What’s the Problem?
Studies have found that side effects of the type 2 diabetes drug Januvia may increase the risk of damage to the pancreas and chronic pancreatitis, which may ultimately lead to the development of pancreatic cancer.
What is Janumet?
Janumet (generic: sitagliptin and metformin) is known as dipeptidyl peptidase-4 (DPP-4) inhibitor, and belongs to a broader class of diabetes medications called incretin mimetics. The combination of sitagliptin and metformin is designed to help control blood sugar levels both directly after meals and between meals. Janumet is manufactured by Merck & Co., and was approved by the U.S. Food & Drug Administration (FDA) in April 2007.
Janumet and Pancreatitis
In September 2009, FDA announced that it was updating the prescribing information for Janumet and Januvia (generic: sitagliptin), another incretin mimetic diabetes drug, to include information on reported cases of acute pancreatitis in patients treated with the medications. The announcement followed FDA’s review of at least 88 post-marketing reports of acute pancreatitis — including two cases of hemorrhagic or necrotizing pancreatitis — in patients who took sitagliptin from Oct. 16, 2006 to Feb. 9, 2009.
The agency issued a Drug Safety Communication in March 2013 which stated that it was reviewing new studies which had identified an increased risk for pre-cancerous cell changes and pancreatitis associated with incretin mimetic diabetes drugs. According to the FDA, the findings were “based on examination of a small number of pancreatic tissue specimens taken from patients after they died from unspecified causes.”
Signs and symptoms of acute pancreatitis may include:
- Upper abdominal pain
- Abdominal pain that radiates to your back
- Abdominal pain that feels worse after eating
- Rapid pulse
- Tenderness when touching the abdomen
Chronic pancreatitis symptoms include:
- Upper abdominal pain
- Losing weight without trying
- Oily, smelly stools (steatorrhea)
Janumet and Pancreatic Cancer
Patients treated with sitagliptin (one of the main active ingredients in Janumet) have more than a doubled risk of developing pancreatic cancer, according to a July 2011 study published in the journal Gastroenterology. Lead researcher Dr. Peter Butler said it can be difficult to know the extent of damage done to the pancreas without removing it and examining it. As a result, many cases of pancreatic cancer are not diagnosed until the disease has progressed to an advanced stage.
In a 2015 review of medical literature, researchers summarized the results of FDA adverse event reports. They found a high incidence of pancreatic cancer in patients treated with DPP-4 inhibitor diabetes drugs, and concluded that further studies were needed to investigate this risk.
Pancreatic Cancer Treatment and Prognosis
Depending on the type and stage of pancreatic cancer, treatment options may include:
- Ablation or embolization treatments
- Radiation therapy
- Chemotherapy and other drugs
Each year about 45,000 people in the U.S. are diagnosed with pancreatic cancer. The prognosis (long-term outlook) is poor, with most patients dying within one year of their diagnosis. In the U.S., pancreatic cancer is the 9th or 10th most commonly diagnosed cancer, but the fourth leading cause of cancer death in men and women.
Janumet Thyroid Cancer
The Gastroenterology study noted above also found a minor increase in thyroid cancer, with only 2 cases reported out of the cohort. The 2015 analysis of FDA adverse event reports found an increase in thyroid cancer in patients treated with incretin mimetics, although glucagonlike peptide-1 (GLP-1) receptor agonists like Victoza (generic: liraglutide) had a much higher incidence of the disease.
Thyroid Cancer Symptoms
- Lump or swelling in the neck (most common)
- Pain in the neck and/or ears
- Trouble swallowing
- Trouble breathing / constant wheezing
- Hoarse voice
- Frequent cough not related to a cold.
FDA warned in August 2015 that Janumet and other DPP-4 inhibitors may cause severe, debilitating joint pain. The agency received at least 28 reports of joint pain in patients treated with sitagliptin from 2006 to 2013. Some patients had to be hospitalized because symptoms were so severe. As a result of these problems, FDA required that a joint pain warning be added to the labeling of the medications.
Janumet Side Effects
- Acute Pancreatitis
- Hemorrhagic Pancreatitis
- Necrotizing Pancreatitis
- Pancreatic Cancer
- Thyroid Cancer
- Heart Failure
- Gallbladder Disease
- Bile Duct Disease
- Joint Pain
Jul 2006 – New Drug Approval acceptance announced
July 31, 2006 – Merck announces acceptance of New Drug Approval (NDA) for MK-0431A
Dec 2006 – Merck chooses Janumet
December 1, 2006 – Merck chooses Janumet as the trademark for its type 2 diabetes combination of sitagliptin and metformin.
Apr 2007 – FDA approval
April 2, 2007 – Janumet approved by the FDA.
Sep 2009 – Prescribing information updated
September 25, 2009 – Prescribing information for Janumet and Januvia updated to include information on reported cases of pancreatitis associated with the drugs.
Jul 2011 – Gastroenterology study published
July 2011 – Study published in Gastroenterology finds that patients who took sitagliptin (one of the main active ingredients in Janumet) were twice as likely to get pancreatic cancer compared to people who took other types of diabetes drugs.
Feb 2012 – FDA approval
February 2, 2012 – FDA approves Janumet XR (sitagliptin and metformin HCl extended-release).
Mar 2013 – FDA announces investigation
March 14, 2013 – FDA announces that it is investigating new studies which suggest an increased risk of pancreatitis with incretin mimetic diabetes drugs.
Aug 2015 – Janumet labels updated
August 28, 2015 – Janumet labels updated to include a warning about severe, debilitating joint pain.