Biogen Idec Issues Avonex Warning
Firm tells doctors MS drug may cause liver damage, failureMar 17, 2005 | Boston Globe Biogen Idec Inc., already reeling from its recent decision to take its multiple sclerosis drug Tysabri off the market, yesterday sent a warning to doctors saying its big-selling MS drug Avonex can cause liver damage and liver failure.
he warning, contained in a letter posted on the Food and Drug Administration's website, sent Biogen Idec's shares plummeting, before they partially recovered to close at $37.19 for a decline of 88 cents, or 2.3 percent.
The so-called Dear Doctor letter contains the heading, ''Important Drug Warning," and says, ''In post-marketing experience, severe hepatic injury, including cases of hepatic failure, has been reported rarely in patients taking Avonex."
A Biogen Idec spokeswoman characterized the warning as an ordinary change made to the drug's packaging. Package inserts are frequently updated based on new clinical observations and the FDA's evolving priorities, she said. Liver complications are associated with all of the beta interferon drugs, a class that includes Avonex.
''The FDA sees data from all the beta interferons," said Amy Ryan, the Biogen Idec spokeswoman. ''They're seeing increased hepatic injury and failure with all three products," she said, referring to Serono SA's Rebif and Berlex's Betaseron.
Ryan said Biogen Idec noticed an increased incidence of liver injury and liver failure and initiated talks with the FDA about modifying its prescribing guide ''a few months ago." She said the interest in liver complications was a current concern of the FDA.
FDA officials could not be reached.
Biogen Idec has been hard-hit since the company said Feb. 28 it was pulling Tysabri off the market and halting clinical trials involving the drug. Two patients taking Tysabri in combination with Avonex came down with a rare, often fatal brain disease most often seen in patients with compromised immune systems, such as those with AIDS. One patient has died.
The company and its partner in Tysabri, Elan Corp. PLC of Ireland, are studying data from thousands of patients who participated in Tysabri trials to see if any others have the brain disease and to learn if there is a connection with Tysabri. Shares in both companies plunged, because Tysabri was widely expected to become a blockbuster with more than $1 billion in annual sales, split between the two firms. The companies were also conducting trials of Tysabri for additional diseases, including rheumatoid arthritis and Crohn's disease. Those programs also have been halted and their prospects are uncertain as the companies search for possible links between Tysabri and the rare disease.
Justified or not, fears that Biogen Idec's Avonex cash cow could lose ground to competitors spooked investors. With sales of Tysabri delayed for months and doubt as to whether the drug will ever return investors are counting on Avonex more than ever. Biogen grew into a biotech powerhouse largely on Avonex sales, which topped $1.4 billion last year.
Biogen's 2003 merger with Idec Pharmaceuticals propelled it into third place among US biotech firms.
Adam Walsh, an analyst at Jefferies & Co. in San Francisco, dismissed yesterday's sharp reaction to the revised Avonex label as ''noise."
''This is a knee-jerk reaction by the investing community that is hypersensitive to any negative news on Biogen Idec," he said. ''I would not expect this to have a material affect on Avonex sales. Multiple sclerosis is a debilitating disease and there's still an unmet medical need. The risk-reward ratio for patients taking the drug is still compelling."
Still, he estimated there's only a 25 percent likelihood that Tysabri will return to the market.
Yesterday, the FDA halted GlaxoSmithKline's clinical trial of an experimental multiple sclerosis drug that is similar to Tysabri. A company spokesman said the halt was a ''precautionary measure."
Glaxo, Europe's largest drug maker, hadn't expected to seek approval of its drug before 2008.
Earlier in the day, Biogen Idec chief executive James Mullen sounded a positive note at an investment conference in Boston. He said the company continued to produce Tysabri in anticipation the drug will soon be back on the market.