Byetta and Bydureon are two brand name drugs used to treat type 2 diabetes in adults. They are both injectable forms of a generic drug called exenatide and are designed to be used along with diet and exercise to control blood sugar levels. Byetta was first approved in 2005 and Bydureon in 2012. The only difference between the two medications is that Bydureon is a long-lasting form that only needs to be used once a week. Byetta is used twice a day.

Both of these medications have been useful in regulating blood sugar for people with type 2 diabetes, but there are some serious possible side effects too. These include kidney failure, pancreatitis, and even certain types of cancer. This latter risk led to the U.S. Food and Drug Administration (FDA) requiring a black box warning on Bydureon.

Uses for Byetta and Bydureon

Byetta, injectable exenatide, was created and tested by Amylin Pharmaceuticals in conjunction with Eli Lilly. The FDA approved Byetta in 2005 for the treatment of type 2 diabetes in adults. It is supposed to be used twice a day along with changes in diet and exercise to control blood sugar levels. It is not supposed to be used in people with type 1 diabetes or diabetic ketoacidosis.

The FDA approved Bydureon, also injectable exenatide, in 2012. Amylin Pharmaceuticals, along with these two medications, were bought by Bristol Myers Squibb, also in 2012. The company also has a partnership with AstraZeneca to develop diabetes medications, including Byetta and Bydureon.

Bydureon contains the same medication as Byetta, but in a long-lasting format so that it only needs to be injected once a week. It is the first such medication for treating type 2 diabetes and was an important step forward in the development of diabetes drugs.

Although these medications have only been approved for treating type 2 diabetes along with exercise and dietary changes some doctors may prescribe them for weight loss. A common, and usually not unwanted side effect, is weight loss. The pharmaceutical companies have even marketed these drugs as having weight loss as a positive benefit, as many patients with diabetes need to lose weight for health reasons.

How Byetta and Bydureon Work

Exenatide belongs to a class of drugs that are called incretin mimetics. They act to stimulate the production of insulin. Insulin is a hormone produced in the pancreas that regulates blood sugar. When blood sugar levels are high, the pancreas should make more insulin. In people with type 2 diabetes, either the pancreas has stopped making as much insulin as it should or the body has become less sensitive to insulin.

Incretin mimetics stimulate the pancreas, causing it to produce more insulin, which in turn lowers blood sugar levels. Managing diabetes by regulating blood sugar is important. Chronically high blood sugar can cause many serious complications from stroke and heart disease to kidney failure and vision loss. Type 2 diabetes can also be managed by losing weight, eating a better diet, exercising, and quitting smoking, but some patients need the boost that drugs like Byetta and Bydureon give to insulin in addition to these lifestyle changes.

Incretin mimetics like exenatide work by mimicking a natural hormone that stimulates insulin. This natural hormone is called glucagonlike peptide-1, or GLP-1. Exenatide is a synthetic, or laboratory-made, version of a hormone that was first found in the saliva of the Gila monster. It is similar enough to GLP-1 to be able to stimulate insulin production and suppress the secretion of other hormones that increase blood sugar.

This hormone also has the effect of slowing the rate at which food leaves the stomach for the intestines. This helps regulate blood sugar by slowing down the rate of glucose going into the bloodstream. It also has the side effect of making the person taking the medication feel fuller faster when eating. It is this effect that is thought to lead to weight loss as a side effect.

Side Effects

Byetta and Bydureon may both cause several side effects in patients taking it. The most common of these are not severe. Nausea is the most-often reported side effect, although most patients find that the feeling lessens over time. Other common side effects include acid stomach, diarrhea or vomiting, constipation, weakness and dizziness, a jittery feeling, and headaches. Weight loss is also common, but not usually considered a negative side effect.

There are other possible side effects, and any of these that are severe or that do not get better with time should be reported to a doctor. It is also possible for certain patients to be allergic to these medications. Signs of an allergic reaction include a rash, itchiness, swelling, and difficulty breathing. This may require emergency medical treatment. Some patients taking Bydureon have also experienced skin reactions at the site of the injection. Severe reactions may include swelling, pain, blisters, or an open wound, and may require surgery to treat.

Pancreatitis and Pancreatic Cancer

In 2007 the FDA issued a warning about Byetta that it may increase the risk of pancreatitis and pancreatic cancer in patients. Since then, more research has been conducted showing a connection between the medication and these serious conditions. The FDA required the drug companies conduct more studies, and updated its warning about the possible link in 2013.

Current labeling indicates that Byetta and Bydureon may cause inflammation of the pancreas as a side effect. Pancreatitis is a serious medical condition that can cause complications like infections, diabetes, breathing problems, kidney failure, malnutrition, and pancreatic cancer. If untreated, pancreatitis can lead to death. The research is mounting that exenatide medications can cause pancreatitis and subsequent pancreatic cancer and the FDA is currently reviewing that research.

The FDA currently recommends that patients with a history of pancreatic problems should not take these medications. They also suggest that patients watch out for signs of pancreatitis, which can include severe upper abdominal pain, pain that feels worse after eating, tenderness when that area of the abdomen is touched, vomiting, and nausea

Thyroid Cancer

Another serious risk has emerged in the research since the discovery of the possible risk of pancreatitis and pancreatic cancer. Patients taking exenatides may also be at a greater risk for developing thyroid cancer. The thyroid is a gland in the throat that produces hormones responsible for regulating metabolism.

Some studies have found that exenatides increase the risk of developing thyroid cancer in lab rats, but the connection in humans has not been proven. Other studies have concluded that the risk of developing cancer is outweighed by the benefits of these medications.

Currently, the label for Bydureon does warn that it may cause thyroid tumors and cancer. Patients are warned not to take the medication if they have a personal or family history of thyroid cancer or other thyroid conditions. The FDA also warns that all patients should look for signs of a thyroid tumor, including hoarseness, difficulty swallowing, shortness of breath, and a lump in the neck.

Lawsuits

Because of the possible risk of developing such serious conditions as pancreatitis, pancreatic cancer, and thyroid cancer while taking Byetta or Bydureon, and because those risks were not communicated at the time the medications came on the market, several lawsuits have been filed against Bristol Myers Squibb and Eli Lilly. Complainants claim that the companies failed to warn the public about the risks and that the actively concealed information about these side effects.

There have been many reports of people dying while taking Byetta or Bydureon, most often from pancreatitis or pancreatic cancer, and the families of these victims are filing lawsuits. If you lost a loved one who was being treated with these medications or you or someone you care about is struggling with difficult side effects, you may be eligible for a lawsuit against the companies that manufacture and market these drugs.