February 17, 2011
By Staff Reporter
The Irish firm’s share price collapsed in February after it had to suspend sales of Tysabri, a flagship new drug that it had developed in association with a Cambridge, Mass., company, Biogen Inc.
Tysabri had initially been hailed as an exciting discovery because trials had indicated that it was more effective than any previous drug in combating the symptoms of multiple sclerosis (M.S.).
However, February brought news that one person who had taken Tysabri had died from a rare disorder of the brain and spinal cord. At the time, another patient was believed to have contracted the disease. This second case was later confirmed. A third instance of the disorder – progressive multiphocal leukoencephalopathy, or PML – was discovered in March.
Last week, just when it seemed like Elan’s fortunes were on the upswing again, the Boston Globe newspaper reported that Biogen had told the Food And Drug Administration that a fourth patient who had taken Tysabri may have contracted PML.
At one point last Thursday, Elan’s shares in Dublin plummeted to EURO4.60, having closed the previous evening at EURO6.30. The company’s share price was just over EURO20 before the Tysabri controversy first struck.
However, the shares have staged a mild comeback since it became apparent that the fourth suspected case of PML has not been confirmed. At time of going to press, Elan was trading at EURO5.30 in Dublin and $6.53 in New York.
According to the Globe, the fourth person suspected to have been afflicted by PML is a 48-year-old woman. As is the case with two of the three previously confirmed cases of PML, she was taking Tysabri in combination with Avonex, another multiple sclerosis drug sold by Biogen.
Two expert neurologists to whom the Globe showed a report about this fourth person’s symptoms suggested that PML was likely. “It sure sounds convincing to me,” one of the experts, Dr Douglas R Jeffrey, told the newspaper. Jeffrey is a neurologist at Wake Forest University School of Medicine in North Carolina.
The continuing troubles of Tysabri have come as a bitter blow to multiple sclerosis sufferers and their families. Graham Love, the chief executive of M.S. Ireland, an organization that works on behalf of people who suffer from the disease, previously told the Echo that there had at one time been a widespread belief that Tysabri could be “something of a wonder drug”. The drug’s initial results suggested that it could reduce M.S. episodes by around 66 percent.
Those impressive results were the main factor behind the FDA decision to approve Tysabri for sale after only one year of clinical trials, rather than the more usual two years. That decision has come under scrutiny in recent months.
Multiple sclerosis is a consequence of the body’s immune system going wrong. Under normal circumstances, the body’s so-called ‘T-cells’ act to fight off infections. In M.S., these T-cells behave aberrantly, attacking a healthy substance called myelin that covers nerve endings. The result is an impairment of the entire nervous system that can result in everything from numbness of limbs to paralysis. In a relatively small number of cases, sufferers develop dementia.
The idea behind Tysabri was to stop the T-cells from doing their damage. But other experts warned of obvious risks with that plan – if the action of the T-cells was impaired, would that then leave the body with weakened defenses when it came to the battle against normal infections?
That question has still not been definitively answered. Although the circumstantial evidence is extremely worrying, the drug companies have drawn attention to the fact that no link between Tysabri and PML has been proven beyond doubt.
The fourth suspected case of PML came shortly after Elan’s share price had received a fillip. The company’s CEO, Kelly Martin, told the company’s AGM in Dublin on May 26 that he was confident the drug would return to the market.
“There is still extremely high interest in the drug, and it remains the only product with the potential to halt the progression of M.S.,” Martin told the meeting.