Stem Cell Company Tests New Drug For Bone Marrow Patients
Osiris Therapeutics Inc is preparing to unveil results from a late-stage trial that could pave the way for the first approved drug to treat a rare condition that affects bone marrow transplant patients, Reuters reported.
The condition, known as GvHD, is a potentially fatal disease in which immune cells from transplanted bone marrow recognize the recipient’s body as foreign and attack it.
The new drug, Prochymal, is designed to work by interacting with the immune cells in the body, reducing inflammation and assisting in tissue repair. Some experts suggest it could even help patients with diseases like diabetes and Crohn’s disease.
Osiris Therapeutics is currently testing the drug in patients with acute GvHD, which usually manifests itself within a few days of a transplant. The gastrointestinal tract, skin and liver are the main organs affected by the immunological attack.
Patients with GvHD who have failed to respond to steroids, which are the standard treatment, are now undergoing trial treatments. If successful, the studies would form the basis for a marketing application with U.S. regulators.
However, the GvHD trials may have a low chance of success given the drug’s lack of efficacy in other indications, according to Jefferies and Co analyst Eun Yang.
A mid-stage study in June showed that Prochymal failed to improve lung function in patients with chronic obstructive pulmonary disorder (COPD), a respiratory disorder that often affects smokers.
The U.S. Food and Drug Administration halted a March trial of the drug in Crohn’s disease because of design flaws.
With positive data from its mid-stage trial that showed 74 percent of the patients achieved complete remission of the disease, some analysts are cautiously optimistic that the drug will succeed in GvHD.
Piper Jaffray analyst Edward Tenthoff said they are more confident in the steroid refractory study because they really believe that these patients do not respond to steroids.
He foresees a 70 percent chance of success for the steroid refractory study and a 50 percent chance for the acute GvHD study. He also expects the company to resume its Crohn’s disease study.
Nash said that in steroid refractory GvHD, the company has shown that very sick children treated with the drug have about a 60 percent survival rate, when the normal survival rate in this population is about 20 percent.
But Osiris has had disappointing results in two indications so far and should the drug fail in GvHD, analysts see lower chances of success in other indications.
Nash said Prochymal really is the company’s main platform and if it doesn’t work here then people will worry that it will not work elsewhere.
Meanwhile, Osiris is also evaluating the drug in five other indications, including Type 1 diabetes and acute myocardial infarction, or heart attack.
GvHD affects some 4,000 people in the United States each year and the market potential is estimated to be between $150 million and $250 million.
Should the drug be approved in other indications, it could generate sales of more than a billion dollars.
Nash said the thought is that the other indications that Prochymal could work in could potentially bring in over a billion dollars a year.
—
On the Net: