Biogen's injectable MS drug cut relapse rate by 36 percent

The company's name is displayed on a billboard near the headquarters of Biogen Idec Inc. in Cambridge, Massachusetts June 18, 2008.

(Reuters) - Biogen Idec Inc said on Wednesday its experimental multiple sclerosis drug peginterferon beta-1a reduced the annual relapse rate of patients with multiple sclerosis by 36 percent when dosed once every two weeks.

The company, which presented its results at the American Academy of Neurology's annual meeting, said the drug reduced the proportion of patients who relapsed by 39 percent compared with patients who took a placebo.

Peginterferon beta-1a, which will be marketed, if approved, under the brand name Plegridy, is an injectable drug designed to reduce the dosing schedule of standard interferon drugs such as Biogen's own Avonex, which are typically dosed at least once a week.

In addition to Avonex, Biogen makes the MS drug Tysabri, which is widely considered the most effective on the market but has been linked with a potentially deadly brain infection known as PML.

The company is also poised to launch a new MS drug, Tecfidera, a pill that many analysts believe could become the leading treatment for the disease.

The company hopes that Plegridy will provide an option for patients seeking a less frequent dosing schedule.

Biogen said the drug reduced the risk of 12-week disability progression by 38 percent compared with a placebo when given once every two weeks.

When given once every four weeks, Plegridy was also shown to be effective and met the main goals of the trial, but patients who received the drug once every two weeks responded better.

Multiple sclerosis is a chronic condition that occurs when the body's immune system mistakenly attacks and destroys the protective sheath surrounding nerve cells in the brain, optic nerve or spinal cord. Symptoms may include loss of balance, difficulty moving arms and legs, weakness, numbness and blindness.

Analysts expect the market for interferons to shrink over the next decade as newer generation products, especially pills such as Tecfidera.

(Reporting By Toni Clarke in Washington; Editing by Paul Simao)