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FDA Lets MS Drug Tysabri Return

Strict Rules Focus on Rare, Potentially Deadly Brain Infection

About Tysabri

Tysabri is a monoclonal antibody given usually once a month by health care professionals. It’s used to treat patients with relapsing forms of MS in order to reduce the frequency of flare-ups.

The new rules mean that before taking Tysabri, patients must enroll in a risk-minimization program designed by Biogen-Idec. Patients also need to get a brain scan using magnetic resonance imaging (MRI) before taking Tysabri.

Doctors who prescribe Tysabri, pharmacies that dispense the drug, and infusion sites that administer the drug must also enroll in the risk-minimization program.

Tysabri shouldn’t be used in combination with other immune-system modifying drugs. It’s intended for patients who have not responded adequately to -- or cannot tolerate -- other treatments for MS, states the FDA. However, other uses of Tysabri aren’t forbidden on the label.

Risk-Minimization Plan

In February 2005, after Biogen-Idec took Tysabri off the market, the FDA put Tysabri’s clinical trials on hold.

A year later, the FDA let a Tysabri clinical trial resume after a re-examination of patients in Tysabri’s previous clinical trials confirmed no additional cases of PML.

In March 2006, the FDA consulted its Peripheral and Central Nervous Systems Drugs Advisory Committee about ways to cut the risk of PML while making Tysabri available to appropriate patients.

The committee recommended a risk-minimization program with mandatory patient registration and periodic follow-up for Tysabri. The newly approved plan is the result. It’s designed to identify any PML cases as quickly as possible and to learn more about which patients may be at higher risk.

The plan’s rules include:

  • Tysabri will only be prescribed, distributed, and infused by prescribers, infusion centers, and pharmacies registered with the program.
  • Tysabri will only be administered to patients who are enrolled in the program.
  • Before starting Tysabri, patients must get magnetic resonance imaging (MRI) to help differentiate future MS symptoms from PML.
  • Patients on Tysabri are to be evaluated at 3 and 6 months after the first infusion and every 6 months after that, and their status will be reported regularly to Biogen Idec.

Additional information on the TOUCH Prescribing Program is available from the companies by calling 1-800-456-2255.


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