Summary Safety Review - Incretin-Based Therapies - Assessing the Potential Risk of Pancreatic Cancer

Review decision

A Summary Safety Review complements other safety related information to help Canadians make informed decisions about their use of health products. Each summary outlines what was assessed in Health Canada’s review, what was found and what action was taken by Health Canada, if any.


Issued: 2016-10-21

Product

Incretin-based therapies: sitagliptin, saxagliptin, linagliptin, alogliptin (alone or in combination with metformin) and exenatide.

Potential Safety Issue

Pancreatic cancer

Key Messages

  • Incretin-based therapies are prescription drugs that are used with or without other anti-diabetic drugs along with diet and exercise to improve blood sugar levels in adult patients with type 2 diabetes.
  • This review was triggered by studies that suggested a potential link between the use of incretin-based therapies and an increased risk of pancreatic cancer.
  • Health Canada's safety review concluded that there is not enough evidence at this time to confirm this link. Health Canada will continue to monitor the safety of incretin-based therapies, and encourages healthcare professionals to report side effects that may be linked to the use of incretin-based therapies.

Overview

During the last few years, a small number of studies have found a possible link between the use of incretin-based therapies and an increased risk of pancreatic cancer. Worldwide, the number of case reports of pancreatic cancer potentially linked to the use of incretin-based therapies has been increasing steadily. This new evidence led Health Canada to assess the risk of pancreatic cancer linked to the use of incretin-based therapies. Pancreatic cancer is one of the deadliest forms of cancer with a low survival rate 5 years after diagnosis (6%). Risk factors for pancreatic cancer include smoking, obesity, a family history of pancreatic cancer, chronic pancreatitis and diabetes.

Use in Canada

  • Incretin-based therapies are prescription drugs that are used with diet and exercise, and with other drugs, to improve blood sugar levels in adults with type 2 diabetes. They work by improving the secretion of insulin by the pancreas by either increasing the level of incretins in the blood or by acting like incretins.
  • There are currently 9 pharmaceutical incretin-based therapies marketed in Canada. These products are either (1) DPP-4 inhibitors (sitagliptin, saxagliptin, linagliptin and alogliptin), used alone or in combination with metformin, or (2) incretin-like molecules (exenatide), approved only for use with other anti-diabetic agents.
  • Sitagliptin was the first incretin-based therapy sold in Canada starting in 2008 and alogliptin was the latest in 2014.
  • Incretin-based therapies are widely used in Canada, with close to 16 million prescriptions being filled in Canada since they have been marketed.

Safety Review Findings

  • At the time of the review, going back to the introduction of incretin-based therapies in Canada (2008), 15 cases of pancreatic cancer have been reported to Health Canada that may have been linked to the use of incretin-based therapies.
  • In February 2014, the United States Food and Drug Administration (U.S. FDA) and the European Medicines Agency (EMA) published a scientific article that concluded that a link between incretin-based therapies and pancreatitis/pancreatic cancer could not be made based on data at hand. Both groups continue to look into this safety issue.
  • Although some non-clinical studies using animal or human models have suggested that the use of incretin-based therapies may be linked to an increased risk of pancreatic cancer, results from clinical trials and many studies looking at the patterns, causes, and effects of health and disease conditions in people, do not support this link.
  • Lately, two studies12 concluded that incretin-based therapies were not linked to pancreatic cancer. A third study3 reported an increased risk of pancreatic cancer only for patients who had taken sitagliptin non-stop for close to 1 year. It is possible that this observation was due to patients that already had pancreatic cancer that has not been diagnosed before being treated with sitagliptin.

Conclusions and actions

  • Health Canada's review concluded that there is not enough evidence at this time to confirm a link between incretin-based therapies and pancreatic cancer.
  • Health Canada will continue to monitor safety information involving incretin-based therapies, as it does for all health products on the Canadian market, to identify and assess potential harms. Health Canada will take appropriate and timely action if and when any new health risks are identified.

Additional information

The analysis that contributed to this safety review included scientific and medical literature, Canadian and international adverse reaction reports and what is known about the use of this drug both in Canada and internationally.

For additional information, contact the Marketed Health Products Directorate.

References

  1. Azoulay L, Filion KB, Platt RW et al, (2016), Incretin-based drugs and the risk of pancreatic cancer: An international multi-centre cohort study, BMJ on-line publication. http://dx.doi.org/10.1136/bmj.i581
  2. Knapen LM, van Dalem J, Keulemans YC, et al, (2016), Use of incretin agents and risk of pancreatic cancer: A population-based cohort study, Diabetes, Obesity and Metabolism 18:258-265.
  3. Tseng C-H, (2016), Sitagliptin and pancreatic cancer risk in patients with type 2 diabetes, Eur J Clin Invest 46:70-79.