Archie

Pfizer Needs Isis More Than Isis Needs Pfizer

I have been patiently waiting for the results from the studies ISIS started in 2006 to measure liver fat in patients treated with mipomersen. Mipomersen lowers cholesterol levels in blood by blocking the movement of fat and cholesterol out of the liver. In theory this should increase the amount of fat in the liver which is not a desirable side effect. For this reason ISIS intiated a study in May 2006 to specifically examine this issue. The mipomersen liver fat study was originally supposed to be completed in February 2008 but has been pushed back twice and the completion date is now listed as March 2010. The company consistently implies that the drug (contrary to its known mechanism of action) lowers liver fat but has produced no data in humans to support this. Pfizer knows this and, in my view, correctly passed on mipomersen. How much is ISIS worth if mipomersen increases liver fat? Probably less than it is trading for now. In that case its use will be limited to those patients where the risk of increasing liver fat outweighs the benefit of cholesterol lowering. In this case mipomersen would essentially be an orphan drug, not the blockbuster that so many people are wishing for.