The U.S. Food and Drug Administration will investigate the possible association between treatment with the type 2 diabetes drug saxagliptin and an increased rate of hospitalizations for heart failure using data collected by the drug’s manufacturer during clinical trials. The agency released a "safety announcement" on Feb.11 that it had requested these data from Bristol-Myers Squibb and AstraZeneca, the two companies that together market saxagliptin as Onglyza and Kombiglyze XR.
The agency based its request on results reported last year in the SAVOR (Saxagliptin Assessment of Vascular Outcomes Recorded in Patients With Diabetes Mellitus)–TIMI 53 (Thrombolysis in Myocardial Infarction) trial, a trial with more than 16,000 patients with type 2 diabetes designed to test the cardiovascular safety of saxagliptin (N. Engl. J. Med. 2013;369:1317-26).
Although treatment with the drug produced no excess in the rate of the primary endpoint of all cardiovascular events, compared with a control group, the results showed a statistically significant, 0.7% absolute increase in the rate of hospitalizations for heart failure in the saxagliptin-treated patients, compared with those not on the drug, a 27% relative increase.
While presenting more detailed data on the heart failure hospitalization effect in a poster during the American Heart Association’s Scientific Sessions last November, Dr. Benjamin M. Scirica, lead author for the study, called the effect by saxagliptin on raising heart failure hospitalizations "real."
"Every drug has adverse effects. With these data, the calculation about saxagliptin can be made to a much more certain level. Clinicians need to weigh a patient’s risk factors, which drugs they can or cannot take, and a drug’s overall safety for ischemic events," said Dr. Scirica while presenting his poster last November. "At this point, we have no definitive data to a priori say don’t give saxagliptin to patients with heart failure."
The manufacturers are expected to submit the saxagliptin-trial data to the FDA by March 2014, after which the agency said it will "conduct a thorough analysis and report our findings publically."
The FDA’s statement added this caution to patients and physicians about its action:
"At this time, we consider information from the New England Journal of Medicine study to be preliminary. Our analysis of the saxagliptin clinical trial data is part of a broader evaluation of all type 2 diabetes drug therapies and cardiovascular risk. Patients should not stop taking saxagliptin and should speak with their health care professionals about any questions or concerns. Health care professionals should continue to follow the prescribing recommendations in the drug labels." The FDA also urged health care professionals and patients to report side effects involving saxagliptin products to the FDA MedWatch program.
Dr. Scirica said that he had been a consultant to Bristol-Myers Squibb and to several other drug companies and that he has received research grants from Bristol-Myers Squibb and AstraZeneca and from several other companies.
On Twitter @mitchelzoler