Approved by the US Food and Drug Administration (FDA) in 2009, saxagliptin (brand name Onglyza) is prescribed, along with diet and exercise, to lower blood sugar (glucose) levels in patients with type 2 diabetes by stimulating the pancreas to make more insulin. Insulin helps the body's cells convert glucose into energy.
A new large investigation of diabetes patients found that this medication did not increase or decrease heart attack risk but may cause issues for heart failure patients who had a greater likelihood of hospitalization if they were taking saxagliptin.
"Ask your pharmacist about new diabetes medications."
Deepak Bhatt, MD, senior physician and professor from the VA Boston Healthcare System and the TIMI (Thrombolysis In Myocardial Infarction) Study Group, Cardiovascular Division, Brigham and Women’s Hospital and Harvard Medical School, and his collaborators conducted this study of 16,492 patients with type 2 diabetes and risk factors for heart disease.
These participants randomly received either 5 milligrams of saxagliptin daily (or 2.5 milligrams daily in patients with kidney impairment) or a matching dose of placebo (fake medication).
If needed, the patients' doctors had the option to provide additional treatment with other diabetes and cardiovascular medications.
After an average follow-up of about two years, the researchers found that patients taking saxagliptin were at no greater risk of having a heart attack than those in the placebo group.
The authors reported that the combined number of cardiovascular deaths, non-fatal heart attacks or non-fatal ischemic strokes was similar in both groups — 7.3 percent in saxagliptin group compared to 7.2 percent in the placebo group.
“We are reassured by the lack of any increase in the risk for heart attack among patients receiving this drug,” said Benjamin Scirica, MD, with the TIMI Study Group, Cardiovascular Division, Brigham and Women’s Hospital and Harvard Medical School, in a press release.
Co-principal investigator Itamar Raz, MD, at the Hadassah Medical Center in Israel added in the same release, “Patients who received saxagliptin also had better control of blood sugar levels and a reduced need for insulin therapy. Saxagliptin also prevented progression of microalbuminuria.”
Common among diabetes patients, microalbuminuria is a condition when the kidneys leak protein into the urine and is a sign of kidney damage.
The researchers also observed that patients taking saxagliptin were more likely to achieve an average blood sugar level that is considered normal (measured as a glycated hemoglobin level that is less than 7 percent) at the end of treatment.
An increased number of patients in this study, however, also reported at least one hypoglycemic event (a low blood sugar level) in the treatment group when compared with placebo (15.3 versus 13.4 percent).
The most common side effects observed with Onglyza (saxagliptin) are upper respiratory tract infection, urinary tract infection and headache. Other side effects include allergic-like skin reactions such as rash and hives.
In a statement, study chairman Eugene Braunwald, MD, of the TIMI Study Group, Cardiovascular Division, Brigham and Women’s Hospital and Harvard Medical School, warned, “Our data also show an increase in hospitalization for heart failure in patients who received saxagliptin, which was not expected and deserves further study.”
Dr. Bhatt hopes that these findings will help to guide physicians and improve their ability to prescribe different diabetes medications in a more evidence-based and data-driven way.
“Few diabetes drugs have been studied as thoroughly as saxagliptin, and this outcome trial raises the bar for evaluating the safety of all diabetes drugs,” said Dr. Bhatt.
This study was published September 2 in The New England Journal of Medicine and presented at the European Society Cardiology 2013 Congress in Amsterdam. The research was funded by the drug's makers, AstraZeneca and Bristol-Myers Squibb.