ANNOUNCER: Medications have been created to effectively curb the frequency and severity of multiple sclerosis attacks. One kind of treatment uses interferons.
ANDREW PACHNER, MD: Interferons are proteins made by your body, made as part of the immune system response to some stimulus.
ANNOUNCER: All three interferons appear to be equally effective.
ANDREW PACHNER, MD: There is no, at this point, clear evidence one way or the other. They decrease the number of active lesions, active MS areas in your MRI and the second thing that they do is they decrease the number of attacks.
KAREN BLITZ-SHABBIR, DO: The interferons, we think start to work pretty quickly. If you look at MRI, the decrease in lesion accumulation occurs in a month or two.
ANNOUNCER: Interferons do differ in their tendency to produce what's known as neutralizing antibodies.
KAREN BLITZ-SHABBIR, DO: If you develop a neutralizing antibody, you neutralize the effect of the drug; it makes it so that the drug does not work any more. We know that, with Avonex, the likelihood of developing a neutralizing antibody is very low, 5 percent. We know that, with Betaseron, the likelihood is any where between 30 and 45 percent, and, with Rebif, it's about 25 percent.
ANNOUNCER: The medications can all be self-injected, but on different schedules and in different ways.