Sanofi announced new results of a large-scale epidemiological programme, conducted by independent researchers in the northern European countries, at Kaiser Permanente in Northern and Southern California, and at the University of North Carolina in the United States, providing further evidence that there was no increased risk of cancer in people with diabetes treated with Lantus (insulin glargine [rDNA origin] injection), compared to those treated with other insulins. These data were presented at the American Diabetes Association 72nd Scientific Sessions.

Aiming to evaluate cancer risk in diabetes and generate comprehensive insulin glargine exposure data from large databases, the epidemiological programme sponsored by Sanofi is the largest observational programme designed for this purpose to date.

These new results reinforce the established safety profile of Lantus, complementing the existing wealth of data already available resulting from more than 80,000 patients enrolled in clinical trials and over 47 million patient-years of treatment exposure to insulin glargine.

“Sanofi welcomes the results of the Northern European and United States epidemiological studies further supporting the safety of Lantus,” said Jean-Pierre Lehner, senior vice president, chief medical officer, Sanofi. “These findings reassure healthcare professionals, people living with diabetes and their caregivers of the safety profile of Lantus.”

This study is the largest of its kind with 447,821 patients using insulin and over 1.5 million personyears of observation. The average follow-up time is 3.1 years for patients on glargine and 3.5 years for those on other insulins. In answering the primary hypothesis, among all users of insulin, and similarly among users of human insulin, this observational study found no evidence of an increased risk of breast cancer in women (HR: 1.12; 95% CI: 0.99-1.27), prostate cancer in men (HR: 1.11; 95% CI: 1.00-1.24) and colorectal cancer in men and women (HR: 0.86, 95% CI: 0.76-0.98) in users of insulin glargine vs. other insulins.

Furthermore, there was no evidence of an increased risk in users of insulin glargine vs. other insulins relative to the pre-specified secondary hypothesis (risk of all forms of cancer combined) and the exploratory hypothesis (risk of lung or pancreatic cancer).

In conclusion, the results showed no increased risk for cancer in association with the use of insulin glargine compared to users of other insulins.

Lead investigator Peter Boyle, PhD, President of the International Prevention Research Institute (iPRI), Lyon, France, stated: “These findings provide further evidence that insulin glargine does not increase the risk of cancer. The results of this study are reassuring from a patient and physician perspective.”

The Northern European Study was carried out in five countries: Denmark, Finland, Norway, Sweden and Scotland. The Committee for Medicinal Products for Human Use (CHMP) in Europe expressed that the Northern European study results add important knowledge for understanding on the safety of Lantus.

The main analyses of this U.S. database study (using the Northern and Southern California Kaiser Permanente diabetes registries included 115,000 patients with median duration of 1.2 years for glargine use and 1.4 years for neutral protamine Hagedorn (NPH) among all insulin users (Lantus and NPH insulin) showed no association between use of insulin glargine and increased risk of breast cancer (HR: 1.0; 95% CI: 0.9-1.3), prostate cancer (HR: 0.7; 95% CI: 0.6-0.9) or colorectal cancer (HR: 1.0; 95% CI: 0.8-1.2) (primary endpoints). Furthermore, there was no association between Lantus use and increased risk of all cancers combined (HR: 0.9; 95% CI: 0.9-1.0) (secondary endpoint).

In a sub-analysis using one specific methodology (counting of dose), there was a suggestion of a very modest increase of breast cancer in patients with two or more years of Lantus® use. When another methodology was adopted (counting of prescriptions), no such suggestion existed. Principal Investigator Laurel Habel, PhD, Research Scientist at the Kaiser Permanente Northern California Division of Research, noted that results of their study should be viewed cautiously, given the relatively short duration of glargine use, the low number of events, and the large number of associations examined.

The Northern European Database Study and the US study using the Northern and Southern California Kaiser Permanente diabetes registries were endorsed by the European Medicines Agency (EMA).

The US database study was complemented by findings from researchers at the University of North Carolina, using the healthcare database MedAssurant (43,306 patients on glargine and 9,147 on NPH; mean duration of treatment: 1.2 years for glargine group and 1.1 years for NPH group). There was no evidence of an increased risk for cancer, and specifically for breast cancer.

“This robust analysis of high quality data from the US shows that there is no association with an increased risk of cancer in users of insulin glargine,” concluded John Buse, MD, PhD, former president of the American Diabetes Association, and Director of the Diabetes Care Center at the University of North Carolina, USA, who led the U.S. database studies.

As with the results of the Northern European Study, data from the US Kaiser Permanente and MedAssurant studies showed no association between use of Lantus and increased risk of the cancers evaluated among all insulin users tested. Additional results are expected from a third observational study, the International Study of Insulin and Cancer (ISICA), which will be completed in 2012.