Wait for further evidence confirming effect of interferon beta in multiple sclerosisBMJ 1997; 314 doi: https://doi.org/10.1136/bmj.314.7096.1763 (Published 14 June 1997) Cite this as: BMJ 1997;314:1763
- Richard Hughes, Professor of neurologya
Editor—The debate about the value of interferon beta in multiple sclerosis will continue until there is sufficient evidence to settle the question beyond doubt. The authors of the various letters in the BMJ have largely adopted debating positions that reflect their acknowledged conflicts of interest.1 I acknowledge my own conflict of interest but wish to reiterate concerns about conflicts of evidence.2 3
Briefly, subcutaneous interferon beta causes side effects that prevented adequate blinding of patients and may have contributed to the reporting of fewer relapses in patients treated with interferon beta-lb than with placebo. The reduction in lesion load on T2 weighted magnetic resonance imaging after two and three years that was seen with interferon beta-lb was not confirmed with interferon beta-la. The reduction in the development of disability with interferon beta-1a was measured with the lower part of the Kurtzke expanded disability status scale, which reflects impairment rather than disability, and was not observed with interferon beta-lb.
Peter Cardy has as much right as any neurologist to point out the devastating effect that relapses may have in some patients.1 As he pointed out in his earlier letter, however, we do not have information on the relative value that patients place on reducing relapses compared with slowing progression of disability.4 The compassion and humanity for which Peter Cardy appeals may be better served by our waiting a few more months to find out whether the promising results with these interferons can be replicated. Premature adoption of interferon beta risks obscuring the truth and causing patients to inject themselves with a drug that certainly has side effects but does not certainly offer long term benefits. Patients with multiple sclerosis, their neurologists, and pharmaceutical companies will be able to argue much more powerfully for provision of the drug if the evidence can be confirmed.
*Richard Hughes is participating in trials of interferon beta-1a in multiple sclerosis funded by Ares Serono.