First, Merck was dealt a harsh rejection of Coredaptive, a combination of niacin and laropiprant that had been high up on the drug giant's list of potential blockbusters. Then Genzyme and Isis felt the FDA's wrath when the agency voted thumbs down on mipomersen, another cholesterol drug. Mipomersen will be delayed for several years as the drug developers conduct additional trials.
The back-to-back rejections had some analysts wondering whether the FDA is toughening up on the approval of new cholesterol drugs. It appears that it's no longer sufficient for a drug entering an already-crowded market to be safe and effective; the FDA wants to see a clear benefit over existing medications. These days, it isn't enough for companies to show that their drugs lower bad cholesterol. Drugs must demonstrate better outcomes, thanks largely in part to the recent dust-up over Vytorin. A study conducted by Merck and Schering-Plough showed that when it comes to arterial thickness, there was no significant difference between treatment with generic simvastatin (Zocor) and Vytorin, which combines Zocor and Zetia (ezetimibe).
"FDA has long approved drugs based on their ability to lower so-called bad cholesterol, which is widely believed to reduce heart attack and death," noted the AP. "But the Vytorin results suggest the connection between higher cholesterol and negative outcomes may not be as concrete as initially thought."
FDA staffers say there's been no official change in the agency's policy, but drugmakers may be facing long delays if they can't prove their drugs are significantly more effective that those currently available.