januvia substantially improved blood sugar control when added to sulfonylurea or a combination of sylfonylurea and metformin as against sulfonylurea or sulfonylurea and metformin alone. It is generally well-tolerated as monotherapy, as an initial combination therapy or as an additional therapy. It should be given twice daily with meals at 100 mg. Merck $ Co. continues to experiment on…