FDA statement on Byetta
Just days after approving Byetta as a monotherapy
and making changes to the label for Byetta, the FDA issued the following
Food and Drug Administration today acted on new safety information about
possible kidney function problems, including kidney failure, in patients taking
Byetta (exenatide), a drug used to treat Type 2 diabetes.
2005 through October 2008, the FDA received 78 reports of problems with kidney
function in patients using Byetta. Some cases occurred in patients with
pre-existing kidney disease or in patients with one or more risk factors for
developing kidney problems.
Nearly 7 million prescriptions for Byetta were
dispensed between April 2005 and September 2008. The 78 cases represent a small
percentage of the total number of patients using the drug to control blood
sugar (glucose) levels.
common side effects associated with Byetta include nausea, vomiting, and
diarrhea. These side effects may have contributed to the development of altered
kidney function. Kidney malfunction can result in a build-up of waste products
in the blood, leading to serious illness or life-threatening conditions.
professionals and patients taking Byetta should pay close attention to any
signs or symptoms of kidney problems,” said Amy Egan, M.D. M.P.H., of the
Division of Metabolism and Endocrinology Products at the FDA’s Center for Drug
Evaluation and Research. “Patients also should be aware that problems with
kidney function could lead to changes in urine color, frequency of urination or
the amount of urine, unexplained swelling of the hands or feet, fatigue, changes
in appetite or digestion, or dull ache in mid to lower back.”
Note that Diabetic Investor added the
also be noted that according to the American Diabetes Association:
Diabetes is the leading cause of kidney failure, accounting for 44% of
new cases in 2005.
In 2005, 46,739 people with
diabetes began treatment for end-stage kidney disease in the
United States and Puerto Rico.
In 2005, a total of 178,689
people with end-stage kidney disease due to diabetes were living on chronic
dialysis or with a kidney transplant in the United States and Puerto Rico.
In a joint press release issued by Amylin (NASDAQ:AMLN) and Lilly
(NYSE:LLY) the companies noted that this issue was addressed in the updated
Byetta label. According to that press release;
“The FDA update issued today aligns with the BYETTA
label approved last week. The current label reflects our understanding of
post-marketing reports of renal events and provides physicians with updated
guidance about appropriate use in patients with renal conditions. There is no
evidence from preclinical and clinical studies that BYETTA has any direct toxic
effect on the kidney,” said Orville G. Kolterman, M.D., senior vice
president of research and development, Amylin Pharmaceuticals.
“Post-marketing reports of serious changes in renal function have been
rare and usually complicated by other factors that could have contributed to
the kidney problems. It is also important to note that diabetes is the leading
cause of kidney failure. Information about use of BYETTA in patients with
impaired renal function was included in the initial product label in 2005 and
was updated in 2007. We remain committed to working closely with the FDA to
ensure that physicians and patients are provided with accurate information
about any potential risks associated with the use of our products.”
As Diabetic Investor pointed out back when Amylin reported
earnings and again when Byetta was approved as a monotherapy, the updated label
language will apply to all GLP-1 products not juts Byetta. When Victoza® from
Novo Nordisk (NYSE:NVO) gains FDA approval Diabetic Investor expects the label
language to be similar if not identical to what’s included in the new Byetta
Diabetic Investor doubts today’s statement by the FDA will
have much impact on Byetta sales as the drugs side effect profile is well
established. If there is a positive to be found in the FDA’s statement is they
correctly note that the number of cases is a very small percentage of Byetta
Sooner or later people will just have to accept that no
drug, however well tested, can offset the many complications associated with diabetes.
Try as these drug companies do to minimize adverse events the fact remains that
poorly controlled diabetes leads to many serious complications. Until the day
comes when patients are diagnosed early in the diseases progression and treated
aggressively, these complications will continue.