Four studies involving Sanofi SA's Lantus insulin appeared to blunt concerns that it might cause cancer.
Lantus is the top-selling insulin in the U.S. One major study looked at the use of Lantus by people in early stages of diabetes or with blood-sugar problems and found the product failed to cut the risk of heart attacks and strokes compared with standard treatment.
But the 12,500-patient clinical trial also found no significant increased risk of cardiovascular problems or cancer during a follow-up of more than six years. The study was published online Monday in the New England Journal of Medicine and presented, in addition to three other studies set up to look at Lantus and cancer risk, at the annual scientific meeting of the American Diabetes Association.
France-based Sanofi hopes the new research will put to rest safety concerns surrounding its top-selling product, which had sales of about $4.9 billion last year. Lantus is a long-acting form of artificial insulin—known as insulin glargine—that is injected once a day. Diabetes affects about 26 million Americans.
In 2009, studies suggested Lantus might be associated with an increase in cancer, possibly more so than other long-acting insulins. The U.S. Food and Drug Administration began a safety review of Lantus and last year said the 2009 data was "inconclusive."
Three of the new studies used insurance-claims or electronic medical-record databases to look at insulin use and breast cancer, prostate cancer and colon cancer, as well as overall cancer rates. The largest study, the Northern European Study of Insulin and Cancer, followed nearly 450,000 patients in Norway, Sweden, Denmark, Finland and Scotland for more than three years. "It showed absolutely no association at all," said Peter Boyle, the study's principal investigator and president of the International Prevention Research Institute, in France.
A study by Kaiser Permanente Northern California Division of Research looked at data from 115,000 people taking Lantus or another long-acting insulin. It compared new insulin users as well as patients who had switched to Lantus from another insulin. Overall, researchers found no increased cancer risk, except for a small increase of breast cancer among new insulin users. Laurel Habel, a Kaiser Permanente research scientist and the lead researcher, said the increase is likely a chance finding; a true increase in risk would show up in other patient groups.
A study, led by University of North Carolina researchers, looked at a MedAssurant database of more than 50,000 patients in Louisiana and Massachusetts and compared 43,000 people starting Lantus with patients who had started another insulin. The study followed the patients, all cancer-free at the start, for more than a year and found no higher cancer risk.
Dr. Habel said a limitation of the studies was the short follow-up. Cancer usually takes years to develop. Still, the studies' sheer size makes Lantus one of the most-studied insulins on the market, doctors say.
Dr. John Buse, director of the diabetes center at the University of North Carolina School of Medicine, said diabetes patients are already at higher risk of cancer. Older age and increased body weight are factors linked to the development of both Type 2 diabetes and cancer, he said.
Lantus is the top-selling insulin in the U.S. One major study looked at the use of Lantus by people in early stages of diabetes or with blood-sugar problems and found the product failed to cut the risk of heart attacks and strokes compared with standard treatment.
But the 12,500-patient clinical trial also found no significant increased risk of cardiovascular problems or cancer during a follow-up of more than six years. The study was published online Monday in the New England Journal of Medicine and presented, in addition to three other studies set up to look at Lantus and cancer risk, at the annual scientific meeting of the American Diabetes Association.
France-based Sanofi hopes the new research will put to rest safety concerns surrounding its top-selling product, which had sales of about $4.9 billion last year. Lantus is a long-acting form of artificial insulin—known as insulin glargine—that is injected once a day. Diabetes affects about 26 million Americans.
In 2009, studies suggested Lantus might be associated with an increase in cancer, possibly more so than other long-acting insulins. The U.S. Food and Drug Administration began a safety review of Lantus and last year said the 2009 data was "inconclusive."
Three of the new studies used insurance-claims or electronic medical-record databases to look at insulin use and breast cancer, prostate cancer and colon cancer, as well as overall cancer rates. The largest study, the Northern European Study of Insulin and Cancer, followed nearly 450,000 patients in Norway, Sweden, Denmark, Finland and Scotland for more than three years. "It showed absolutely no association at all," said Peter Boyle, the study's principal investigator and president of the International Prevention Research Institute, in France.
A study by Kaiser Permanente Northern California Division of Research looked at data from 115,000 people taking Lantus or another long-acting insulin. It compared new insulin users as well as patients who had switched to Lantus from another insulin. Overall, researchers found no increased cancer risk, except for a small increase of breast cancer among new insulin users. Laurel Habel, a Kaiser Permanente research scientist and the lead researcher, said the increase is likely a chance finding; a true increase in risk would show up in other patient groups.
A study, led by University of North Carolina researchers, looked at a MedAssurant database of more than 50,000 patients in Louisiana and Massachusetts and compared 43,000 people starting Lantus with patients who had started another insulin. The study followed the patients, all cancer-free at the start, for more than a year and found no higher cancer risk.
Dr. Habel said a limitation of the studies was the short follow-up. Cancer usually takes years to develop. Still, the studies' sheer size makes Lantus one of the most-studied insulins on the market, doctors say.
Dr. John Buse, director of the diabetes center at the University of North Carolina School of Medicine, said diabetes patients are already at higher risk of cancer. Older age and increased body weight are factors linked to the development of both Type 2 diabetes and cancer, he said.
