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Trastuzumab deruxtecan parenteral


Infusions of trastuzumab deruxtecan.

Drugs List

  • ENHERTU 100mg powder for concentrate for soln for infusion vial
  • trastuzumab deruxtecan 100mg powder for concentrate for soln for infusion vial
  • Therapeutic Indications


    Metastatic or locally recurrent unresectable HER2 +ve breast cancer

    Treatment of adult patients with unresectable or metastatic HER2-positive breast cancer who have previously received two or more anti-HER2-based regimens.


    Whilst the doses stated below are those recommended by the manufacturer, local cancer network protocols for the relevant indication should be consulted.

    Prior to treatment, patients should have documented HER2-positive tumour status.


    5.4mg/kg once every 3 weeks (21-day cycle).

    Trastuzumab deruxtecan should be continued until disease progression or unacceptable toxicity.

    Additional Dosage Information

    Delayed or Missed Dose
    If a dose is missed it should be administered as soon as possible. The schedule of administration should be adjusted to maintain a 3 week interval between doses.

    Dose Modification
    First dose reduction: 4.4mg/kg
    Second dose reduction: 3.2mg/kg
    Further reduction required: Discontinue treatment.

    Interstitial lung disease (ILD)/pneumonitis
    Grade 1 asymptomatic ILD/pneumonitis: Interrupt treatment until resolved to grade 0. If resolved in 28 days or less, maintain dose. If resolved in more than 28 days reduce dose.
    Grade 2 symptomatic ILD/pneumonitis: Permanently discontinue treatment.

    Grade 3 (less than 1.0-0.5 x 10 to the power of 9/L: Interrupt treatment until resolved to grade 2 or less, then maintain dose.
    Grade 4 (less than 0.5 x 10 to the power of 9/L): Interrupt treatment until resolved to grade 2 or less, then reduce dose.

    Febrile neutropenia
    Absolute neutrophil count of less than 1.0 x 10 to the power of 9/L and temperature greater than 38.3 degrees celsius or a sustained temperature of 38 degrees celsius: Interrupt treatment until resolved and reduce dose.

    Left ventricular dysfunction
    Left ventricular ejection fraction (LVEF) less than 40% or absolute decrease from baseline of 20%: Interrupt treatment. Repeat LVEF assessment within 3 weeks, if LVEF confirmed as less than 40% or absolute decrease from baseline of 20% discontinue treatment.
    LVEF between 40% and 45% and decrease is between 10% and 20%: Interrupt treatment. Repeat LVEF assessment within 3 weeks, if LVEF has not recovered to within 10% from baseline discontinue treatment.
    LVEF between 40% and 45% and decrease is less than 10% from baseline: Continue treatment. Repeat LVEF assessment within 3 weeks.
    LVEF greater than 45%: Continue treatment.
    Symptomatic congestive heart failure: Discontinue treatment.


    The initial dose should be given as a 90-minute intravenous infusion. If the initial dose is well tolerated, subsequent infusions may be administered as 30-minute intravenous infusions.


    Children under 18 years

    Precautions and Warnings

    Females of childbearing potential
    Patients over 75 years
    History of pneumonitis
    Left ventricular ejection fraction value of 50% or less
    Moderate renal impairment
    Serum bilirubin above 1.5 times upper limit of normal

    Advise ability to drive/operate machinery may be affected by side effects
    Treatment to be initiated and supervised by a specialist
    Different preparations of trastuzumab are not interchangeable
    Consult local policy on the safe use of anti-cancer drugs
    Record name and batch number of administered product
    Reduce infusion rate if mild to moderate infusion reaction occurs
    Staff: Not to be handled by pregnant staff
    Suspend treatment or reduce rate until infusion reactions resolve
    Blood counts should be performed before and periodically during treatment
    Exclude pregnancy prior to initiation of treatment
    HER2 testing is mandatory prior to initiation of therapy
    Monitor cardiac function before and regularly during treatment
    Monitor for signs and symptoms of interstitial lung disease
    Monitor for signs and symptoms of pneumonitis
    Monitor patient for infusion-associated reactions (IARs)
    Advise patient to report any symptoms of interstitial lung disease
    Discontinue treatment if interstitial lung disease develops
    Advise patient to seek advice at first indications of pregnancy
    Discontinue if treatment related pneumonitis is diagnosed
    Discontinue or review if symptoms of congestive heart failure occur
    Discontinue permanently if life threatening infusion reactions occur
    Interrupt therapy if neutrophil count <1.0x10 to the power 9/L
    Male: May cause infertility
    Female: Contraception required during and for 7 months after treatment
    Male: Contraception required during and for 4 months after treatment
    Breastfeeding: Do not breastfeed during & for 7 months after treatment
    Advise patient to report signs / symptoms of infusion related reactions

    In order to prevent medication errors it is important to be aware that trastuzumab deruxtecan should not be confused with trastuzumab or trastuzumab emtansine.

    A higher incidence of Grade 1 and 2 ILD has been observed in patients with moderate renal impairment. Patients with moderate or severe renal impairment should be monitored carefully.

    Pregnancy and Lactation


    Trastuzumab deruxtecan is contraindicated during pregnancy.

    The manufacturer does not recommend using trastuzumab deruxtecan during pregnancy. Women who become pregnant should be advised of the possibility of harm to the foetus. There is no data for the use of trastuzumab deruxtecan in pregnant women.

    Cases of oligohydramnios, some associated with fatal pulmonary hypoplasia of the foetus, have been reported in pregnant women receiving trastuzumab.


    Trastuzumab deruxtecan is contraindicated during breastfeeding.

    The manufacturer recommends that the patient either discontinues trastuzumab deruxtecan or discontinues breastfeeding during treatment and for 7 months after the last dose.

    It is not known if trastuzumab deruxtecan is excreted in human milk, however human IgG1 is secreted into human milk, and therefore the potential harm to the infant is unknown.

    Side Effects

    Abdominal pain
    Alanine aminotransferase increased
    Aphthous ulcers
    Aspartate aminotransferase increased
    Cardiac failure
    Decrease in haemoglobin
    Decreased appetite
    Decreased ejection fraction
    Dry eyes
    Febrile neutropenia
    Gastro-intestinal pain
    Hypersensitivity reactions
    Increased susceptibility to infection
    Influenza-like syndrome
    Infusion related reaction
    Interstitial lung disease
    Maculopapular rash
    Mouth ulcers
    Oral mucosal blistering
    Pustular rash
    Reduced neutrophil count
    Respiratory failure
    Sinus headache
    Skin reactions
    Upper respiratory tract infection


    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 2021

    Reference Sources

    Summary of Product Characteristics: Enhertu 100mg powder for concentrate for solution for infusion. Daiichi Sankyo UK Limited. Revised February 2021.

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    Medscape UK | Univadis prescription drug monographs & interactions are based on FDB Multilex Content

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    FDB Disclaimer : FDB Multilex is intended for the use of healthcare professionals and is provided on the basis that the healthcare professionals will retain FULL and SOLE responsibility for deciding what treatment to prescribe or dispense for any particular patient or circumstance.