As mentioned in my last BNET Pharma
posting, Biogen Idec’s key multiple sclerosis drug Tysabri had been
linked to 23 worldwide cases of a potentially deadly brain infection
called progressive multifocal leukoencephalopathy, or PML — with most
confirmed cases centered in Europe, in particular Germany. Could there
be a link between the seemingly higher prevalence of Tysabri-related PML
cases in Germany and lack of oversight?
Hard and
fast data confirms that from July 2006 (when Tysabri marketing resumed)
to September 8, 2009, thirteen worldwide cases of Tysabri-related PML
occurred in patients being treated for MS with Tysabri monotherapy. Of
these, only four cases were patients in the United States, according to
an FDA Post-marketing Drug Safety report.
Germany is an
important MS market for Biogen. Aside from the U.S., Europe is home to
four of the top seven markets — Germany, Italy, UK, and Spain — in terms
of commercial dollars spent on disease modifying drugs for use in MS,
according to an analysis of the global MS market by the pharmaceutical
research outfit Visiongain.
Patients receiving monthly
Tysabri infusions in the U.S. must be enrolled in the TOUCH Distribution
Program overseen by Biogen, which involves (i) extensive monitoring of
all patients for signs of PML and (ii) education of all patients and
providers, with strong emphasis communicated to all parties that the
drug is contraindicated for use in MS patients taking any drugs that may
increase their risk of opportunistic infections, including drugs that
lower immune function (e.g., azathioprine, chemotherapy, cyclosporine)
or immunomodulators, such as the interferon-based disease-modifying
therapies.
Aside from voluntarily enrollment of
patients in Biogen’s Phase 4 trial, TYGRIS (Tysabri Global Observation
Program in Safety), which is a prospective 5-year, 5000-patient cohort
observational study to further evaluate PML risk and overall safety of
Tysabri therapy, there are few — if any — restricted distribution
programs in place throughout Europe.
As mentioned, most
of the other reported cases of PML are alleged to have occurred in
Germany, where oversight is purportedly lax, especially in the
monitoring of the presence of latent JC virus and a mandated prior
“washout” phase required in patients recently removed from other
immunosuppressant therapies, both high-risk factors for development of
PML.
However, since late summer, German authorities
have been working with the company to make sure “appropriate use of
Tysabri is monitored and followed up with [patients],” Chief Executive
Jim Mullen said on the third-quarter earnings call.
The
duration of therapy in the newly diagnosed PML patients is unknown.
That said, lax supervision in German — and other European — MS treatment
facilities could be a contributing risk factor behind the higher
incidence(s) and prevalence of reported PML cases.
In
the last 12 months, Biogen has engineered relationships between academic
reference centers and many of the larger MS clinics in Germany so that
the prescribing of Tysabri can occur in a more structured environment —
in compliance with a common protocol developed and published by the
Medical Advisory Board of German MS, according to chief operating
officer Robert Hamm. To date, 250 top German MS treatment centers are
linked to 40 reference centers, he said on the call. This initiative
should play out in the company’s favor as European regulators re-assess
the risk-benefit profile of Tysabri.
View full post here: http://industry.bnet.com/pharma/10005010/biogen-idecs-tysabri-problems-may-be-fault-of-european-doctors/?tag=shell;content
This story taken from MS News Today
