Byetta is a drug marketed for the treatment of Type 2 diabetes. While some diabetes drugs come in pill form, Byetta is a pre-filled pen which the patient injects one hour prior to the morning and evening meal. Unlike some other diabetic drugs, Byetta (exenatide) is made from a synthetic form of a hormone—exendin 4—which naturally occurs in the saliva of the Southwestern Gila monster and was discovered in 1992. The synthesized version of the hormone is nearly 50% identical to another hormone which occurs naturally in the human digestive tract—GLP-1. This GLP-1 hormone increases the insulin in the body, enabling it to balance excessively high levels of blood sugar. The body of a diabetic may lose the ability to produce the necessary levels of GLP-1, allowing blood sugar levels to rise to potentially dangerous levels.
How Byetta Works
Exenatide’s synthetic hormone remains effective for longer periods of time, effectively stabilizing blood sugar levels. Byetta has also been found to decrease the rate of the emptying of the stomach. This can lead to a decrease in appetite and, consequently, a reduction in weight. Byetta was approved by the FDA in 2005, and, like several other new diabetic drugs released around the same time, generated significant revenues for its manufacturer, Amylin. Between April, 2005 and October, 2008, Byetta was prescribed over seven million times, and by 2008 the drug had earned Amylin over $700 million dollars.
Byetta FDA Warnings
Controversy was not far behind, however. While no black box warning has been issued for the drug, Byetta FDA warnings were given beginning in 2007 following reports of adverse health effects from patients taking Byetta. Even though Byetta has actually been associated with several fatalities there remain few who advocate for a complete recall of the drug. Byetta appears to cause an increase in thyroid cancer as well as a potential increase in the risk of pancreatitis and pancreatic cancer. Overstimulation of the pancreas may lead to pancreatic problems and a study published in Gastroenterology by Dr. Peter Butler presents a link between Byetta users and the development of thyroid cancer.
Byetta Safety Concerns
The official newspaper of the American Gastroenterology Association believes the risk of Byetta thyroid cancer among users is significantly higher than those with the same risk factors who do not use Byetta. Butler noted that “appropriate prospective studies” are required to rule out increased risks of thyroid cancer, pancreatitis and pancreatic cancer. Among thirty adverse reports presented to the FDA, six of those patients experienced substantial increases in Byetta pancreatitis symptoms when the doses were doubled and over two-thirds of the thirty patients showed significant improvement once Byetta was discontinued.
Taking several credible studies into consideration it appears that overall Byetta users have three times the risk of developing pancreatic cancer and six times the risk of developing acute pancreatitis than those taking other diabetic drugs. In a recent report released in April, 2013, the Institute for Safe Medication Practices published findings which showed Byetta was responsible for two times the rate of thyroid tumors and thyroid cancer when compared to some other diabetic medications. While thyroid cancer is generally considered treatable, it remains a serious condition.