What is Byetta?
Byetta is a solution for injection that contains the active substance exenatide. It is available in pre-filled pens ready for use with 5 or 10 micrograms of exenatide per dose.
What is Byetta used for?
Byetta is indicated for the treatment of type 2 diabetes in combination with other antidiabetic medicines (metformin and / or sulphonylurea) in patients whose blood glucose (sugar) levels are not adequately controlled with the maximum tolerated dose of these other medicines. Type 2 diabetes is also known as non-insulin-dependent diabetes.
The medicine can only be obtained with a prescription.
How is Byetta used?
Byetta should be administered by subcutaneous injection into the thigh, abdomen or upper arm using the pre-filled pen for solution for injection. The package contains a guide for the user.
Treatment with Byetta should be started with a dose of 5 micrograms twice a day for at least a month; subsequently it can be increased to 10 micrograms twice a day. Doses above 10 micrograms twice a day are not recommended. The first dose should be administered in the hour before the morning meal, the second in the hour before the evening meal. Byetta should never be given after meals. Special care is needed when Byetta is added to a sulphonylurea therapy, as there is a risk of hypoglycemia (low blood sugar levels). This risk is not expected when Byetta is added to metformin therapy. Byetta is not recommended for patients with severe renal impairment.
Patients being treated with Byetta should continue to follow their diet and exercise regimen. The safety and efficacy of Byetta have not been established in patients under the age of 18 years.
How does Byetta work?
Type 2 diabetes is a disease in which the pancreas does not produce enough insulin to control the level of glucose in the blood or where the body is unable to use insulin efficiently. The active ingredient of Byetta, exenatide, is an "incretino-mimetic". This means that it acts in the same way as incretin, a hormone produced in the intestine, that is, it induces an increase in the quantity of insulin released by the pancreas in response to food intake, thus favoring the control of blood glucose levels.
How has Byetta been studied?
Before being studied in humans, the effects of Byetta were analyzed in experimental models.
Byetta has been the subject of five main studies involving almost 2, 400 patients. In three of these studies, Byetta was compared with a placebo (a dummy treatment), as an "addition" to metformin (336 patients), a sulphonylurea (377 patients) or to both medicines (733 patients).
The other two studies compared the addition of Byetta or the addition of an insulin to the existing treatment with metformin and sulfonylurea. In one study, Byetta was compared with insulin gl'argine in 456 patients, while in the other study, Byetta was compared with biphasic insulin in 483 patients.
In all the studies, the main measure of effectiveness was the change in blood levels of a substance called glycosylated hemoglobin (HbA1c). The levels of HbA1c give an indication of the degree of glucose control in the blood.
What benefits has Byetta shown during the studies?
Byetta was more effective than placebo in reducing HbA1 levels, when used in combination with other antidiabetic drugs. After 30 weeks, the dose of 5 micrograms twice a day resulted in a reduction in HbA1c levels from 0.46 to 0.66% and the dose of 10 micrograms twice a day reduced these levels from 0.86 to 0, 91%. The use of placebo produced little or no benefits.
Byetta was as effective as the injected insulin. The dose of 10 micrograms twice a day by Byetta determined the reduction of the HbA1c level by 1.13%, compared to 1.10% recorded with the use of insulin gl'argine after six months. In the final study, the dose of 10 micrograms twice a day by Byetta reduced the HbA1c level by 1.01% after one year, compared to 0.86% recorded with biphasic insulin.
What are the risks associated with Byetta?
In clinical studies, the most common side effects with Byetta (seen in more than 1 patient in 10) were hypoglycemia (when it was given with a sulphonylurea), nausea, vomiting and diarrhea. For the full list of all side effects reported with Byetta, see the Package Leaflet.
Byetta should not be used in people who may be hypersensitive (allergic) to exenatide or any of the other substances.
Why has Byetta been approved?
The Committee for Medicinal Products for Human Use (CHMP) decided that Byetta's benefits are greater than its risks for the treatment of type 2 diabetes mellitus in combination with metformin and / or sulphonylurea in patients who have not achieved adequate glycemic control with the maximum tolerated dose of these drugs. The Committee recommended that Byetta be given marketing authorization.
Other information on Byetta:
On November 20, 2006, the European Commission issued a marketing authorization for Byetta, valid throughout the European Union, to Eli Lilly Nederland BV.
For the full EPAR version of Byetta, click here.
Last update of this summary: 12-2008.
