It seems pretty clear that when patients who take Ambien CR to both fall and stay asleep are told their new generic will do the same thing, they won’t be satisfied with a pill that fulfills only half of that promise.
But that’s just what they may get with generic zolpidem. Ambien CR is specially formulated so that the medication it contains is dispensed so that patients both drop off and remain asleep so any variation in these concentrations can mean patients may wake up long before they want to.
Yet, the FDA only tests the concentration of generic zolpidem at 1.5 hours and then 1.5 hours to when the drugs stops being measurable in the system, which does very little to ensure that the drug concentrations match those of the branded drug over course of the 7 or 8 hours that it is patients’ systems. Especially since 90 percent of the drug enters the body after 1.5 hours.
Who thinks this is acceptable?
Similar concentrations at one single point is hardly strong evidence that the two drugs are actually bioequivalent.
What’s more, generics that dispense their contents in a different way can actually be dangerous since the drug may linger in patients’ systems longer than it should. That can mean day time sleepiness and reduced coordination.
Sanofi-aventis, which makes Ambien CR, has a simple solution and a reasonable request: test generics for the concentration during 0-3 hours, 3-6 hours, and more than 6 hours. As Gerard Sanderink of sanofi-aventis explained this afternoon, this would assure that the generic was bioequivalent on all of the main dimensions of Ambien CR, sleep initiation, sleep maintenance, and residual effects.
It’s a proposal that’s good for patients – and innovator companies. Why is the FDA dragging its feet?
