BioDelivery Sciences International announced Tuesday that it has extended the patent protection for its experimental treatment for chronic pain, which will result in the company receiving a $15 million milestone payment from partner Endo Pharmaceuticals.
BioDelivery's patent for BEMA Buprenorphine has been extended by seven years to 2027.
In January, BioDelivery announced that it had licensed BEMA to Pennsylvania-based Endo. The deal included a $30 million upfront fee and future payments totaling $150 million if certain milestones are met.
With this latest $15 million payment, BioDelivery has now received $45 million in payments from Endo.
BioDelivery projects that BEMA has the potential to generate peak annual sales of $500 million. Endo will manufacture and sell BEMA and will pay BioDelivery royalties in addition to the milestone payments.
Buprenorphine already is an approved pain reliever, but the version available today is delivered via a patch worn on the skin for seven days that many patients dislike. BioDelivery's version consists of a film put in the inside of the cheek twice daily.
BioDelivery plans two Phase 3 tests beginning midyear, each involving hundreds of patients. The tests are likely to take 12 to 18 months to complete.
If all goes well, the drug could be positioned to submit an application for marketing approval with the Food and Drug Administration in the second half of 2014.
BioDelivery's deal with Endo came just three months after the drug company released disappointing test results that sent its stock tumbling. BioDelivery's shares more than doubled after the Endo deal was announced.
The company's stock was up 6 percent in early trading Tuesday. The shares have increased 285 percent this year.

Business reporter David Bracken came to the N&O in 2004. He covers commercial and residential real estate. Contact David at 919-829-4548 or