Interferon beta-1a

FDA label, Biogen Inc., intramuscular, effective 2025-11-19. Full label on DailyMed

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Quoted from the FDA label. Product labels differ by manufacturer and change over time; confirm against the label for the product you are using.

Interferon beta

Dosing in kidney impairment

This label has no separate kidney-impairment dosing section. Check warnings and clinical pharmacology in the full label.

Preparation and administration

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Important Administration Instructions (All Dosage Forms) AVONEX dosage forms (prefilled syringe and prefilled autoinjector) are single-dose. See Patient's Instructions for Use for complete administration instructions. The first AVONEX injection should be performed under the supervision of an appropriately qualified healthcare professional.

If patients or caregivers are to administer AVONEX, train them in the proper intramuscular injection technique and assess their ability to inject intramuscularly to ensure the proper administration of AVONEX. Advise patients and caregivers to: Rotate injection sites with each administration to minimize the likelihood of injection site reactions, including necrosis or localized infection [see Warnings and Precautions] NOT inject into an area of the body where the skin is irritated, reddened, bruised, infected or scarred in any way Check the injection site after 2 hours for redness, swelling, or tenderness Contact their healthcare provider if they have a skin reaction and it does not clear up in a few days Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit.

A 25 gauge, 1” needle for intramuscular injection with AVONEX prefilled syringe may be substituted for the 23 gauge, 1 ¼” needle by the healthcare provider, if deemed appropriate. A 25 gauge, 5/8” needle specific to the prefilled autoinjector is supplied with the AVONEX PEN ® Administration Dose Pack. DO NOT use any other needle with the autoinjector.

Use safe disposal procedures for needles and syringes. DO NOT re-use needles, prefilled syringes, or autoinjectors. Following the administration of each titrated dose, discard any remaining product.

Contraindications

4 CONTRAINDICATIONS AVONEX is contraindicated in patients with a history of hypersensitivity to natural or recombinant interferon beta, or any other component of the formulation [see Warnings and Precautions ( 5.3 )] . The formerly available lyophilized vial formulation of AVONEX is contraindicated in patients with a history of hypersensitivity to albumin (human). History of hypersensitivity to natural or recombinant interferon beta, albumin or any other component of the formulation ( 4 )

Pregnancy and lactation

Pregnancy

8.1 Pregnancy Risk Summary Data from a large population-based cohort study, as well as other published studies over several decades, have not identified a drug-associated risk of major birth defects with the use of interferon beta products during early pregnancy. Findings regarding a potential risk for low birth weight or miscarriage with the use of interferon beta products in pregnancy have been inconsistent (see Data ). In a study in pregnant monkeys, administration of interferon beta during pregnancy resulted in an increased rate of abortion at doses greater than those used clinically ( see Data ). In the U.S.

general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively. The background risk of major birth defects and miscarriage for the indicated population is unknown. Data Human Data The majority of observational studies reporting on pregnancies exposed to interferon beta products did not identify an association between the use of interferon beta products during early pregnancy and an increased risk of major birth defects.

In a population-based cohort study conducted in Finland and Sweden, data were collected from 1996--2014 in Finland and 2005--2014 in Sweden on 2,831 pregnancy outcomes from women with MS. 797 pregnancies were in women exposed to interferon beta only. No evidence was found of an increased risk of major birth defects among women with MS exposed to interferon beta products compared to women with MS that were unexposed to any non-steroid therapy for MS (n=1,647) within the study. No increased risks were observed for miscarriages and ectopic pregnancies, though there were limitations in obtaining complete data capture for these outcomes, making the interpretation of the findings more difficult.

Two small cohort studies that examined pregnancies exposed to interferon beta products (without differentiating between subtypes of interferon beta products) suggested that a decrease in mean birth weight may be associated with interferon beta exposure during pregnancy, but this finding was not confirmed in larger observational studies. Two small studies observed an increased prevalence of miscarriage, although the finding was only statistically significant in one study. Most studies enrolled patients later in pregnancy which made it difficult to ascertain the true percentage of miscarriages.

In one small cohort study, a significantly increased risk of preterm birth following interferon beta exposure during pregnancy was observed. Animal…

For breastfeeding, also see LactMed (National Library of Medicine), which summarizes milk levels and infant effects.

Supply and cost

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