By Kim Coghill
Following a year of modifying the biologics license application (BLA) for Bexxar, Coulter Pharmaceutical Inc. and SmithKline Beecham plc Monday announced resubmission of the application.
The companies are seeking marketing approval of the drug for the treatment of patients with relapsed or refractory, low-grade or transformed low-grade B-cell non-Hodgkin's lymphoma. They have requested priority review.
If the FDA approves Bexxar as anticipated by company officials and analysts within the next six to nine months, it will be the first radioimmunotherapy available on the market, according to product developers.
"Submission is an important milestone that begins the clock of FDA approval," said Sylvia Wheeler, director of investor relations for South San Francisco-based Coulter. "This [drug] is a leader based on its safety and efficacy profile."
A month after its original submission in July 1999, the FDA requested that Coulter and London-based SmithKline Beecham modify their submission, principally around reformatting data and reorganizing analysis of existing data. However, Jennifer Armstrong, spokeswoman for Smith- Kline Beecham, said there were no requests for additional data from ongoing trials or any demand for new trials.
Regardless, the announcement caused Coulter's stock to dive 32 percent that day to close at $23.50. Monday, however, Coulter's stock (NASDAQ:CLTR) closed at $33.25, down $3.50, or 9.5 percent - though the stock has risen 46 percent in the past month - and SmithKline's (NYSE:SBH) closed at $61.375, up 56 cents.
"We believe Coulter is a strong buy and Bexxar is a safe product," said Dennis Harp, an analyst with Deutsche Banc Alex. Brown in New York. He expects the drug to generate about $300 million annually after about two years.
"SmithKline Beecham is highly committed to developing and marketing oncology products," Armstrong said. "We have been working in close partnership with Coulter to make Bexxar available for people with non-Hodgkin's who need treatment options."
Bexxar has been designated a fast-track product by the FDA because it targets an unmet, life-threatening medical need, according to Armstrong.
But in a research report, Thomas Dietz, senior managing director of San Francisco-based Pacific Growth Equities Inc., said considering the recent FDA delays (attributed to computer changes), approval of the drug is not likely until the second quarter.
"We believe Bexxar has an excellent prospect of reaching the market by the middle of 2001," according to Dietz. "Coulter appears to be back on track."
Bexxar is a radioimmunotherapy involving an antibody conjugated to iodine-131 (I-131) that attaches to a protein found only on the surface of B cells, including non-Hodgkin's lymphoma B cells. The properties of the I-131 radioisotope allow a patient-specific dose to be determined and administered. Bexxar is believed to work through multiple mechanisms of action resulting from immune system activity of the monoclonal antibody and the therapeutic effects of the radioisotope.
Non-Hodgkin's lymphoma is a form of cancer that affects the blood and lymphatic tissues. It is the sixth leading cause of death among cancers in the United States and has the second fastest growing mortality rate.
Citing statistics from the National Cancer Institute, Wheeler said about 300,000 people in the U.S. are afflicted with non-Hodgkin's lymphoma and about 140,000 have low-grade or transformed low-grade disease.