Washington Editor

Corixa Corp.'s stock headed upward Tuesday following news that the FDA accepted additional data as well as responses to concerns raised about the biologics license application for Bexxar, the company's lead cancer product, and thus Corixa dropped its dispute resolution with the FDA.

Corixa's stock (NASDAQ:CRXA) closed Tuesday at $8.30, up $1.42 or 20.6 percent. Meanwhile, the stock for Corixa's partner, London-based GlaxoSmithKline plc (NYSE:GSK), closed at $37.25, down 20 cents.

So, Corixa and GSK now head to the Oncologic Drugs Advisory Committee (ODAC) meeting Dec. 17 with a package deemed acceptable by the agency.

Michelle Burris, chief financial officer for Seattle-based Corixa, told BioWorld Today that the Bexxar biologics license application has been returned to "active" review status and the agency has set May 2, 2003 as the new Prescription Drug User Fee Act goal date for its review of the materials.

ODAC had been scheduled to hear the Bexxar BLA by way of a dispute resolution that Corixa filed in May. However, Corixa said it dropped the dispute Monday once the agency reinstated the active status.

"I would say it is better to go before the committee under the active review status than because of a dispute resolution," Burris said.

Indeed, while representatives from both Corixa and GlaxoSmithKline interpret the FDA's acceptance as a positive step, at least one biotechnology analyst characterized the news as even more.

A prepared statement released by Philip Nadeau, vice president and biotechnology analyst with SG Cowen in New York, said, "Importantly, this means the FDA no longer believes that new clinical trials are necessary to address its concerns."

He added, "We believe that this signals a change in the FDA's body language and increases the chances that Bexxar will receive a positive recommendation at the Dec. 17 ODAC panel meeting."

It was just a month ago that Corixa said it had been assigned the panel date following months of communication with the agency aimed at ironing out wrinkles in the BLA.

Bexxar (tositumomab and iodine-131 tositumomab) is an investigational radioimmunotherapy being developed for the treatment of low-grade or transformed low-grade non-Hodgkin's lymphoma (NHL). Also, Corixa will seek registration for use of Bexxar in low-grade NHL patients who do not respond or progress following rituximab therapy.

The other radioimmunotherapy on the market for NHL is Zevalin, made by San Diego-based IDEC Pharmaceuticals Inc. In September 2001, ODAC voted in favor Zevalin (ibritumomab tiuxetan) for Rituxan-refractory patients and for patients who had not failed Rituxan. (See BioWorld Today, Sept. 13, 2001.)

Nadeau told BioWorld Today that it's difficult to pinpoint the actual differences between Zevalin and Bexxar, "because they have never been compared in a head-to-head trial." Nevertheless, he said, many believe Bexxar stays in the body longer than Zevalin.

Peak worldwide sales of Bexxar are expected to reach $220 million, compared to $365 million for Zevalin, Nadeau said.

If all goes well in the panel meeting and later at the FDA, Bexxar could make it to market next summer. Many had expected Bexxar to end up in front of ODAC last February, but the FDA threw a wrench in that plan when it said agency reviewers had not had time to study all the material submitted as part of the BLA. (See BioWorld Today, Jan. 11, 2002.)

By March, the agency had reviewed all the data and issued a letter stating that additional trials would be necessary for approval. Initially, the FDA said it had insufficient data to adequately evaluate the safety profile. Furthermore, the agency raised questions about approvability of the product, given that other drugs, namely Zevalin and Rituxan, are available for this disease. (See BioWorld Today, March 14, 2002.)

In June, Corixa was notified that it had won the appeal on the agency's decision as noted in the "complete review letter" dated March 12, 2002. (See BioWorld Today, June 28, 2002.)