New details on the side effects of the diabetes drug Avandia have been released (New Scientist 18 July 2007), indicating it can cause 50% more weight gain than similar medications and double the risk of dangerous fluid retention in the body. A team of researchers led by Bernd Richter at Heinrich Heine University in Dusseldorf, Germany, found the latest bad news to report about Avandia.
The team reviewed 18 studies, which had an average follow-up time of about six months. They found the risk of dangerous fluid retention in the body – a condition known as oedema – doubled in those taking the Avandia, compared with patients on other diabetes medications. The diabetics taking Avandia had a 7% risk of oedema – five times higher than those taking placebos.
Oedema is characterised by swelling of the ankles and legs, but can lead to more than just discomfort. Richter explains that the extra fluid in the body can create more work for the heart, causing a shortness of breath and possibly heart failure.
His team’s analysis also showed that patients receiving Avandia gained 50% more weight, on average, than their counterparts on other diabetes medications. The review of 18 previous studies, involving 8000 patients, also echoes earlier warnings that the drug can elevate the risk of bone fractures and heart problems.
But GlaxoSmithKline, the maker of Avandia, says the analysis included too few long-term studies to produce reliable results. Perhaps we could consider this argument – “the analysis included too few long-term studies to produce reliable results”.
Forgive me, but surely short-term studies were what Glaxo relied on to prove the safety of the drug and get it licensed in the first place? Now the company is saying that we can’t rely on short-term studies to produce reliable results… you can’t have it both ways, can you now Glaxo?
Richter, meanwhile, believes that the short-term results he analysed in his review offer enough reason to reduce the widespread use of Avandia, a popular medication in the US where up to 20 million people suffer from diabetes.
“We don’t have [enough] long-term data, and in the meantime the public takes part in a large-scale experiment,” he adds.