People with multiple sclerosis who have antibodies to interferon will not do well on this treatment.
Interferon-beta is now first-line treatment for relapsing-remitting multiple sclerosis (MS). But not everyone responds to the drug. Some develop neutralizing antibodies to interferon and this has now been investigated by doctors in Denmark.

They followed a group of 541 patients, selected at random from all those with MS starting treatment with interferon in Denmark between 1996 and 1999. Antibody levels were measured each year. Those who were antibody negative had a substantially longer time to relapse - by 244 days - than those who were antibody positive. The yearly relapse rate was increased more than 50 per cent in the antibody positive patients.

The study suggests that the presence of neutralizing antibodies is a good way of indicating who will not respond to interferon. These patients could be offered alternative drug therapies for MS - currently glatiramer acetate or mitoxantrone.