Seattle Genetics’ New ‘Empowered Antibody’ Looks Clean in FDA Staff Documents
The FDA staff has been known to dish out some unhappy surprises in briefing documents ahead of FDA advisory committees, and to make withering comments about the inadequacy of new drugs, but there wasn’t really any of that in this morning’s analysis of a new drug application from Seattle Genetics (NASDAQ: SGEN).
The FDA staff offered up its overview this morning in briefing documents posted online 48 hours in advance of a meeting of the Oncologic Drugs Advisory Committee, which will be asked Thursday to recommend whether Seattle Genetics’s new drug for rare lymphomas deserves a spot on the U.S. market. The company is seeking clearance to start marketing brentuximab vedotin (Adcetris) as a new drug for Hodgkin’s lymphoma, and anaplastic large cell lymphoma. For both uses, the FDA is asking its panel simply whether it should grant what’s known as an “accelerated approval” with certain conditions that must be met, a regular approval, or no approval.
Regulators took note that Seattle Genetics’ two linchpin clinical trials are “single-arm” studies, meaning they don’t randomly assign patients to the new drug or a control group for comparison, which provides the gold standard of medical evidence. There can be exceptions, the FDA said, in cases of rare diseases (where it can be hard to enroll enough patients), and when a new drug offers a “pronounced treatment effect.” It will be up to the panel, and ultimately the FDA itself, to decide whether Seattle Genetics fits that bill.
The agency, in its briefing documents, outlined some of the drug’s side effects—including nerve damage in the fingers and toes, as well as depletion of infection-fighting white blood cells—all of which have been already been reported at medical meetings. For more of the details, check the FDA panel preview story that ran earlier today. If approved, this will be Seattle Genetics’ first marketed product in its 14-year history, and would have a chance to be the biotech industry’s first commercially successful example of an “empowered antibody” which combines the targeting capability of an antibody with a toxin to give the drug extra tumor-killing kick.
The FDA’s advisory panel will review the presentation of the FDA staff, and from Seattle Genetics, in public sessions on Thursday. The agency said it plans to offer a live webcast of the hearing.