The FDA told Biogen Inc. it expects to finish its review of the application for Amevive within six months, opening the door for a launch late this year or early next year.
The notification is in response to additional information submitted by Biogen in reference to a complete response letter issued in June for Amevive (alefacept), a psoriasis drug. According to Biogen, the agency now considers the application a "Class 2 resubmission," meaning review completion is required in six months.
Biogen, of Cambridge, Mass., views the development as positive for its drug candidate. "We feel this is great news and it brings us one step closer toward the approval of Amevive," Amy McKnight, a spokeswoman for Biogen, told BioWorld Today. "We've said all along that we expect approval by either late 2002 or early 2003. We never leaned more toward one date or the other."
While McKnight would not characterize the news as a delay or setback, others have said it could cost Biogen some of the psoriasis market. The company's stock (NASDAQ:BGEN) closed Friday at $33.12, down $1.27.
Mark Schoenebaum, a biotech analyst with CIBC World Markets in New York, told BioWorld Today that Enbrel, a product of Amgen Inc., of Thousand Oaks, Calif., could be used off-label to capture some of the psoriasis market. Enbrel, currently indicated for rheumatoid arthritis, is the subject of a Phase II/III study in psoriasis.
Nevertheless, Schoenebaum did not indicate that the news was bleak. "In our view, there are really two choices. [Amevive] could have gotten a Class 1 or a Class 2 - so a Class 1 would have represented the best-case scenario, but I think most people view that as less likely," he said. "A Class 1 really would have represented an unexpected upside."
Under a Class 1 resubmission, the agency would have been required to respond to Biogen within two months.
Biogen filed its biologics license application in August 2001, and in May of this year the Dermatologic and Ophthalmic Drugs Advisory Committee voted 8-to-2 to recommend approval to the FDA. The agency is not bound by the committee's vote. (See BioWorld Today, May 24, 2002.)
Amevive is designed to selectively target the CD45R0+ subset of T cells (memory-effector T cells), and Biogen is asking to sell it as a treatment for patients with moderate to severe chronic plaque psoriasis who are candidates for phototherapy or systemic therapy.
Back in June when Biogen received the complete response letter, the company wasn't quick to discuss any issues that were raised. In fact, the company released only a few statements describing the content as requesting "clarification and information related to data Biogen previously submitted." (See BioWorld Today, June 17, 2002.)
When asked about the letter Friday, McKnight responded that the company wasn't going to comment short of saying additional clinical trials were not requested.
However, Schoenebaum said that the team at CIBC hypothesizes that the agency asked additional questions about manufacturing, the label and postmarketing studies. Furthermore, he believes there may have been some questions and concerns related to possible T-cell monitoring for Amevive patients.
FDA reviewers and advisory panel members in May discussed whether Amevive could cause a reduction in a patient's T-cell counts. Biogen has long claimed that the product affects only a subset of T cells that cause disease.
"It is our belief that the FDA will mandate some form of T-cell monitoring for patients," Schoenebaum said.
He expects Amevive to win regulatory clearance. "In the vast majority of cases the FDA follows the advisory committee's recommendations. So based on that, we would be surprised if Amevive were not approved. We are modeling approval for late first quarter next year," he said.
CIBC World Markets estimates first-year worldwide sales at $85 million, and peak worldwide sales at $300 million to $500 million.
The National Psoriasis Foundation in Portland, Ore., estimates that 7 million people in the U.S. are affected by psoriasis, a noncontagious, chronic skin disease. The most common form is plaque psoriasis, which is characterized by inflamed patches of the skin topped with silvery white scales.
According to the foundation, only an estimated 1.5 million of those suffering from the disease are being treated.
Xanelim, a humanized monoclonal antibody being studied by XOMA Ltd., of Berkeley, Calif., and Genentech Inc., South San Francisco, also is in development for psoriasis.