Making Sense of MS Research

Summaries of independent,
high-quality research about multiple sclerosis treatments

Interferons for Primary Progressive MS

Detailed answer

Disability

Interferons do not appear to have any effect on the chance of disability getting worse over two years.

In words

  • Without interferons 37 per 100 people would experience worsening disability over two years and 63 would not.
  • With interferons 33 per 100 people would experience worsening disability over two years and 67 would not.
  • Therefore with interferons 4 fewer people per 100 would experience worsening disability over two years compared to without interferon.

In pictures

Without interferons, 37 per 100 people with MS are estimated to have worsening disability
Graph showing 37 per 100 people with MS are estimated to have worsening disability.
1 100 Graph showing 33 per 100 people with MS are estimated to have worsening disability.
With interferons, 33 per 100 people with MS are estimated to have worsening disability

In technical terms, the result was not statistically significant, the confidence intervals crossed 1 and the boundaries were wide. This means there is statistical uncertainty about the effect and it could have occurred by chance alone.

Do these results look different from what you’ve read elsewhere? See the FAQ page for an explanation. You can also discuss the results with your local MS Australia office.

Side effects

Interferons are generally well tolerated.  Most interferon side effects are mild and can often be relieved with symptomatic treatments, without the need to stop taking them.

●●●
Very common (10-100 per 100)
●●
Common (1-9 per 100)
Uncommon (less than 1 per 100)
?
There is no information about the side effect
Symptoms
Avonex® Betaferon® Rebif®
Flu-like symptoms
(fever, chills, cough, sore throat, flu-like symptoms)
●●● ●●● ●●●
Headache ●●● ●●● ●●●
Pain and redness at the injection site ●● ●●● ●●●
Muscle weakness ●● ●●● ●●
Itching, rash ●● ●●
Nausea, vomiting and diarrhoea ●● ●●
Depressed mood, insomnia ●● ●●
Joint pain ●● ? ●●
Skin break down at the injection site ? ●●
Weight loss ●● ? ?
Hair loss
High blood pressure ? ?
Blood test values
Avonex® Betaferon® Rebif®
Low white blood cell counts ●● ●●●
Low red blood cell counts ●● ●●●
Low blood platelet counts ●●●
Abnormal liver enzyme levels ? ●●●
Abnormal thyroid hormones ? ?

Sources: This side effect data has been collated by the IN-DEEP project team using publically available data from the European Medicines Agency, Micromedex and the studies included in Cochrane reviews on Interferons.

What we don’t know from the results of this review

In this review there was no information about the effect of interferons on quality of life in people with primary progressive MS.  Because the studies in this review only went for two years we don’t know the effect of interferons on primary progressive MS in the longer term.  This review did not draw any conclusions about whether there was any difference between the effect of the three different interferons (Avonex®, Betaferon® and Rebif®).

What about the quality of the included studies?

Overall, the quality of these results is low.  The studies were randomised controlled trials, which are considered the most rigorous study design that minimises the risk of misleading results.  However, there were only two studies, with a total of 123 participants included in the review.  To be more certain about the effect of interferons in PPMS we need more studies.

The really detailed answer

For more information, or to read about the individual studies included in this review, you can access the Cochrane review on which this treatment summary is based: