Biogen Idec Inc said on Wednesday its experimental treatment for patients with hemophilia B, a rare inherited blood disorder that impairs coagulation, met the main goal of controlling bleeding in a late-stage trial.
A single injection of the long-lasting clotting factor, being developed in partnership with Swedish Orphan Biovitrum, controlled bleeding in 90.4 percent of all episodes.
Biogen, which makes the multiple sclerosis drugs Avonex and Tysabri, said it plans to submit an approval application for the hemophilia drug to the U.S. Food and Drug Administration in the first half of 2013.
The study, known as B-LONG, enrolled 123 male patients age 12 and older, divided into four groups that were treated at different intervals. Overall, 93.5 percent of patients completed the study.
The companies said the treatment was generally well-tolerated, but one serious event was considered to be possibly related to the drug. A patient experienced obstructive uropathy but continued treatment with Biogen's drug and the condition was successfully treated. Obstructive uropathy is a condition in which the flow of urine is blocked, causing it potentially to back up and injure the kidney.
The most common side effects were nasopharyngitis, influenza, joint pain, upper respiratory infection, hypertension and headache.
The companies said they expect to file an application with European health authorities after completion of a study in children younger than age 12, as required by the European Medicines Agency.
Hemophilia B is one of two forms of the disease. The company is also testing a drug for the more common hemophilia A, and expects to present results from that trial by the end of the year.
Hemophilia B is caused by a lack, or insufficient amount, of the blood coagulation factor IX protein, needed for normal blood clotting. Patients with hemophilia A lack or have reduced levels of coagulation factor VIII.
There are currently multiple hemophilia treatments on the market, but they must generally be given multiple times per week by infusion. Hemophiliacs, including children, are taught to inject themselves in a burdensome process that involves finding a vein and piercing it with a butterfly needle.
Current treatments for hemophilia B generate about $1 billion a year, according to Biogen, while the market for hemophilia A is worth about $5 billion.
Biogen's products are designed to cut the number of infusions needed to control bleeding. Existing Factor VIII products must be taken as many as three to four times a week. Factor IX products must be taken intravenously two or three times a week.
The B-LONG trial showed that the median dosing interval for patients taking Biogen's drug is only once every two weeks, an improvement that Geoff Meacham, an analyst at J.P. Morgan, said could be "game changing" based on physician feedback.
However, Meacham said that while the data is encouraging, "hemophilia is a new disease area for Biogen, so there is some commercial risk associated with the potential launch."
Glenn Pierce, chief medical officer for Biogen's hemophilia program, said the company has hired multiple experts in the hemophilia field and is confident it can manage a successful launch.
Swedish Orphan Biovitrum, or Sobi, may choose to market the drug in Europe, Russia, the Middle East and Northern Africa. If it does so it will contribute to the cost of research and development, a reimbursement that would be recouped by Biogen through adjustments to the cross-royalty structure for the first six years.
It remains to be seen whether results from the hemophilia A trial will replicate those from the hemophilia B trial, an uncertainty that caused Biogen's shares to give up early gains and close 0.8 percent lower at $151.62 on the Nasdaq on Wednesday.
Pierce said that while the trials are different, the technology behind the two drugs is the same.
"One can never predict the outcome," he said. "But we're hopeful that we will see good results."
(Reporting by Toni Clarke in Boston; additional reporting by Esha Dey in Bangalore and Debra Sherman in Chicago; editing by Maureen Bavdek and Matthew Lewis)