Experimental Cholesterol Drugs May Cause Amnesisa: FDA Investigates

Cholesterol-lowering drugs slated to enter the U.S. market in the future have gained the attention of the Food and Drug Administration (FDA). According to a regulatory filing Friday, the FDA is concerned that the experimental drugs may be causing severe cognitive adverse events in some patients.

Alirocumab, the drug cited by the FDA, is one of a new group of drugs called PCSK9 inhibitors. These experimental drugs are designed to block proteins in the bloodstream that retain "bad" cholesterol, effectively reducing the chance of cholesterol build up along arterial walls. This, in  turn, help prevent stroke or cardiac arrest.

Alirocumab is currently undergoing large-scale human clinical trials, testing the safety of the drug before the FDA can make any final decisions about whether it is effective and safe enough to be made available to U.S. citizens suffering from high-cholesterol problems. According to investor updates from Sanofi SA and Regeneron Inc., the companies co-developing Alirocumab, the drug had been testing well regarding its intended purpose.

However, things may have turned for the worse now that the FDA is concerned about the drug's adverse effects. According to a regulatory filing filled by the FDA Friday, Sanofi - Regeneraon will work with the FDA to conduct further testing that should assure federal regulators that the chance of adverse cognitive side-effects, such as memory loss, confusion, and full-blown amnesia, are extremely rare, if present at all.

Amgen Inc. is also developing a PCSK9 inhibiting drug, and said in an email to the Wall Street Journal that the company was aware of the risks these drugs pose. Still, a Amgen spokeswoman assured reporters that the drug has only shown a less than 1% chance of any negative cognitive side effects at all, after a recent 52-week clinical study, but the company will continue to monitor the event.

Sanofi and Regeneron have acknowledged in recent investor reports that if a risk of negative cognitive side effects is discovered, it could delay or even terminate the development of alirocumab, but they remain positive about testing.