Can Isis Pharmaceuticals' persuade the FDA that a spike in some liver enzyme readouts for patients in late-stage trials of its cholesterol drug mipomersen is a normal phenomenon that shouldn't prohibit approval of the therapy? Reuters takes a close look at the drug, which was partnered with Genzyme in a rich, $325 million pact, and offers Isis (ISIS) plenty of space to make its case.
As the wire service relates, Isis is expected to deliver a barrage of pivotal data on mipomersen from two studies, one for patients who suffer from hypercholesterolemia and another for patients at risk of heart disease. At the six-month stage patients demonstrated a significant, 28 percent drop in 'bad' LDL cholesterol which was triggered by a genetic mutation. A spike in liver enzymes, a classic safety issue that has torpedoed any number of development programs, spooked analysts. But Isis blandly explains that statins can cause a spike in liver enzymes and no one has seen any sign of liver disease in any patients in these mipomersen studies.
"Even today no one can tell you why statins cause liver enzymes to go up," Isis CEO Stanley Crooke told Reuters. "It's a general phenomena associated with adjustment of lipids."
Whether Isis can make an argument like that stick with the FDA, though, is still to be seen. The agency has been skittish on new drug safety for several years now and has shown little appetite for changing its views. And an approval restricted to a relatively small group of the sickest patients would curtail revenue potential. Isis has a lot riding on the data, with analysts estimating 2014 sales of $354 million. Genzyme provided $325 million to Isis to partner on the therapy, which was about equally split between an equity stake and a $175 million upfront back at the beginning of 2008.
- here's the story from Reuters