3xs a week subcutaneous (under the skin) injection
Weekly; intramuscular (into the muscle) injection
Every other day; subcutaneous (under the
skin) injection
Common Side Effects
Injection site reactions. Rarer: a reaction immediately after
injection which includes anxiety, chest tightness, shortness of breath and flushing. This
lasts 15-30 minutes and has no known long-term effects.
Common side effects include flu-like symptoms (fatigue, chills, fever,
muscle aches, and sweating) and injection site reactions (swelling, redness, discoloration,
and pain) and depression.
Flu symptoms following injection, which lessen over time for many
people. (See over for how to manage.) Rarer: mild anemia, elevated liver enzymes.
Flu symptoms following injection, which lessen over time for many.
(See over for how to manage.) Injection site reactions, about 5% of which need medical
attention. Rarer: elevated liver enzymes, low white blood cell counts.
Patient Information and Financial Support Programs
Differential effects of three interferon betas on
neutralising antibodies in patients with multiple sclerosis: a follow up study
in an independent laboratory.
Bertolotto A, Malucchi S, Sala A, Orefice G, Carrieri PB, Capobianco M,
Milano E, Melis F, Giordana MT.
Centro di Riferimento Regionale Sclerosi Multipla & Laboratorio di Neurobiologia
Clinica, Divisione Universitaria di Neurologia, Azienda Ospedaliera S Luigi,
Universita di Torino, Orbassano, Italy. nsglb@tin.it
OBJECTIVE: To evaluate the incidence and the prevalence of neutralising
antibodies (NABs) to three interferon beta (IFNbeta) products in patients with
multiple sclerosis (MS). METHODS: Sera were tested from 125 patients with
relapsing-remitting MS. Patients were treated with IFNbeta-1b (Betaferon, n =
29) 8 MIU subcutaneously every other day, IFNbeta-1a (Avonex, n = 44) 30 microg
intramuscularly once weekly, or IFNbeta-1a (Rebif, n = 36) 22 microg
subcutaneously three times weekly for 6 to 18 months. An additional 16 patients
were treated with Rebif 22 microg intramuscularly once or twice weekly. NABs
were assessed using the cytopathic effect assay before treatment and every three
months during treatment. Patients with two or more consecutive positive samples
were considered to be persistent NAB positive (NAB+). RESULTS: At baseline, no
patients were NAB+. NABs developed during the first three months of treatment
and continued to develop until month 18. Over 18 months of treatment, the risk
of being persistent NAB+ was 31% for Betaferon, 15% for Rebif, and 2% for Avonex
(Betaferon versus Avonex, p = 0.001; Betaferon versus Rebif, p = 0.19; Rebif
versus Avonex, p = 0.04). In all patients with one or more NAB+ samples, the
risk of becoming NAB+ was 38% for Betaferon, 18% for Rebif, and 7% for Avonex (Betaferon
versus Avonex, p = 0.0007; Betaferon versus Rebif, p = 0.10; Rebif versus Avonex,
p = 0.07). At month 18, the prevalence of persistent NAB+ patients was 31.6% for
Betaferon, 18.7% for Rebif, and 4% for Avonex. Numbers of NAB+ patients observed
were similar with intramuscular Rebif and with subcutaneous Rebif. CONCLUSION:
The three IFNbeta preparations have different degrees of immunogenicity, with
Betaferon producing the highest incidence of NABs and Avonex the lowest. These
differences should be considered by neurologists when selecting treatment for
their patients with MS because NABs can reduce both bioavailability and clinical
efficacy of IFNbeta.
