Confab reviews safety of diabetes drugs like Merck's Januvia, Novo's Victoza

Pressure is building to take a deeper dive into the cancer risks of incretin mimetics, a group of drugs for Type 2 diabetes that includes blockbusters like Merck's ($MRK) Januvia and Novo Nordisk's ($NVO) Victoza.

A study of insurance records in March raised the specter of higher pancreatic cancer risks, and the FDA has been taking a closer look at the data. Drugmakers are meeting this week with officials of the FDA and the National Institutes of Health to present safety data for their drugs and to discuss what further study may be needed. FDA spokeswoman Morgan Liscinsky told Bloomberg that one possibility is a large clinical trial designed to show patterns of adverse events. Robert Ratner, chief scientific and medical officer of the American Diabetes Association, said: "We need some calm heads and to look at the data and try and make some reasonable judgments out of this."

Potential risks for incretin mimetics, which help regulate blood sugar by stimulating insulin production, were identified years ago, not long after Byetta from Bristol-Myers Squibb ($BMY) hit the market. Their labels already carry warnings for risks of pancreatitis, added after Byetta was tied to 6 patient deaths. But in February a study published in JAMA Internal Medicine found that patients hospitalized with pancreatitis were twice as likely to be using Januvia or Byetta compared to diabetics who didn't have pancreatitis. And pancreatitis is linked to pancreatic cancer. That prompted the FDA to look again.

Liscinsky told Bloomberg in an email that FDA researchers have not found a direct link between the use of incretin mimetics and pancreatitis, pancreatic cancer or thyroid cancer. "There have been several hypothesis generating studies, as well as many negative studies exploring these signals" in humans, she said.

Drugmakers expressed a willingness to cooperate with the FDA on the matter, while defending the safety of their products, which are popular and successful.  According to EvaluatePharma, Merck last year raked in more than $4 billion from Januvia, while Victoza earned nearly $1.8 billion for Novo Nordisk. Alan Moses, global chief medical officer for Novo, told Bloomberg that patients have been unduly frightened by overzealous interpretations of data. "That's a real challenge for patients out there who are taking this medicine and we have no conclusive evidence that there's a problem and they're being scared to death."

- read the Bloomberg story

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