Seattle Genetics batted a clean 2-for-2 today in its appearances in front of an FDA advisory committee.
The FDA’s Oncologic Drugs Advisory Committee voted 10-0 to recommend that Seattle Genetics’ brentuximab vedotin (Adcetris), be cleared for sale as a new treatment in the U.S. for anaplastic large cell lymphoma. That decisive vote came after a morning session in which the panel voted 10-0 in favor of the same drug for a related malignancy, Hodgkin’s lymphoma.
Both of these conditions are quite rare. About 8,500 patients in the U.S. get Hodgkin’s each year, and while about two-thirds get cured by standard chemotherapy, about one-third relapse. About 2,000 new cases of anaplastic large cell lymphoma are diagnosed each year, half get effectively treated with chemo, but once it recurs, patients are only expected to live a little more than three months, according to Barbara Pro, a researcher at Fox Chase Cancer Center in Philadelphia, who studied the Seattle Genetics drug in clinical trials.
The data for the Seattle Genetics drug in this group of patients was striking. The drug completely or partially shrank tumors in 86 percent of the patients studied in a mid-stage trial (50 of 58). Most of the patients (57 percent) went into complete remissions, with no sign of their tumors anywhere on imaging scans. The complete remissions lasted for a median time of 13.2 months, before the tumors began to re-appear, Seattle Genetics said. The main side effect was peripheral neuropathy, a form of nerve damage in which patients feel numbness and tingling in their fingers and toes.
“This drug is wildly active in this rare population. The toxicity is concern, but not a dealbreaker for patients without other options,” said Mikkael Sekeres, an oncologist at the Cleveland Clinic, in explaining his vote at the afternoon hearing.
The FDA has a deadline of August 30 to complete its review of the Seattle Genetics application to start marketing the drug for patients with Hodgkin’s and anaplastic large cell lymphoma. If approved, the new therapy will be Seattle Genetics’ first marketed product after 14 years in business, and it would be in position to be the first commercially successful version of an “empowered antibody” that specifically zeroes in on tumors, mostly spares healthy tissues, and unleashes a potent toxin against tumors.
Trading in Seattle Genetics stock (NASDAQ: [[ticker:SGEN]]) was halted today during the FDA panel’s deliberations, and is expected to resume tomorrow.
