Biogen Idec, Elan Report Two New Cases of Rare Brain Infection in Tysabri Patients

Cambridge, MA-based Biogen Idec (NASDAQ: BIIB) and Ireland’s Elan reported some serious bad news this afternoon on their multiple sclerosis drug Tysabri. Two new patients taking the drug in Europe have developed the rare and often fatal brain infection progressive multifocal leukoencephalopathy, or PML, according to a regulatory filing with the Securities and Exchange Commission.

The filing says that one patient, in Europe, developed PML after taking Tysabri by itself for about 17 months. The patient has remained stable at home and able to walk, according to the statement. The second patient, who took Tysabri for 14 months after having taken other medicines for multiple sclerosis, is currently hospitalized, according to the company.

Tysabri has a painful history with PML. The drug was pulled from the market in February 2005 after doctors discovered two cases of the rare infection, which can be deadly. The FDA allowed Tysabri back to the market in July 2006 after deciding that the benefit of the drug—the most effective yet against MS—was worth the risk. As recently as last week, Biogen and Elan reported there were no new cases of PML since Tysabri was reintroduced with a strict monitoring program, and that 31,800 patients were taking it worldwide. The drug, Biogen’s fastest-growing product, is vital to the company’s financial future, and has been estimated to generate $2.8 billion in annual sales at current prices in 2010.

Biogen’s stock dropped 19 percent on the news at 5:58 p.m. Eastern time in after-hours trading to $56.56. The company is planning to have a conference call with investors at 8:30 a.m. Eastern time tomorrow morning.

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3 responses to “Biogen Idec, Elan Report Two New Cases of Rare Brain Infection in Tysabri Patients”

  1. I am curious if Tsyabri works by combating the seemingly little known but apparent 100% correlation of MS to a specific viral infection.

    Granted this is little known (hence not yet generally accepted), but Dr. ?Chris Powers up in Alberta (UofA) apparently found a 100% correlation to a human endogenous virus ( I hope I have the nomenclature correct ).

    If this is true, and if this is the as yet not generally accepted but possibly true cause of MS, I am curious if Tsyabri has any impact upon the associated viral load from the specific infection.

    My impression is that many of the research efforts into MS treatments have not looked at possible viral causes to MS, and if Dr. Powers’ research is correct, then I think some folks need to start giving serious consideration to anti-viral strategies for treatment and hopefully curing MS, possibly by developing a genetically engineered solution to the gene damage that the specific virus is creating ( in effect a counter virus, that might repair only damaged cells / tissue )

    There is a short discussion of this towards the end of my old but short blog post on the genesis of Adherex, a cadherin cell adhesion pharma development firm that is applying cadherin chemistry to beating cancers.

    Recent results of Adherex include in a Phase 1 combo trial for advanced untreatable Melanoma, Adherex had 8 of 16 patients gain complete remission from advanced melanoma, with no remaining traces of tumors, and of the remaining 8 patients in the P1, 4 had partial remission, and 4 had stable disease. All in a P1 trial intended typically for toxicity testing. So I think Adherex is on to something by using a specific cadherin antagonist to increase the effectiveness of cancer treatments significantly.

    Towards the end of this article, is a description of Dr. Powers’ correlation of a viral infection to clinical MS.

  2. Barbara says:

    It is my understanding that both people where male not sure if the other 2 cases where males also maybe this is a factor just a though.