Back in 2010, when Victoza, a type 2 diabetes drug, was approved, some sources warned about the safety risks of taking this drug. In several animal studies, Victoza caused thyroid tumours. In human studies, many patients developed pancreatitis, a dangerous inflammation of the pancreas.
Despite these worrying results, the American Food and Drug Administration (FDA) gave Victoza the green light, dismissing all the safety warnings from their panel members. At the time, the drug was hailed as a revolution in the treatment of type-2 diabetes,a condition that affects 2.5 million Britons.
Avandia all over again?
Victoza falls in a class of drugs called incretin mimetics (also known as GLP-1 agonist, or DPP-4 inhibitors). These drugs are sold under the names Victoza, Januvia, Byetta, Exenatide and Liraglutide and they work by mimicking incretin hormones to help control blood sugar levels.
Incretin hormones are a group of gut hormones that naturally stimulate the release of insulin in response to a meal. As your blood sugar rises after a meal, the drug prompts your pancreas to release insulin. It also prevents your pancreas from releasing too much glucagon, another hormone, which causes your liver to release stored sugar into your bloodstream. On top of that, it also inhibits DPP-4, an enzyme that destroys the hormone incretin.
These drugs also slow the rate at which your stomach empties after you’ve eaten a meal, which may reduce feelings of hunger. This dampens the rate at which your blood sugar rises after eating.
Sounds great, right?
Three years after this ‘miracle cure’ hit the market, the Journal of the American Medical Association (JAMA) published a study which found that in most cases, hospital admissions for pancreatitis happened within the first 60 days of patients taking the incretin mimetic drug Januvia. The study warned that patients taking this diabetes drug have twice the risk of developing acute pancreatitis.
In response to these results, a spokesperson for Merck, the makers of Januvia, rejected the idea that the drug could cause pancreatitis and added: “Nothing is more important to Merck than the safety of our medicines and vaccines and the patients who use them.”
That’s despite the fact that research published in 2011 indicated that Januvia could increase the risk of pancreatic cancer by 172 per cent and thyroid cancer by 48 per cent.
In fact, the writing was already on the wall for incretin mimetic drugs just one year after their approval, when FDA officials issued a warning, linking Victoza use to an increased risk of pancreatitis, thyroid cancer, and kidney failure.
In another study, published in the journal Diabetes, pancreases from 20 diabetics were examined. In patients treated with incretin therapy there was a 40 per cent increase in pancreatic cells as well as cell damage. Of the 8 pancreases of patients who received incretin therapy, 7 were associated with Januvia. The researchers concluded that “in humans, incretin therapy resulted in ‘marked’ cell proliferation and damage, with a potential for evolution into cancer.”
Now, an investigation by the British Medical Journal and Channel 4 Dispatches has looked into all the findings of these studies, and found that the manufacturers of incretin mimetic drugs (including Merck, Novo Nordisk and Amylin Pharmaceuticals) may have been trying to hide the potentially harmful side effects of these drugs.
Dr Deborah Cohen, the BMJ‘s investigations editor, said that the evidence of these trials “may seem inconclusive” on their own, but added: “When considered alongside other emerging and long standing evidence, a worrying picture emerges, posing serious questions about the safety of this class of drug.”
Dr Fiona Godlee, BMJ editor-in-chief, said the manufacturers had been “unwilling to share their data” and that patients and doctors had “not been kept properly informed about the uncertainties surrounding these drugs.”
Well, that’s no big surprise… It’s sounds like Avandia all over again and as we’ve learned from that experience, if you value your health and your life, it’s probably best not to wait for health officials to ban these drugs. They’ll probably only take action when it’s already too late for thousands of patients.