Interferon Beta-1A Dosage

Medically reviewed by Drugs.com. Last updated on Aug 4, 2023.

Usual Adult Dose for Multiple Sclerosis

• AVONEX(R): 30 mcg IM once a week:

TITRATION DOSE TO REDUCE THE INCIDENCE AND SEVERITY OF INFLUENZA-LIKE SYMPTOMS:
Week 1: 7.5 mcg IM once a week
Week 2: 15 mcg IM once a week
Week 3: 22.5 mcg IM once a week
Week 4+: 30 mcg IM once a week

• REBIF(R): 22 mcg or 44 mcg subcutaneously 3 times a week:

TITRATION DOSE FOR 22 MCG:
Weeks 1 to 2: 4.4 mcg subcutaneously 3 times a week
Weeks 3 to 4: 11 mcg subcutaneously 3 times a week
Weeks 5+: 22 mcg subcutaneously 3 times a week
TITRATION DOSE FOR 44 MCG:
Weeks 1 to 2: 8.8 mcg subcutaneously 3 times a week
Weeks 3 to 4: 22 mcg subcutaneously 3 times a week
Weeks 5+: 44 mcg subcutaneously 3 times a week

Use: For the treatment of patients with relapsing forms of multiple sclerosis to slow the accumulation of physical disability and decrease 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

Renal Dose Adjustments

Data not available

Liver Dose Adjustments

Rebif(R): The manufacturer recommends caution when initiating this drug in patients with active liver disease, a history of significant liver disease, alcohol abuse, or increased serum SGPT (greater than 2.5 times ULN).

Dose Adjustments

• This drug is intended for use in patients with relapsing multiple sclerosis; however, efficacy has not been demonstrated in patients with secondary progressive multiple sclerosis without continuing relapse activity. The drug should be discontinued in patients who develop chronic progressive multiple sclerosis.
• Patients receiving Rebif (R) who cannot tolerate the higher dose may remain on the lower dose (22 mcg subcutaneously 3 times per week).
• For patients receiving Avonex (R), no additional benefit has been shown by administering a dose in excess of 30 mcg.

Precautions

Safety and efficacy have not been established in patients younger than 18 years.

Consult WARNINGS section for additional precautions.

Dialysis

Data not available

Other Comments

Administration advice:

• Rebif(R) should be administered, if possible, at the same time (preferably in the late afternoon or evening) on the same 3 days (e.g., Monday, Wednesday, and Friday) at least 48 hours apart each week.
• Pretreatment with analgesics and/or antipyretics on treatment days may ameliorate the influenza-like symptoms associated with interferon beta-1a use.

Storage requirements:

• Refer to the manufacturer product information.

Reconstitution/preparation techniques:

• Refer to the manufacturer product information.

IV compatibility:

• Refer to the manufacturer product information.

General:

• A small preliminary study suggests that in patients who develop serum neutralizing antibodies to the interferon beta drug they use, switching to an alternate interferon beta preparation may not be clinically beneficial.
• The efficacy of interferon beta-1a has not been demonstrated beyond 4 years. Re-evaluation of patients at least every second year in the 4-year period after initiation of treatment has been recommended.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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