While I was (very worthily) working out at the gym last night I noticed that November’s Smart Money had an article on Lipitor. Given that Lipitor is the single biggest product in health care, currently at $8 billion in revenue, it caught my eye. So I stuck in the reading tray on the elyptical trainer and read away as I elypted. The article (not available on-line) basically said that in a number of cases Lipitor has caused extreme muscle pain and (more devastatingly) alzheimers’ type memory loss in several patients. The article suggested that high doses (above 20mg of Lipitor) actually have the equivalent of 40mg of Zocor, one of its major rivals, yet Zocor can also be obtained in much lower doses (5mg and 10mg) which have virtually the same effect in lowering cholesterol.  Why doesn’t Pfiizer make Lipitor in lower doses?  Bob Erlich, now an industry consultant  running DTCPerspectives Magazine but the guy responsible for Lipitor’s launch at Parke-Davis is quoted as saying essentially (I’m paraphrasing here) that one dose made it easier for the physicians to prescribe as they didn’t have to bother matching patient and dosage.

The article goes on to suggest that independent (i.e. non-pharma funded researchers) have established the high dose to muscle pain link and that the memory loss issue is well known. Behind this is a strong hint that Pfizer is too big to fight either in the dissemination of the message to doctors, or in the law courts–apparently no lawyer will sue until the FDA has withdrawn the drug from the market.  Pfizer for its part acknowledges that the muscle pain is a recognized side effect, but claims that the memory loss–which the article focuses on as it’s pretty devastating–has nothing to do with Lipitor. However, everyone remembers that another statin Baycol was on the market until it was found that in a few cases it caused severe liver damage and was recalled.

It doesn’t take long googling to find several dissatisfied Lipitor users with intense muscle pain and others with transient or long-term memory loss. Unfortunately the Smart Money article doesn’t give any denominators, so there’s no real evidence other than these anecdotal stories about whether significant numbers of people have had these reactions to Lipitor.  So despite the heart-rending stories, you can’t draw any conclusions. Also don’t forget that in the grander scheme of things (if you believe the conventional wisdom that lower cholesterol reduces heart disease), Lipitor is saving thousands of lives for each one it hurts–if it does hurt. This argument is played out in this article on theheart.org (long registration process required.)

From a business perspective what’s important here is the perception of risk.  If statins work for millions and millions of people but a few people allegedly suffer from its side-effects, that’s really the same story that existed for Baycol.  The FDA has been criticized for allowing too many drugs on the market that have to be withdrawn.  Almost always the reason for the withdrawal is a nasty side-effect (e.g. death!) for a very small minority of patients. For Pfizer and its $8 billion drug, there is a very low but existing risk that this could be the end result for Lipitor. Pfizer’s stock has been off slightly in recent months on fears that some patent lawsuits might hurt Lipitor and Zoloft.  Of course that’s nothing to what would happen if Lipitor had to be withdrawn, so watch this wildcard.