Interferon-alpha2a reduces MRI disease activity in relapsing-remitting multiple sclerosis. Norwegian Study Group on Interferon-alpha in Multiple Sclerosis.
OBJECTIVE
To evaluate the efficacy and safety of interferon-alpha2a (IFN-alpha2a) in relapsing-remitting MS (RRMS).


BACKGROUND
Several immune-modulating therapy regimens of IFN-alpha have shown varying results in MS. A recent pilot study suggested benefits from IFN-alpha2a.


METHODS
Ninety-seven patients were randomized to receive subcutaneous injections of placebo (33 patients) or 4.5 million international units (mIU) (32 patients) or 9.0 mIU (32 patients) of IFN-alpha2a three times weekly for 6 months, with a further 6 months of follow-up. Monthly gadodiamide-enhanced MRI was the primary method of evaluating efficacy.


RESULTS
IFN-alpha2a treatment resulted in fewer new MRI lesions during the treatment period (p < 0.003). The probability of no new lesions during treatment was >2.5 times higher with 9.0 mIU IFN-alpha2a than with placebo (p < 0.005). The median number of lesions at the end of treatment was lower with IFN-alpha2a treatment than with placebo (p = 0.0004), but the difference disappeared during follow-up. The total number of lesions (mean) increased by 4.78 with placebo, 0.86 with 4.5 mIU IFN-alpha2a, and 0.28 with 9.0 mIU IFN-alpha2a during treatment (p = 0.030). No treatment effect on exacerbation rate, progression of disability, or quality of life was detected. Nine patients discontinued treatment, five because of adverse events.


CONCLUSIONS
IFN-alpha2a treatment significantly reduced disease activity as measured by MRI, but the efficacy disappeared within 6 months after discontinuation of treatment. A long-term study of more patients using disability as a primary outcome measure is needed to evaluate the clinical impact.
Myhr
K M
KM
Department of Neurology, Haukeland University Hospital, University of Bergen, Norway.
Riise
T
T
Green Lilleås
F E
FE
Beiske
T G
TG
Celius
E G
EG
Edland
A
A
Jensen
D
D
Larsen
J P
JP
Nilsen
R
R
Nortvedt
M W
MW
Smievoll
A I
AI
Vedeler
C
C
Nyland
H I
HI
D000328:Adult; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D000077190:Interferon alpha-2; D016898:Interferon-alpha / Q000627:therapeutic use*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000473:pathology* / Q000628:therapy*; D011788:Quality of Life; D011994:Recombinant Proteins; D013997:Time Factors; D016896:Treatment Outcome
D000077190:Interferon alpha-2; D016898:Interferon-alpha; D011994:Recombinant Proteins