Licensed to reduce the relapse frequency in multiple sclerosis and also for use in those with progressive MS with relapses. Patients must be able to walk, and have had at least two attacks in the previous two to three years.
Or, a single demyelinating episode with an active inflammatory process, severe enough to require IV corticosteroids in patients who are at high risk of developing MS.
Beta interferon 1b is also licensed for patients with secondary progressive MS, but its efficacy is unknown.
The initial mechanism of an acute multiple sclerosis demyelinating event is thought to be inflammatory - and therefore suppressing this process with immunomodulating drugs may be beneficial.
Beta interferon reduces the clinical relapses and new evidence of demyelination on MRI. It has also been found reduce the progression of function disability, which can be formally assessed with an EDSS (expanding disability status scale) in clinic.
Those with progressive disease and no recognisable relapses are not prescribed immunomodulating drugs. Studies have found that there is no evidence that it halts the disease in these patients. The mechanism of progressive MS may not be a wholly inflammatory one and more neurodegenerative, due to a gradual loss of axons, and this may be why these drugs are less effective.
Interferon - beta is a class 1 interferon. Its mechanism of action is not wholly clear but may be due to:
- Inhibiting the proliferation of T cells
- Downregulating expression of MHC molecules on antigen presenting sites
- Altering the balance between proinflammatory and regulatory cytokines
- Reducing the movement of inflammatory cells in the CNS
Some patients develop antibodies against beta interferon which reduces its efficacy and if they are persistently elevated on serum testing, this medication should be stopped, particularly if there is no clinical benefit.
SC or IM dependent on the preparation.
Beta-interferon appears to have no significant interactions.
Patients should have an understanding that this is a medication which is aimed to reduce relapse rate and that they may be taken off the medication if it is found to be ineffective and they no longer fit the criteria.
Beta-interferon is a naturally produced protein. It is therefore not suitable for oral administration (as it would merely be digested).
