Why are eyes tightly shut to considering causes other than autoimmunity?
BMJ 2003;326:1213 (31 May)
Abhijit Chaudhuri, Peter O Behan
University of Glasgow Department of Neurology, Institute of Neurological Sciences, South Glasgow University Hospitals NHS Trust, Glasgow G51 4TF
Letter to Editor
We agree with Sudlow and Counsell that the evidence for the risk sharing
scheme for interferon beta and glatiramer in multiple sclerosis is poor.1
There are serious clinical and scientific flaws in advocating immunological
treatments for multiple sclerosis.2 Before committing precious resources
to any trial involving several thousand patients as proposed1 we have to
be clear about the primary end point. In our view, it can only be the prevention
of long term disability rather than reduction of short term fluctuations
related to relapses.
Progressive neurological disability in multiple sclerosis is due to neuronal loss. Widespread axonal damage is always present even at the earliest clinical stages of the disease and is independent of the inflammatory changes.3 Multiple sclerosis is not an autoimmune disease and experience has shown that azathioprine is not effective. Investing in a long term randomised trial of "interferon beta or glatiramer versus azathioprine versus no treatment" will be as wasteful as the current risk sharing scheme.1 This is for several reasons, not the least being the characteristic side effect profiles of the individual treatments that will limit effective double blinding, a fact recognised in the Cochrane review of the interferon beta trials.
Future treatment trials should be based on metabolic strategy and neuroprotection.2 3 Rather than looking for small effects in a large trial, an alternative, which historically has proved more effective, will be to invest in small trials of many treatments looking for large effects.4 Why are we keeping our eyes so tightly shut in not looking for treatment for multiple sclerosis beyond autoimmunity?
AC is supported by the Barclay Research Trust in the University of Glasgow.
© 2003 BMJ Publishing Group Ltd