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Peginterferon beta-1a parenteral

Updated 2 Feb 2023 | Interferon beta


Parenteral formulations of peginterferon beta-1a.

These products have been produced by recombinant technology using Chinese Hamster Ovary (CHO) cell lines.

Drugs List

  • peginterferon beta-1a 125microgram/0.5ml solution for injection pre-filled syringe
  • peginterferon beta-1a pre-filled pen 125microgram/0.5ml injection solution
  • peginterferon beta-1a pre-filled pen 63micrograms/0.5ml + 94micrograms/0.5ml injection solution
  • PLEGRIDY 125microgram/0.5ml solution for injection pre-filled pen
  • PLEGRIDY 125microgram/0.5ml solution for injection pre-filled syringe
  • PLEGRIDY INITIATION PACK solution for injection pre-filled pen
  • Therapeutic Indications


    Treatment of relapsing-remitting multiple sclerosis


    Titration of the peginterferon dose may help to ease flu-like symptoms.


    Dose 1 (at day 0): 63 micrograms.
    Dose 2 (at day 14): 94 micrograms.
    Dose 3 (at day 28): 125 micrograms.
    Subsequent doses (every 14 days): 125 micrograms.

    Additional Dosage Information

    Advise patient a missed dose should be administered as soon as remembered. If it is more than 7 days till the next scheduled dose continue the dose regime as scheduled. If it is less than 7 days till the next scheduled dose patients should administer a dose and begin a new 2 week dosing schedule.


    Patients should be advised to rotate sites for subcutaneous or intramuscular injections every two weeks.
    Pre-filled pen
    For subcutaneous injection.

    Pre-filled syringe
    For intramuscular injection.


    Children under 18 years
    Suicidal ideation
    Severe depression

    Precautions and Warnings

    Cardiac arrhythmias
    Congestive cardiac failure
    Coronary arteriosclerosis
    Epileptic disorder
    History of depression
    History of seizures
    Severe cardiac disorder
    Severe hepatic impairment
    Severe renal impairment
    Thyroid dysfunction

    Treatment to be initiated and supervised by a specialist
    Advise patient to report injection site reactions where the skin breaks
    Record name and batch number of administered product
    Use only if the solution is clear and colourless
    Monitor full blood count and differential WBC before and during therapy
    Monitor hepatic function before treatment and regularly during treatment
    Monitor cardiac function in patients with cardiac disease
    Monitor closely patient with depression
    Monitor for signs of nephrotic syndrome
    Monitor renal function regularly
    Monitor serum biochemistry regularly
    Monitor thyroid function regularly if history of dysfunction
    Monitor thyroid function where clinically indicated
    Review self injection technique periodically, especially if reactions occur
    Advise patient to report any new or worsening depression/suicidal ideation
    Advise patient to report symptoms of thrombotic microangiopathy
    Advise patient to stop therapy & contact Dr if hypersensitivity signs occur
    Consider discontinuing treatment if nephrotic syndrome occurs
    Discontinue if severe hypersensitivity reactions occur
    Discontinue if thrombotic microangiopathy is confirmed
    Female: Ensure adequate contraception during treatment

    Cases of thrombotic microangiopathy (TMA) may manifest as thrombocytopenia purpura or haemolytic uraemic syndrome. Early symptoms include thrombocytopenia, new onset hypertension, fever and central nervous system symptoms. If such symptoms develop testing of blood platelet levels, serum LDH, blood films and renal function should be carried out.

    Analgesics and antipyretics may be used prophylactically or concurrent to manage any flu-like symptoms.

    Consider discontinuing peginterferon beta-1a following a single site of necrosis depending on the extent of necrosis.

    In addition to normal laboratory tests required for monitoring patients with multiple sclerosis, complete blood chemistries, including liver function tests, blood cell and platelet counts should be performed prior to initiation of peginterferon beta-1a therapy, at regular intervals during and periodically thereafter.

    Not all presentations are suitable for all routes of administration.

    Pregnancy and Lactation


    Use peginterferon beta-1a with caution during pregnancy.

    The manufacturer states that the use of interferon beta-1a during pregnancy may be considered if clinically required. Human data suggests no increased risk of major congenital abnormalities during the first trimester due to peginterferon beta-1a. Experience during the second than third trimester is very limited.

    Animal studies have shown peginterferon beta may possibly increase the risk of spontaneous abortion and low birth weight when administered in the first trimester. The risk of spontaneous abortions in pregnant women exposed to interferon beta cannot be evaluated based on the currently available data, but does not currently suggest an increase.


    Peginterferon beta-1a is considered safe for use during breastfeeding.

    The manufacturer states that peginterferon beta-1a can be used during breastfeeding. It is suggested that the levels of interferon beta-1a secreted into human breast milk is negligible.

    Schaefer suggests that due to the large molecular weight of peginterferon beta it is not excreted into human milk.

    LactMed reported no adverse effects in partially breastfed infants when breastfeeding mothers received peginterferon beta-1a. Therefore, no special precautions appear to be necessary while using peginterferon beta-1a.

    Side Effects

    Decrease in haemoglobin
    Gamma glutamyl transferase (GGT) increased
    Haemolytic uraemic syndrome
    Hypersensitivity reactions
    Increase in ALT level
    Increase in AST level
    Influenza-like syndrome
    Injection site reactions
    Necrosis (injection site)
    Nephrotic syndrome
    Pain on injection
    Pulmonary artery hypertension
    Reduced platelet count
    Rise in body temperature
    Thrombotic microangiopathy
    Thrombotic thrombocytopenic purpura
    White blood cell count decreased


    It is strongly recommended that the UK National Poisons Information Service be consulted on cases of suspected or actual overdose where there is doubt over the degree of risk or about appropriate management.

    The following number will direct the caller to the relevant local centre (0844) 892 0111

    Information may be obtained if you have access to ToxBase the primary clinical toxicology database of the National Poisons Information Service. This is available via password on the internet ( ) or if this is unavailable at the backup site ( ).

    Further Information

    Last Full Review Date: May 2019

    Reference Sources

    Drugs During Pregnancy and Lactation: Treatment Options and Risk Assessment, 3rd edition (2015) ed. Schaefer, C., Peters, P. and Miller, R. Elsevier, London.

    Summary of Product Characteristics: Plegridy 63, 94 and 125 micrograms solution for injection in pre-filled pen. Biogen Idec Ltd. Revised December 2020.

    US National Library of Medicine. Toxicology Data Network. Drugs and Lactation Database (LactMed).
    Available at:
    Peginterferon Beta. Last revised: 15 June 2020
    Last accessed: 13 April 2021

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