From the Caves of Michigan’s Sleeping Bears Comes Kalamazoo’s Aursos, and a Possible New Drug for Osteoporosis

1/27/11

Deep in the wild, frozen woodlands of Michigan’s Upper Peninsula, it seems that even the scientists are a different, heartier breed of human. A few years ago, Seth Donahue, an associate professor in biomedical engineering at Michigan Technological University in Houghton, MI, decided to gather a few of his bravest grad students and sneak into caves occupied by hibernating black bears.

Yes, those kinds of black bears. The ones with all the fur … and claws … and teeth.

But these bears also have something else that Donahue was curious about—something that makes the risks associated with rousing a sleeping bear worth it. He wondered how bears could go to sleep for 4-6 months every year and not suffer any bone loss, given that humans who are immobilized by age or infirmity begin to lose bone after only a few weeks. You won’t see a hibernating bear wake up in the springtime with osteoporosis. So … very quietly … very carefully, Donahue and his team took blood samples to find out why the bears’ bones remained so strong despite their long periods of inactivity.

The secret, it turns out, is parathyroid hormone (PTH), a molecule that helps regulate the body’s calcium stores. Humans have it too, but the bear version differs from humans’ in the number of amino acids, which scientists speculate is one reason bear bones are superior. The next step was to figure out how to bottle that stuff up and make it helpful to an aging human population, with aging aching backs.

And here’s where a bear hunter steps into our story. Well, a bear hunter who also has a track record of launching successful pharmaceutical startups. Ronald Shebuski was director of cardiovascular therapeutics at Pharmacia & Upjohn between 1990 and 1998, and most recently helped launch Afmedica, a Kalamazoo, MI-based biotech startup that was sold to Angiotech Pharmaceuticals “for a nice sum,” he says.

Shebuski has a place up in Lake Gogebic, the biggest lake in Michigan’s U.P., which he rents out to vacationing snowmobilers. He heard about what Donahue was up to over at Michigan Tech—”this guy who was going into bear dens and getting blood,” and just had to find out what this seemingly mad professor was up to. Shebuski was so impressed that he bought the rights to the technology from Michigan Tech. In March 2007, he launched a company, Aursos, with backing from the Apjohn Group, a Kalamazoo-based life sciences business accelerator.

Since its founding, Aursos has been living from grant to grant to fund its development of black-bear PTH (BB-PTH 1-84), with Ann Arbor Spark and the Michigan Economic Development Corp. chipping in a few hundred thousand. Now, the company is out raising $10 million to take it into the next phase. It has just filed with the FDA for orphan drug designation for the drug as a treatment for muscular dystrophy. It’s not quite the post-menopausal osteoporosis market that Aursos is going after long-term, but to do that would take more than $100 million.

“We don’t have those kinds of resources,” Shebuski says. “And so what we have to do is get into the market and show that this is safe and effective, and then we’ll be able to partner, hopefully, with Pfizer or Lilly or a big company like that and take this into the big market, which is really post-menopausal osteoporosis.”

He predicts clinical trials in two years and says that the Muscular Dystrophy Association is “very intrigued by what we’re doing.”

“I think when we treat these kids with muscular dystrophy, not only are we going to see their bones get stronger, but we’re going to see muscles improve,” Shebuski says, basing the prediction on experiments with mice.

Ultimately, he says, he wants Aursos to get in on the growing osteoporosis market, which he says is forecast to be nearly $14 billion by 2014. Currently, there is only one treatment available that is able to stimulate bone growth—Forteo by Eli Lilly, which saw worldwide sales of $411 million with a growth rate of 21 percent from January to September of 2007.

The company is also partnering with Proteos, another Kalamazoo-based biotech company. The two companies recently received a $1.1 million NIH grant to manufacture BB-PTH 1-84. And, as of the first of the year, Aursos’ new president and CEO is Gary Stroy, who had successfully guided Afmedica’s sale to Angiotech. That experience was such a success, Shebuski is assembling much the same team for Aursos.

Shebuski is confident in the technology and believes the funding will come. Meanwhile, he does his circuit between a home in Virginia, the office in Kalamazoo, and his place in the U.P., where he occasionally hunts black bear. He’s only killed two, and they’re both mounted for guests to see.

“People say bear meat’s terrible, but that’s because a lot of guys, when they get a bear, they throw it on their cars and drive it around and show it to everybody.”

No, you have to eat bear meat right away to enjoy the taste, he says. It will take a little longer, though, to take advantage of the animal’s parathyroid hormone.

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  • pal

    Something the article didn’t talk about: I am wondering if you missed a possible application when it comes to space exploration. Loss of bone and weakening is a known problem when it comes to extended space flight as well.