This excerpt taken from the ELN 20-F filed Mar 30, 2006.
AFFIRM Phase 3 Monotherapy Trial
The AFFIRM trial was a two-year, randomized, multi-center, placebo-controlled, double-blind study of 942 patients conducted in 99 sites worldwide, evaluating the effect of Tysabri on the progression of disability in MS at two years and the rate of clinical relapses at one and two years. Patients with relapsing forms of MS, who had experienced at least one relapse in the previous year, were randomized to receive a 300 milligram intravenous (300 mg IV) infusion of Tysabri (n= 627) or placebo (n=315) every four weeks.
At one year, there was a 66 percent relapse rate reduction in the Tysabri-treated group versus the placebo-treated group. An annualized relapse rate of 0.25 was seen with Tysabri-treated patients versus 0.74 with placebo-treated patients.
All secondary endpoints were also met. In the Tysabri-treated group, 60 percent of patients developed no new or newly enlarging T2 hyperintense lesions compared to 22 percent of placebo-treated patients. On the one-year MRI scan, 96 percent of Tysabri-treated patients had no gadolinium enhancing lesions compared to 68 percent of placebo-treated patients. The proportion of patients who remained relapse free was 76 percent in the Tysabri-treated group compared to 53 percent in the placebo-treated group.
In February 2005, we and Biogen Idec announced that the AFFIRM monotherapy trial achieved the two-year primary endpoint of slowing the progression of disability in patients with relapsing forms of MS. Tysabri treatment led to a 42 percent reduction in the risk of disability progression relative to placebo. These data also demonstrated a 67 percent reduction in the rate of clinical relapses over two years, which was sustained and consistent with the previously reported one-year results.
In April 2005, the full two-year AFFIRM monotherapy data was presented at the 57th annual American Academy of Neurology meeting. The data was published in the New England Journal of Medicine in March 2006.