Osiris Therapeutics Inc. is gearing up for expanded trials for a stem cell treatment used to treat pain in osteoarthritis patients after promising results from early-stage testing.
Chondrogen, a preparation of adult stem cells that is injected into the knee, produced a significant reduction in knee pain compared with an existing treatment, according to the company.
C. Randal Mills, president and chief executive officer of the Columbia company, termed the results "clinically and statistically significant." He said Osiris will "start working immediately" on the next stage of testing, which is likely to begin in the first half of next year and take a year or more to complete. The results from the early-stage trials, with 55 patients, were scheduled to be announced overnight.
The potential market is large. Mills said the treatment against which Chondrogen was tested, hyaluronic acid (HA), has sales of about a half-billion dollars a year.
About 20 million Americans have osteoarthritis, according to Mills. It is a condition in which cartilage in joints has deteriorated, causing bones to rub against each other, producing pain and limiting movement. Chondrogen is being tested only on knees. But should those tests lead to approval, it has potential for use in other joints as well.
The new early-stage results represent something of a reversal of fortune for Chondrogen. In February, the company announced early results from the same 55-patient trial, which failed to show that Chondrogen helped regenerate knee cartilage. Those disappointing results pushed Osiris shares down about 10 percent in one day, and the share price has generally languished since. Its stock closed at $10.24, down 42 cents, in trading on the Nasdaq stock market yesterday.
While that part of the trial used data from magnetic resonance imaging (MRI) studies of knee joints, the latest results are based on patients' reports of their level of pain and on monitoring of bony changes associated with arthritis.
The trial found 21 percent of the control group, treated with HA, showed such bony growths, but only 6 percent of those treated with Chondrogen.
Osiris is also testing a "sister product," Prochymal, an intravenous form of the same stem cells from adult bone marrow, as a heart treatment.
With headquarters and labs in Columbia and a manufacturing facility in Baltimore, Osiris employs about 140 people.