Late last week, results from several European studies showing a possible link between Lantus (insulin glargine) and cancer were published online in the journal Diabetologia. Health agencies such as the U.S. Food and Drug Administration (FDA) and the International Diabetes Federation (IDF) have been swift in their response to the release of this information, indicating that the studies are not conclusive and that people with diabetes should not stop taking Lantus without speaking to their doctors.
The first of the studies in question, from Germany, involved 127,031 people with diabetes who used insulin; it found that cancer was more common in people using Lantus than in those prescribed a comparable dose of human insulin. Subsequent to this study, additional research into the subject was carried out using information from patient databases. A study from Sweden looked at 114,841 people being treated with insulin, and found that those using only Lantus were almost twice as likely to be diagnosed with breast cancer. Research from Scotland, which included 49,197 people with diabetes on insulin therapy, also found that people taking only Lantus were more likely to have cancer. However, this finding did not achieve statistical significance. (A result is statistically significant if it is unlikely to have occurred by chance.) A final study from the United Kingdom that involved 10,067 people with diabetes did not find a link between the use of Lantus and the development of cancer.
On June 26, the American Diabetes Association issued a statement “caution[ing] against overreaction until more information is available.” And the FDA recently cast doubt on the research findings, saying that the studies may have been too short to assess whether a cancer risk does in fact exist with the use of Lantus. The European Association for the Study of Diabetes has requested further study into the matter.
For more information, see the published papers on Diabetologia’s Web site, the IDF’s official statement on the situation, and the article “Lantus Insulin: A Possible Link with Cancer — Requires Further Investigation.”