[Updated 2/10/10 12:15 pm. See below] Genzyme and Isis Pharmaceuticals are making progress in the clinic with their cholesterol-lowering therapy mipomersen, a major potential moneymaker for both firms. Today the companies, which are collaborating on the development of the drug, report that the treatment significantly lowered the cholesterol of patients with a rare condition called heterozygous familial hypercholesterolemia in a Phase III clinical trial.
The study of 124 patients showed that the drug lowered LDL (bad) cholesterol by 28 percent in those who took the drug over a 26-week period, versus a 5 percent increase in cholesterol levels among those who were on placebo. The study also showed that the drug was associated with increases in liver enzymes called transaminases, which can indicate liver damage, yet tests showed that none of the patients suffered from liver dysfunction. (Luke covered how this liver issue, seen in past studies of the drug, has caused some jitters about the treatment on Wall Street.)
The study’s positive results are important because they keep hope alive for both Cambridge, MA-based Genzyme (NASDAQ:[[ticker:GENZ]]) and Carlsbad, CA-based Isis (NASDAQ:[[ticker:ISIS]]) that mipomersen could eventually be marketed for a much larger pool of patients than the population that the two companies are initially targeting. That first group of patients are those with homozygous familial hypercholesterolemia, a genetic disorder affecting one in a million people. In contrast, the trial being described today focused on patients with the more common heterozygous form of the disease, which affects one in 500 people, according to Genzyme.
The companies plan to file for U.S. and European approval of the drug to treat the smaller homozygous population in the first half of 2011, having already completed a pivotal trial of the treatment in those patients last year.
Still, there might be unanswered questions about the liver safety issue. Christopher Raymond, a biotech analyst for market research firm Robert W. Baird, wrote a note to investors today in which he speculated that some of the patients who did not complete this clinical trial due the liver side effects. noted that the liver issue remains a concern. “While full data is being withheld for a scientific meeting,” he wrote, “we expect a portion of these drop-outs were due to elevated liver enzymes, as Isis management was reluctant to completely dispel this concern during today’s conference call.”
Isis’s stock traded at $9.50 per share at 12:09 pm Eastern time, down 13.95 percent for the day. Shares of Genzyme stock traded at $54.49 at 12:09 pm, a price drop of less than 1 percent. [Editor’s note: The last two paragraphs of this story were added this afternoon to include a reaction quote from an analyst and to record stock price changes following this morning’s news about mipomersen.]