Boehringer Ingelheim Pharmaceuticals, Inc. and Eli Lilly and Company announced the clinical trial enrollment of patients for CAROLINA (Cardiovascular Outcome Study of Linagliptin versus Glimepiride in patients with type 2 diabetes) has been completed. Linagliptin is currently the only DPP-4 inhibitor that is being compared to a sulfonylurea in a long-term cardiovascular (CV) outcome study.

Linagliptin, marketed in the US as Tradjenta, is a once-daily tablet used along with diet and exercise to improve glycemic control in adults with type 2 diabetes. Tradjenta should not be used in patients with type 1 diabetes or for the treatment of diabetic ketoacidosis (increased ketones in the blood or urine).

The study includes over 6,000 patients in 43 countries at more than 600 sites around the world. The aim of the study is to investigate and compare the long-term impact on CV morbidity and mortality of treatment with Tradjenta or glimepiride over a period of about 6 - 7 years.  Additionally, the study will compare secondary measures of efficacy with regard to lowering blood glucose as well as safety parameters, including body weight and the incidence of hypoglycemia in patients with type 2 diabetes at elevated cardiovascular risk receiving usual care, and compare the outcome against glimepiride.

"CAROLINA will evaluate the cardiovascular safety of linagliptin compared to the sulfonylurea glimepiride," said Dr Julio Rosenstock, director of the Dallas Diabetes and Endocrine Center at Medical City in Dallas and Principal Investigator of the study. "Sulfonylureas are frequently used add-on therapy to metformin, which is considered the standard first-line therapy. This is the first time a DPP-4 inhibitor is being directly compared to a sulfonylurea in a long-term cardiovascular outcome study."

The primary endpoint of CAROLINA will be timed to the first occurrence of either CV death, non-fatal myocardial infarction, non-fatal stroke or hospitalization for unstable angina pectoris.  The study is expected to complete in 2018.

"There are limited available data reporting on CV-related comorbidities with current therapies for patients with type 2 diabetes. For the first time, this study has the potential to compare the CV morbidity, mortality and safety of the DPP-4 inhibitor linagliptin to the commonly prescribed sulfonylurea glimepiride," said Christophe Arbet-Engels, vice president, metabolic-clinical development and medical affairs, Boehringer Ingelheim. "It is our hope CAROLINA will help us to better understand the effect on cardiovascular outcomes of linagliptin compared to glimepiride, and, therefore, add to the knowledge base  physicians use to decide how to treat their patients."

CAROLINA evaluates the CV safety of linagliptin in comparison to glimepiride in patients with T2D and at increased CV risk.

In January 2011, Boehringer Ingelheim and Eli Lilly and Company announced an alliance in the field of diabetes that centres on four pipeline compounds representing several of the largest treatment classes. This alliance leverages the companies' strengths as two of the world's leading pharmaceutical companies, combining Boehringer Ingelheim's solid track record of research-driven innovation and Lilly's innovative research, experience, and pioneering history in diabetes. By joining forces, the companies demonstrate commitment in the care of patients with diabetes and stand together to focus on patient needs.