For Widely Used Drug, Question of Usefulness Is Still Lingering
When the Food and Drug Administration approved a new type of cholesterol-lowering medicine in 2002, it did so on the basis of a handful of clinical trials covering a total of 3,900 patients. None of the patients took the medicine for more than 12 weeks, and the trials offered no evidence that it had reduced heart attacks or cardiovascular disease, the goal of any cholesterol drug.
The lack of evidence has not stopped doctors from heavily prescribing that drug, whether in a stand-alone form sold as Zetia or as a combination medicine called Vytorin. Aided by extensive consumer advertising, sales of the medicines reached $5.2 billion last year, making them among the best-selling drugs in the world. More than three million people worldwide take either drug every day.
But there is still no proof that the drugs help patients live longer or avoid heart attacks. This year Vytorin has failed two clinical trials meant to show its benefits. Worse, scientists are debating whether there is a link between the drugs and cancer.
Read more from the NY Times article.
Cholesterol-lowering drug given cancer all-clear
Saw this article on Nature this morning which claims to clear these class of cholesterol lowering drugs from the cancer scare reported earlier...
...Pedersen says he was also unsurprised when the apparent association turned out to be a statistical blip, as the sample size in the SEAS study was far too small to detect modest increases in risk with any certainty.
The media alarm and associated political pressure prompted the management teams of two large ongoing double-blind clinical trials involving ezetimibe to take the unusual step of 'unblinding' their trials several years before they are due to end. They provided data on cancer incidence for analysis.
Those two trials were the UK-based Study of Heart and Renal Protection (SHARP) study, with 9,264 patients, and the US-based Improved Reduction of Outcomes: Vytorin Efficacy International Trial (IMPROVE-IT) study, with 11,353 patients so far. The link with cancer did not emerge in these larger groups.
"I think many of us are starting to find that things are going too far," says Oxford epidemiologist Rory Collins, an author on the NEJM paper that combined the results from SHARP and IMPROVE-IT. "A few years ago data-watch committees would never have agreed to unblind a clinical study." But, he notes, clinical trails have recently become much more sophisticated, with clinicians trying to wring as much information as possible from them – and they sometimes become victims of their success. "If you interrogate your study hard enough, under torture it will confess – but that confession won't be worth the paper it is written on."
-JBH
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