A simple PubMed search shows three scientific papers in the NIH’s database on microRNA in 2001, and an exponential curve rising from there to 1,000 papers in 2007, Xanthopoulos says. By late 2006, early 2007, Isis CEO Stanley Crooke and Alnylam CEO John Maraganore realized that each of their companies had critical technologies that could be used for microRNA drug development. “It was too big of an opportunity to address by small groups within the companies,” Xanthopoulos says. “There was tremendous interest from VCs. Big ideas don’t come along that often. Once every five or 10 years, maybe. To have a huge idea, and have the technologies here that you can plug and play is unheard of. That’s what exciting about Regulus.”
I asked Xanthopoulos help me understand the biology of what he’s talking about.. MicroRNAs, he explained, have evolved over hundreds of millions of years to regulate the on-off switches of genes. They play complex roles, not well understood by biologists, that let them, for instance, fine-tune the immune system’s T cells to attack foreign invaders like viruses while sparing the body’s own healthy cells, Xanthopoulos says. It’s a complicated, delicate balance that can be profoundly disturbed if just a few mircoRNAs go awry. “Think of an orchestra, a symphony, where 100 musicians are playing in harmony, and the conductor knows who’s playing what instrument, and at what frequency,” Xanthopoulos says. “If three or four musicians are off key, it will kill the music.”
So Regulus’ idea is to develop antisense drugs that will bind with and block these microRNAs, keeping them from disrupting the symphony and allowing the body to get back into homeostasis, or a balanced state. Conventional small-molecule drugs and antibodies aren’t able to hit these microRNA targets, he says.
There’s plenty of unknown here, and plenty of risk, given that none of these microRNA blockers has ever been tested in humans. Even so, venture capitalists have been pushing hard to get a piece of the action, and at least five companies are pursuing this opportunity, Xanthopoulos says, including Bothell, WA-based MDRNA and Seattle-based Mirina. He expects more to join the fray, but says that his company has key intellectual property in the field. “All of them are going to have to come to Regulus at some point to get freedom to operate,” Xanthopoulos says. “But the field is going to continue to move forward.”
