Analyst Worries About Tysabri: "Tysabri, the multiple sclerosis treatment from Elan appears to be getting hit by the strict safety rules that accompanied the drug's reapproval by regulators, according to one analyst.

Deborah Knobelman of the research firm Piper Jaffray slashed her estimate for worldwide Tysabri sales to $21 million for this year, down from her previous $123 million expectation. According to her feedback from doctors, physicians' adoption rates of the drug were slower than she had anticipated in the U.S. because of safety concerns, reimbursement procedures and patient-monitoring requirements......