What is interferon beta-1b (Betaseron, Extavia), and how is it used?
Betaseron (interferon beta-1b) is indicated for the treatment of relapsing forms of multiple sclerosis to reduce the frequency of clinical exacerbations. Patients with multiple sclerosis in whom efficacy has been demonstrated include patients who have experienced a first clinical episode and have MRI features consistent with multiple sclerosis
What are the side effects of interferon beta-1b (Betaseron, Extavia)?
Betaseron may cause serious side effects. Call your healthcare provider right away if you have any of the serious side effects of Betaseron including:
Heart problems
Betaseron may worsen heart problems including congestive heart failure. Symptoms of heart problems may include:
- swollen ankles
- shortness of breath
- not being able to lay flat in bed
- tightness in chest
- decreased ability to exercise
- fast heartbeat
- increased need to urinate at night
- injection site problems.
Skin reactions
Serious skin reactions can happen in some people including areas of severe damage to skin and the tissue below the skin (necrosis). These reactions can happen anywhere you inject Betaseron.
Symptoms of injection site problems may include:
- swelling,
- redness, or
- pain at the injection site,
- fluid drainage from the injection site, and
- breaks in your skin or
- blue-black skin discoloration.
Flu-like symptoms
Betaseron can cause flu-like symptoms including:
- fever
- tiredness
- sweating
- chills
- muscle aches when you first start to use it
These symptoms may decrease over time. Taking medicines for fever and pain relief on the days you are using Betaseron may help decrease these symptoms.
Seizures
Some people have had seizures while taking Betaseron, including people who have never had seizures before. It is not known if the seizures were related to their MS, to Betaseron, or to a combination of both.
If you have a seizure after taking Betaseron call your healthcare provider right away. The most common side effects of Betaseron include:
- low white blood cell count
- increases in your liver enzymes
- problems sleeping
- headache
- increases in your muscle tension
- weakness
- pain
- rash
- stomach pain
Tell your healthcare provider if you have any side effect that bothers you or that does not go away. These are not all the possible side effects of Betaseron. For more information, ask your healthcare provider or pharmacist. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
What is the dosage for interferon beta-1b (Betaseron, Extavia)?
The recommended starting dose is 0.0625 mg (0.25 mL) subcutaneously every other day, with dose increases over a six-week period to the recommended dose of 0.25 mg (1 mL) every other day.
If a dose of Betaseron is missed, then it should be taken as soon as the patient remembers or is able to take it. The patient should not take Betaseron on two consecutive days. The next injection should be taken about 48 hours (two days) after that dose. If the patient accidentally takes more than their prescribed dose, or takes it on two consecutive days, they should be instructed to call their healthcare provider immediately.
What drugs interact with interferon beta-1b (Betaseron, Extavia)?
Tell your healthcare provider about all the medicines you take, including prescription and nonprescription medicines, vitamins, and herbal supplements. Know the medicines you take. Keep a list of them to show your healthcare provider and pharmacist when you get a new medicine.
Do not take Betaseron if:
- you are allergic to interferon beta-1b,
- to another interferon beta,
- to human albumin, or
- mannitol.
Is interferon beta-1b (Betaseron, Extavia) safe to use while pregnant or breastfeeding?
Pregnancy
Pregnancy Category C: There are no adequate and well-controlled studies in pregnant women; however, spontaneous abortions while on treatment were reported in four patients participating in the Betaseron RRMS clinical trial. Betaseron should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.
When Betaseron (doses ranging from 0.028 to 0.42 mg/kg/day) was administered to pregnant rhesus monkeys throughout the period of organogenesis (gestation days 20 to 70), a dose-related abortifacient effect was observed. The low-effect dose is approximately 3 times the recommended human dose of 0.25 mg on a body surface area (mg/m2 ) basis. A no-effect dose for embryo-fetal developmental toxicity in rhesus monkeys was not established.
Nursing Mothers
It is not known whether Betaseron is excreted in human milk. Because many drugs are excreted in human milk and because of the potential for serious adverse reactions in nursing infants from Betaseron, a decision should be made to either discontinue nursing or discontinue the drug, taking into account the importance of drug to the mother.
What else should I know about interferon beta-1b (Betaseron, Extavia)?
How does interferon beta-1b (Betaseron, Extavia) work?
The mechanism of action of Betaseron (interferon beta-1b) in patients with multiple sclerosis is unknown.
Interferons (IFNs) are a family of naturally occurring proteins, produced by eukaryotic cells in response to viral infection and other biologic agents. Three major types of interferons have been defined: type 1 (IFN-alpha, beta, epsilon, kappa and omega), type II (IFN–gamma) and type III (IFN-lambda). Interferon-beta is a member of the type I subset of interferons. The type I interferons have considerably overlapping but also distinct biologic activities. The bioactivities of all IFNs, including IFN-beta, are induced via their binding to specific receptors on the membranes of human cells. Differences in the bioactivities induced by the three major subtypes of IFNs likely reflect differences in the signal transduction pathways induced by signaling through their cognate receptors.
Interferon beta-1b receptor binding induces the expression of proteins that are responsible for the pleiotropic bioactivities of interferon beta-1b. A number of these proteins (including neopterin, β 2-microglobulin, MxA protein, and IL-10) have been measured in blood fractions from Betaseron-treated patients and Betaseron-treated healthy volunteers. Immunomodulatory effects of interferon beta-1b include the enhancement of suppressor T cell activity, reduction of proinflammatory cytokine production, down-regulation of antigen presentation, and inhibition of lymphocyte trafficking into the central nervous system. It is not known if these effects play an important role in the observed clinical activity of Betaseron in multiple sclerosis (MS).