Irish drugs firm Elan and its US partner Biogen Idec announced today the one-year anniversary of TYSABRI (natalizumab) as a treatment for relapsing forms of multiple sclerosis (MS).
One year following its return to market in the US and introduction in the European Union, the companies estimate that as of mid-July 2007 in both commercial use and clinical trials approximately 14,000 patients are currently on TYSABRI therapy worldwide.
As of mid-July 2007:
- In the US, over 8,600 patients are on TYSABRI commercially and over 1,800 physicians have prescribed the therapy;
- In the EU, over 4,300 patients are on TYSABRI therapy commercially; and
- In global clinical trials, approximately 1,000 patients are on TYSABRI therapy.
Over the past year I have seen my patients benefit greatly from TYSABRI. As expected from clinical trials, TYSABRI is having a positive impact on their lives. The compelling efficacy of TYSABRI offers MS patients hope in the management of their disease, said Dr. Howard Rossman, Medical Director, MS Center, Michigan Institute for Neurological Disorders in Farmington Hills, Michigan, and Clinical Professor of Neurology at Michigan State University. Increased experience with TYSABRI will continue to inform us and contribute to our understanding of the important role of this therapy for people living with MS.
TYSABRI has had an incredible effect, and the improvements I have experienced are very real. I understand there are important risks to this therapy, but the benefits of TYSABRI were far too important for my family and me to overlook, said TYSABRI patient, Mike Lynch.
In July 2006, TYSABRI was reintroduced in the US under the TOUCH Prescribing Program, a restricted distribution program, and was also introduced in the EU under a risk management plan. These programs were developed due to the increased risk of progressive multifocal leukoencephalopathy (PML), an opportunistic viral infection of the brain that usually leads to death or severe disability.
TYSABRI is a treatment approved for relapsing forms of MS in the US and relapsing-remitting MS in the European Union. According to data that have been published in the New England Journal of Medicine, after two years, TYSABRI treatment led to a 68% relative reduction (p<0.001) in the annualized relapse rate compared to placebo and reduced the relative risk of disability progression by 42-54% (p<0.001).
TYSABRI increases the risk of PML. Other serious adverse events that have occurred in TYSABRI-treated patients included hypersensitivity reactions (e.g., anaphylaxis), infections, depression and gallstones. Serious opportunistic and other atypical infections have been observed in TYSABRI-treated patients, some of whom were receiving concurrent immunosuppressants. Herpes infections were slightly more common in patients treated with TYSABRI. In MS trials, the incidence and rate of other serious and common adverse events, including the overall incidence and rate of infections, were balanced between treatment groups. Common adverse events reported in TYSABRI-treated patients include headache, fatigue, infusion reactions, urinary tract infections, joint and limb pain, lower respiratory infections, rash, gastroenteritis, abdominal discomfort, vaginitis, and diarrhea.
TYSABRI is approved in the United States, European Union, Switzerland, Canada, Australia and Israel. TYSABRI was discovered by Elan and is co-developed with Biogen Idec.