Byetta is a drug administered via injection twice daily—within an hour prior to breakfast and dinner. Byetta (exenatide) is intended to treat Type 2 diabetes, mimicking the effects of incretins which are hormones produced and released by the intestines when a person eats a meal. The human-glucagon-like peptide-1 (GLP-1) increases insulin secretions from the pancreas, slows the absorption of glucose in the stomach and effectively slows the speed of the glucagon. Exenatide is a synthesized version of a substance found in the saliva of the Southwestern Gila monster and is 50% identical to a hormone found naturally in the human body. GLP-1 has been found to reduce the appetite by slowing the rate at which food leaves the stomach—although patients are cautioned against using Byetta as a treatment for obesity.
When the pancreas is producing GLP-1, digestive enzymes may also be manufactured. If these digestive enzymes are activated before they can leave the pancreas, they may end up digesting pieces of tissue in the pancreas which can lead to inflammation, abdominal pain, fever and nausea. Amylin Pharmaceuticals and Eli Lilly originally worked jointly to manufacture Byetta. Later, in 2011, the two companies split with Amylin gaining “custody” of Byetta. By 2012 Amylin ended up selling the company to Bristol-Meyer Squibb.
Byetta Thyroid Cancer Safety Issues
While Byetta gained FDA approval in 2005, Byetta problems soon began surfacing. Between 2005 and 2007, thirty patients taking Byetta experienced symptoms of pancreatitis. When Byetta was discontinued, the symptoms resolved in nearly every case. A study published in February in the JAMA Internal Medicine Journal found Byetta was responsible for at least twice the number of pancreatitis attacks—lesions found in the pancreas were believed to be the result of exenatide. Even though pancreatitis is more common among diabetics (3 in 1,000) those numbers jump to 6 in 1000 among those taking Byetta.
Further, several smaller studies have pointed to Byetta as a risk factor in the development of thyroid cancer as well. In fact, one study concluded that thyroid cancer was twice as likely among those taking Byetta. While thyroid cancer is not considered as difficult to treat as pancreatic cancer, it is nonetheless a serious disease. In 2008 six people were hospitalized with necrotizing pancreatitis—two of these patients died. Byetta was found to be the only common link between the six. Other deaths may also be related to Byetta, however due to those patients having additional health issues it is difficult to definitively tie them to Byetta. From 2005-2009, over seven million prescriptions were issued for Byetta, bringing millions of dollars to the manufacturers.
Byetta Side Effects
Aside from the serious issues of thyroid cancer, pancreatic cancer and pancreatitis, Byetta may cause some lesser—yet still serious—side effects. Relatively minor and common side effects are dizziness, diarrhea and nausea among those taking Byetta with nearly half of all those taking the drug suffering nausea. About five percent of those taking Byetta will suffer heartburn, decreased appetite, increased sweating and a feeling of weakness in the muscles. When Byetta is taken with other diabetic drugs, symptoms of low blood sugar may occur. Allergic reactions, while not common, can occur among Byetta users. The face, lips and throat may swell, even to the point where breathing becomes difficult. Any unexplained changes in the output of urine, undue swelling in the hands or feet or a dull ache in the mid or lower back should be a sign to seek medical attention as pancreatitis may be indicated.