Elan's share price fell more than 70% on February 28th 2005, when TYSABRI was suspended. Elan is more dependent on the return of the multiple sclerosis drug to the market than its partner Biogen Idec

Elan's multiple sclerosis drug Tysabri should return to the US market, an advisory panel from the Food and Drug Administration recommended today.

Tysabri sales were suspended on February 28, 2005 after three patients developed a serious brain and spinal cord infection and two of them died.  

The US Food and Drug Administration has been holding an advisory meeting since Monday to decide if Tysabri should return to the market and it will make a final decision at the end of the month.

Elan, and its partner US biotech firm Biogen Idec, have been seeking approval from the US Food and Drug Administration for the treatment to be sold again, with controls to quickly identify side effects. The FDA's concern is whether PML can be treated even if it is found early.

This was the second day of meetings, a large and vocal group of MS sufferers have been at the meetings saying that it's a patients right to take the medication of their choice. They say Tysabri's efficacy far outweighs its side effects.

Elan and Biogen had been running clinical trials involving 3,000 patients.

Last week, US broker Piper Jaffray's stock analyst Deborah Knobelman released results of a poll of 140 neurologists on their opinion of Tysabri. The drug had been on the US market for three months after being approved by the FDA in November 2004 until it was suspended on February 28, 2005.

Knobelman said in a research note that 59 percent of doctors surveyed said it was too soon to bring Tysabri back to the market because of limited safety data on the drug, even though 92 percent said the treatment could be a valuable therapy to some multiple sclerosis patients.

Multiple sclerosis (MS) is an incurable disease where the body's immune system attacks myelin, or the tissue that insulates nerve fibres. Tysabri clinical trials linked the drug to progressive multifocal leukoencephalopathy (PML), a rare disease found in patients with immune deficiencies where parts of the brain becomes inflamed.

Doctors said in the poll that they would use Tysabri to treat about 10 percent of multiple sclerosis patients, or when all other available treatments had failed.

Knobelman also reported that 57 percent of doctors said the risk of PML was worth using Tysabri if all other drugs failed, and that only 6 percent would use Tysabri as a first-line therapy.