The research involved collaborators from Regulus, Alnylam, the University of Wuerzburg in Germany, the University of California, San Francisco, King’s College in London, Heidelberg University in Germany, Northwestern University in Evanston, IL, and the Rockefeller University in New York.
“This exciting research defines an entirely new potential strategy for intervention, where antagonism of a single microRNA could result in correction of the disease pathways of heart failure,” said Eugene Braunwald, a professor at Harvard Medical School, in a statement released by Regulus and Alnylam.
The researchers found that when mice were put into heart failure—a chronic condition in which the heart becomes enlarged and fails to efficiently pump blood—they got better in a hurry when they were given a drug to block mir21. They were given three daily injections of the drug close to the heart, and within two to three weeks, their hearts shrunk 30 percent to 40 percent back to normal size, and had their blood pumping ability restored to normal, Xanthopoulos says. “It’s a spectacular finding,” he says.
Before everybody gets too carried away, there always caveats with this type of research. This paper only followed mice for two to three months, so there’s no sense of how long this effect might last. The next step will be to see if the finding can be replicated in pigs, a larger animal with heart tissue that more closely resembles a human. The earliest point this drug could enter human clinical trials would be within a couple years, Xanthopoulos says. Since no microRNA drug has ever been tested in people, it’s probably a safe bet that the FDA will be a little extra careful before allowing the company to go ahead.
Regulus isn’t even saying for sure if mir21 is its lead therapeutic candidate. It’s one of a handful of leading projects at the company, Xanthopoulos says, along with a program against the herpes simplex virus (cold sores). We’ll learn more when Xanthopoulos and Alnylam CEO John Maraganore will take questions like these tomorrow morning on a conference call with investors at 8:30 am Eastern time, before the markets open.
