Washington Editor

Despite reassurances from Corixa Corp. that there’s nothing wrong with its lead drug candidate, Bexxar, the Seattle company’s stock tumbled Thursday on news that the FDA has delayed an application hearing for the product.

According to a statement released by Corixa after the market closed Wednesday, the FDA’s Oncologic Drugs Advisory Committee (ODAC) can’t hear the application in February because the agency’s reviewers haven’t made it through the “extensive amount of material” submitted by the company. Bexxar (tositumomab and iodine 131 tositumomab), an investigational radioimmunotherapy, is being studied for the treatment of low-grade or transformed low-grade non-Hodgkin’s lymphoma.

“The FDA explained to us in a phone call that due to the extent of the response that we submitted back in September, they are not able to fully review the information in time to be able to schedule us for a February panel review,” Jim DeNike, Corixa’s director of corporate communications, told BioWorld Today.

“In this business you are conditioned to prepare for anything, but we are obviously disappointed that we will not get the opportunity to present at the February panel hearing,” DeNike said.

Corixa’s stock (NASDAQ:CRXA) closed Thursday at $12.38, down $2.39, or about 16.2 percent.

ODAC’s next meeting is tentatively scheduled for June 6 and 7, however, there’s no guarantee that Corixa will make it onto the agenda. Furthermore, DeNike said it’s too early to speculate whether the FDA will call a special meeting of ODAC between February and June to hear the Corixa case.

So what does this mean for Corixa and patients in need of Bexxar?

Leaning on the conservative side, DeNike said Corixa believes it will launch in 2002. “It’s unclear at this point how far the launch will be delayed because we don’t know what the next steps are going to be. Assuming that we get on a June panel or a special panel, and assuming that the panel review is positive and the recommendation is approved, we could launch this year.”

But Mark Monane, a research analyst with Needham & Co., of New York, stepped out on the ledge and estimated a delay of only three months, adding that the delay is no reflection on whether Bexxar works or not.

On the contrary, the problem seems to be the volume of supportive data and information Corixa sent in response to the FDA’s March 2001 request for additional clinical and manufacturing information related to Bexxar. The FDA originally accepted the Bexxar BLA in November 2000 and assigned it six-month priority review status.

The Prescription Drug User Fee Act gives the FDA six months to respond to a BLA, and according to Monane, this recent delay by the agency is perfectly acceptable.

“The FDA does have challenges in terms of reviewers,” Monane said. “There are a record number of BLAs and [new drug applications] and [investigational new drug applications], but there are the same number of FDA staff. So the double-edged sword of innovation and biotech is that the FDA has a bigger workload and by definition is more stressed than it was before.”

Corixa isn’t the only company developing a non-Hodgkin’s lymphoma treatment that received disappointing news from the FDA this week. Corixa’s main competition, San Diego-based IDEC Pharmaceuticals Corp., Tuesday was notified it would have to delay the launch of its product, Zevalin, due to manufacturing compliance issues at the company’s fill/finish provider, Catalytica Pharmaceuticals Inc., of Greenville, N.C. (See BioWorld Today, Jan. 10, 2002.)

Zevalin also is an investigational radioimmunotherapeutic agent for the treatment of non-Hodgkin’s lymphoma. Analysts predict a second quarter launch for Zevalin, which still places it ahead of Bexxar. However, Monane said the success of the drugs will not be determined by their respective launch dates.

“The products are similar, but they both have their pluses and minuses,” Monane said. “In the biotech and pharmaceutical industries it doesn’t mean much to be on the market first. Any good formulary committee is going to look at the drugs together and decide how and when to use it in their institution.”

In other news, Corixa and its Bexxar partner, GlaxoSmithKline plc, of London, in September filed a lawsuit against IDEC for alleged patent infringement on Zevalin. (See BioWorld Today, Sept. 13, 2001.)

DeNike said since September discussions have taken place between the companies, “but there’s no resolution to report.”

Corixa has a healthy pipeline with 16 programs in clinical development and 22 in preclinical development. On Tuesday, Corixa and Rhein Biotech NV, of the Netherlands, revealed highly statistically significant preliminary results of a Phase III study of Corixa’s RC-529 synthetic adjuvant when used in combination with Rhein’s yeast Hansenula polymorpha-based recombinant hepatitis B antigen, the active ingredient of commercially approved hepatitis B vaccines.