A year after the FDA rejected Athena Neuroscience Inc.'s new drugapplication (NDA) for Zanaflex, the agency Monday informed theSouth San Francisco company the drug was "approvable" pendingagreement on labeling details and plans for collection of post-marketing data.

Athena reported the FDA's decision after the market closed, but thecompany's stock (NASDAQ:ATHN) was up $2.12 for the day to$15.62, a 16 percent jump.

Zanaflex, or tizanidine hydrochloride, is targeted for treatment ofspasticity, which usually is associated with spinal chord injuries andmultiple sclerosis. Athena licensed the drug in 1991 from SandozLtd., of Basel, Switzerland, which markets Zanaflex in 50 countries.

The NDA for Zanaflex was filed in December 1993 after Athenaconducted two late-stage clinical studies. In March 1995 the FDArejected the drug, saying the efficacy and safety data were notsufficient for approval. (See BioWorld Today, March 9, 1995, p. 1.)

Jan Wallace, vice president of regulatory and clinical affairs, saidAthena was conducting a third trial when the FDA ruled against itssubmission for Zanaflex. That study, completed several months later,was a dose-ranging trial and measured the time it took for the drug tobecome effective _ two elements missing from previous evaluations.

Efficacy and safety data from the third trial, which involved 120patients, was incorporated into the 1993 NDA _ the first marketingapplication filed by Athena.

Zanaflex is designed to reduce abnormal muscle tone and spasmswithout producing muscle weakness by stimulating the alpha2-adrenergic receptor sites in the central nervous system at spinallevels.

Wallace said Athena officials will meet with the FDA "over the nextfew weeks" to resolve the labeling and post-marketing data collectionissues. The drug is expected to be available in the U.S. by the end ofthis year.

Athena was granted orphan drug status for Zanaflex, which means ithas exclusive marketing protection in the U.S. for seven years. Thecompany also is seeking regulatory approvals for Zanaflex in Canadaand the U.K. n

-- Charles Craig

(c) 1997 American Health Consultants. All rights reserved.