Cancer Alert Asked as Sanofi, Novo Diabetes Drugs Put to Test
European scientists startled medical professionals and patients in June when they reported in the Diabetologia medical journal that Sanofi-Aventis SAs Lantus, the worlds biggest-selling insulin, may increase the risk of cancer. U.S. regulators delayed a decision on Novo Nordisk A/Ss liraglutide drug until the fourth quarter after cases of thyroid cancer emerged in animal tests.
The cancer link casts a spotlight on glucose-lowering therapies that have become standard care for people who cant control their blood sugar levels with healthy eating or exercise, said Edwin Gale, a professor of diabetes at the University of Bristol, England, and the editor of Diabetologia. Doctors attending this years European Association for the Study of Diabetes meeting in Vienna will discuss whether they need to weigh more closely the risks of such medicines when Sanofi and Bagsvaerd, Denmark-based Novo Nordisk present information on the safety of their long-acting insulins, Lantus and Levemir, on Oct. 1, Gale said.
Dogma
“As a general rule, the dogma has been that anything that lowers glucose is equivalent in terms of benefit,” said Gale in an interview. “Thats now being teased apart. Weve got a number of relatively equivalent glucose-lowering therapies. In the future, were going to be asking hard questions about what the other costs and benefits will be.”
Diabetes therapies metformin, Avandia and Actos may be protective against malignancies, Gale said.
Sales of Lantus, a so-called long-acting analog also known as insulin glargine, and Levemir are growing even after the Sanofi product came under scrutiny in June when four European studies published in the medical journal suggested it may increase the risk of tumors.
Sanofi said Lantus is safe and the studies have “significant, methodological limitations and shortcomings.”
Insulin analogs are tested for carcinogenicity because the hormone has long been known to interact with insulin-like growth factors in the body that play a role in cell growth.
Safety
“There will be data from the manufacturers of the long- acting analogs, which are reassuring as far as they go,” said Gale. “The question will be if they are sufficiently powered to answer the questions” about their safety and possible ties to cancer, he said.
The U.S. Food and Drug Administration, in response to the Diabetologia studies, in a statement on its Web site on July 1 questioned whether a link between Lantus and cancer exists. The reports examined one to three years of therapy, less than what is generally necessary to evaluate a link between cancer and drug exposure, the FDA said at the time. Variances such as patient weight and the dose of Lantus, also may have influenced the findings, it said.
Consensus
“While there is a consensus among leading scientists around the world regarding the difficulties of developing conclusive evidence, Sanofi-Aventis is committed to exploring this matter in depth,” the French drugmaker said.
Treatment for the more-than 200 million diabetics worldwide is designed to help the body convert blood sugar into energy. The drugs are taken for life, as the body gradually produces less of the hormone insulin that naturally controls blood glucose or sugar levels.
The number of people with diabetes worldwide is expected to rise to 350 million in the next two decades, according to Sanofi.
Sanofi is urging doctors to introduce insulin, often regarded as a treatment of last resort, earlier in the onset of diabetes amid evidence it may slow the progression of the disease.
Type 2 diabetes, the most common type, typically develops in overweight, sedentary adults. Most people with this form of diabetes are overweight or obese, a condition that is also tied to cancer. Obesity may have caused 124,050 newly diagnosed tumors last year in Europe, according to research released last week.
Canceled Project