By Jim Shrine

Data on multiple sclerosis (MS) drugs presented at a neurology conference may result in changes in both the treatment method and the market, both of which could benefit patients.

Biogen Inc.¿s Avonex helped decrease the rate of brain tissue loss in the second year of treatment, while Teva Pharmaceuticals Industries Ltd.¿s Copaxone showed a 35 percent reduction in new lesions and a 33 percent reduction in relapse rates.

Meanwhile, Immunex Corp. released three-year data for the first time showing Novantrone (mitoxantrone) patients experienced sustained reduction in the number of attacks and had their disability progression delayed.

The data were presented at the 51st Annual Meeting of the American Academy of Neurology, in Toronto.

Avonex, Copaxone and Chiron Corp.¿s Betaseron already are approved for treating relapsing and remitting disease. A new drug application seeking approval of Betaseron for the expanded indication of treating progressive disease was filed last June. Immunex said it plans to file by the end of the second quarter, seeking approval of Novantrone in secondary, progressive disease. Avonex is expecting Phase III data from its trial in secondary, progressive MS around mid-2000.

A key discovery from the study of Avonex, presented by researchers at the Cleveland Clinic, was that brain tissue loss occurs before other symptoms of MS arise. That finding was aided by the use of a new diagnostic agent to measure brain atrophy.

That data will give clinicians another reason to treat patients early, rather than waiting until there are severe symptoms, said Peter Ginsberg, senior research analyst at U.S. Bancorp Piper Jaffray Inc., in Minneapolis.

Brain atrophy is irreversible and associated with other symptoms of MS, such as memory loss, slurred speech and reduced muscular control.

Immunex, of Seattle, had presented results from its 194-patient Phase III trial of Novantrone in September, showing quarterly infusions of the drug decreased relapse rate as well as improved neurologic function and mobility as measured by disease progression scales. (See BioWorld Today, Sept. 11, 1998, p. 1.)

The new data involve patients who were treated for two years and then followed for another year.

Lisa Crisera, communications specialist at Immunex, said the data ¿still are preliminary, but we feel like [the study] showed there was some lasting effect on the disease based on the continued improvement of EDSS [Expanded Disability Status Scale] scores, and the fact that patients who received Novantrone were less likely to have a relapse than those who received placebo.¿ The results were seen in both Novantrone arms, she added.

Novantrone first was approved in 1987 for treating acute myelogenous leukemia. The label was expanded in 1996 for treating pain associated with advanced prostate cancer. Sales in the first quarter were $10.8 million.

¿We have met with the FDA a few times, and we feel comfortable filing our data,¿ Crisera said. A submission for MS is expected to take place by the end of the second quarter. ¿We hope to get priority review,¿ she added.

Crisera said Novantrone could enjoy certain advantages, since it would be indicated for secondary, progressive disease and is taken once every three months rather than daily or weekly, like the other MS products.

Lisa Easley, a spokeswoman for Cambridge, Mass.-based Biogen, said, ¿We believe the data is further evidence that Avonex is a good therapy, among a broad spectrum of patients with MS.¿

Of the three FDA-approved MS drugs, Avonex is the clear market leader, with about $304 million in U.S. sales last year. Numbers that Ginsberg provided about a month ago showed Avonex had about 58 percent of the U.S. market, while Betaseron had 25 percent and Copaxone had 17 percent.

Betaseron is marketed by Chiron, of Emeryville, Calif., and Berlex Laboratories Inc., a subsidiary of Berlin-based Schering AG, which reported its worldwide Betaseron sales in 1998 were $410 million, about $15 million more than the sales of Avonex.

Ginsberg said he does not anticipate Novantrone, if approved for MS, will have a significant impact on sales of Avonex, Betaseron or Copaxone, since most use of those drugs is in relapsing and remitting patients.

Biogen¿s stock (NASDAQ:BGEN) gained $8.125 Thursday to close at $107.875. Immunex (NASDAQ:IMNX), which had gained $20.75 Tuesday and $17.375 Wednesday, mostly on the strength of its reported earnings, fell $2.75 Thursday to end the day at $101.625. n