Interferon beneficial for patients with suspected MS
Scott Camazine/Science Photo Library
MS less likely to develop at three years if patients are treated
early with interferon |
Patients given interferon after a neurological episode suggestive of multiple sclerosis (MS) are less likely to develop clinically definite MS than those given placebo, a three-year follow-up study has shown
(Lancet 2007;370:389).
Researchers initially randomised patients with a first event suggestive
of MS and at least two “clinically silent lesions” to receive
either interferon beta-1b or placebo every other day for two years, after
which patients were offered open-label interferon treatment. Three years
after the initial randomisation, patients given early interferon were
compared with those who started treatment after two years or after MS
diagnosis.
The researchers found that 34 per cent of patients in the early treatment
group developed clinically definite MS compared with 48 per cent in the
delayed group (absolute risk reduction 14 per cent; P=0.0011). Patients
given interferon early were also at a reduced risk of confirmed “expanded
disability status scale” (EDSS) progression than those in the delayed
treatment group (absolute risk reduction 8 per cent; P=0.022). The researchers
calculated that 12 patients would need to be treated early to avoid a
single confirmed EDSS progression.
Nevertheless, in an accompanying editorial (ibid, p363), Sean Pittock,
of the Mayo Clinic College of Medicine, Rochester, Minnesota, says that
controversy still exists about who and when to treat. He highlights a
lack of significant benefit of early treatment over delaying it for patients
with limited clinical signs or symptoms (over half of participants) or
limited disease dissemination by radiographic measurement (over a quarter
of subjects).
Dr Pittock says: “[The authors] present the first evidence that
interferon beta-1b treatment has a beneficial effect on accumulation
of confirmed disability in patients with a first event suggestive of
multiple sclerosis. The results should, however, be interpreted with
care because the magnitude of benefit, although statistically significant,
is clinically small.” He suggests that the results should not be
misconstrued as evidence for a treat-all
approach.
|
The
Pharmaceutical Journal
Acrobat
Reader