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Romiplostim parenteral

Updated 2 Feb 2023 | Platelet disorders


Parenteral formulations of romiplostim.

This product has been produced by recombinant technology using E.coli.

Drugs List

  • NPLATE 125microgram powder for solution for injection vial
  • NPLATE 250microgram powder + solvent for solution injection syringe
  • romiplostim 125microgram powder for solution for injection vial
  • romiplostim 250microgram powder + solvent for solution injection syringe
  • Therapeutic Indications


    Idiopathic thrombocytopenic purpura


    Not all available brands are licensed for all age groups.

    Treatment should remain under the supervision of a specialist in haematological diseases.

    Actual body weight at initiation of treatment should always be used when calculating dose of romiplostim.

    In adults, future dose adjustments are based on changes in platelet count only.

    In paediatric patients, future dose adjustments are based on changes in platelet counts and changes in body weight. Reassessment of body weight is recommended every 12 weeks.


    The initial dose is 1 microgram/kg based on actual body weight (consult manufacturer information for examples). This is repeated once weekly, and adjusted by once weekly increments of 1 microgram/kg until the patient achieves a platelet count equal to or greater than 50 x 10 to the power of 9/L. Do not exceed a maximum dose of 10 micrograms/kg per week.

    Suggested dose adjustment schemes

    Patients with platelet count less than 50 x 10 to the power of 9/L
    Increase once weekly dose by 1 microgram/kg.

    Patients with platelet count greater than 150 x 10 to the power of 9/L for 2 consecutive weeks
    Decrease once weekly dose by 1 microgram/kg.

    Patients with platelet count greater than 250 x 10 to the power of 9/L
    Do not administer, continue to assess platelet count weekly. After the platelet count has fallen to below 150 x 10 to the power of 9/L, resume dosing with once weekly dose reduced by 1 microgram/kg.

    Treatment discontinuation
    Treatment with romiplostim should be discontinued if platelet count does not increase to a level sufficient to avoid clinically important bleeding after 4 weeks of romiplostim therapy at the highest weekly dose of 10 micrograms/kg.


    Children aged over 1 years
    (See Dosage; Adult)

    Additional Dosage Information

    The volume of romiplostim to administer is calculated based on body weight, dose required, and concentration of product. Consult manufacturers information for examples.

    In some patients platelet count may abruptly fall below 50 x 10 to the power of 9/L after dose reduction or treatment discontinuation. In these cases, if clinically appropriate, higher cut-off levels of platelet count for dose reduction (200 x 10 to the power of 9/L) and treatment interruption (400 x 10 to the power of 9/L) may be considered according to medical judgement.


    For subcutaneous injection only.

    Patients who have a stable platelet count of equal to or more than 50 x 10 to the power of 9/L for at least 4 weeks without dose adjustment may be eligible for self-administration of romiplostim once trained. After the first 4 weeks of self-administration, the patient should again be supervised while reconstituting and administering romiplostim. Only patients who demonstrate the ability to reconstitute and self-administer romiplostim are allowed to continue to do so.

    Self-administration of romiplostim is not allowed in paediatric patients.


    Children under 1 year

    Precautions and Warnings

    Females of childbearing potential
    Predisposition to thromboembolic disease
    Chronic hepatic disorder
    Hepatic impairment - Child-Pugh score greater than 6
    Renal impairment

    Advise ability to drive/operate machinery may be affected by side effects
    Not all available brands are licensed for all age groups
    Treatment to be initiated and supervised by a specialist
    Record name and batch number of administered product
    Blood counts should be performed before and periodically during treatment
    Initial dose should be based on actual body weight
    Perform peripheral blood smear prior to and during treatment
    Children: Monitor body weight every 12 weeks
    Investigate patients developing a sudden lack of response to treatment
    Monitor platelet counts monthly after first month of treatment
    Monitor platelets weekly until minimum 50x10 to the power of 9/L
    Thrombocytopenia likely to reoccur upon discontinuation of treatment
    Interrupt treatment if platelet count above 250x10 to the power of 9/L
    Discontinue if platelet count is insufficient after 4 weeks at max dose
    Female: Ensure adequate contraception during treatment

    Platelet counts should be assessed weekly until a stable platelet count (equal to or more than 50 x 10 to the power of 9/L for at least 4 weeks without dose adjustment) has been achieved. Platelet counts should be assessed monthly thereafter. A loss of response or failure to maintain a platelet response to romiplostim within the recommended dosing range should be investigated.

    Patients should be monitored and managed when discontinuing romiplostim. There is an increased risk of bleeding if romiplostim is discontinued in the presence of anticoagulants or antiplatelet drugs. It is recommended that ITP treatment be restarted according to current treatment guidelines if treatment with romiplostim is discontinued.

    A positive benefit/risk for romiplostim is only established for the treatment of thrombocytopenia associated with chronic immune thrombocytopenic purpura (ITP) and romiplostim must not be used in other clinical conditions associated with thrombocytopenia. Romiplostim must not be used for the treatment of thrombocytopenia due to Myelodysplastic Syndromes (MDS) or any other cause of thrombocytopenia other than ITP outside of clinical trials. In clinical trails using romiplostim in patients with MDS, there were reported cases of transient increases in blast cell counts and cases of progression to acute myeloid leukaemia.

    The diagnosis of ITP in adults and elderly patients should have been confirmed by the exclusion of other clinical entities presenting with thrombocytopenia, in particular the diagnosis of MDS must be excluded. A bone marrow aspirate and biopsy should normally have been done over the course of the disease and treatment, particularly in patients over 60 years of age, for those with systemic symptoms or abnormal signs such as increased peripheral blast cells.

    If a loss of efficacy and abnormal peripheral blood smear occur, treatment with romiplostim should be discontinued, physical examination should be performed and bone marrow biopsy with appropriate staining for reticulin should be considered. If efficacy is maintained but abnormal peripheral blood smear is observed consideration should be given to a bone marrow biopsy and alternative ITP treatment options.

    Concurrent anaemia and leucocytosis (within a 4-week window) may occur in patients regardless of splenectomy status, but have been seen more often in patients who have had a prior splenectomy. Monitoring of these parameters should be considered in patients treated with romiplostim.

    Pregnancy and Lactation


    Romiplostim is contraindicated in pregnancy.

    Safety in human pregnancy has not been established.

    Animal studies have shown transplacental passage, increased foetal platelet counts, post-implantation loss and a slight increase in peri-natal pup mortality.

    The use of all medication in pregnancy should be avoided whenever possible; particularly in the first trimester. Non-drug treatments should also be considered. When essential, a medication with the best safety record over time should be chosen, employing the lowest effective dose for the shortest possible time. Polypharmacy should be avoided. Teratogens taken in the pre-embryonic period, often quoted as lasting until 14 to 17 days post-conception, are believed to have an all-or-nothing effect. Where drugs have a short half-life, and when the date of conception is certain, this may allow women to be reassured where drug exposure has occurred within this time frame. Further advice may be available from the UK National Teratology Information Service (NTIS) and through ToxBase, available via password on the internet ( ) or if this is unavailable at the backup site ( ).


    Romiplostim is contraindicated in breastfeeding.

    To date, safety in human breastfeeding has not been established. It is unknown if romiplostim is excreted in human milk. A risk to the suckling child cannot be excluded.

    Neonates, infants born prematurely, those with low birth weight, those with an unstable gastrointestinal function or who have serious illnesses may require special consideration. For any infant, if a drug is prescribed to the nursing mother, it should be at the lowest practical dose and for the shortest time. When drug administration is unavoidable and breastfeeding is to continue, minimisation of exposure of the infant to the drug may sometimes be achieved by timing the maternal doses to just after a feeding episode. Infants exposed to drugs via breast milk should be monitored for unusual signs or symptoms. Interactions between the drug received by the infant from the mother's milk and medication prescribed for the infant should also be considered, for example, when the drug given to the infant may prevent metabolism of the drug received via breast milk.
    Specialist advice is available from the UK Drugs in Lactation Advisory Service at

    Side Effects

    Alcohol intolerance
    Antibody formation
    Aplastic anaemia
    Biopsy bone marrow abnormal
    Bone marrow failure
    Breathing difficulties
    Changes of blood pressure
    Chest pain
    Decreased appetite
    Deep vein thrombosis (DVT)
    Disturbances in accommodation
    Dream abnormalities
    Dry throat
    Eye disorder
    Eye pruritus
    Feeling hot
    Gastro-intestinal disturbances
    Hair growth abnormal
    Hypersensitivity reactions
    Increase in lactate dehydrogenase
    Increase in serum transaminases
    Increased bone marrow reticulin
    Increased heart rate
    Increased lacrimation
    Increased platelet count
    Influenza-like symptoms
    Local reaction at injection site
    Multiple myeloma
    Muscle spasm
    Musculoskeletal disturbances
    Myocardial infarction
    Nasal congestion
    Painful extremities
    Peripheral ischaemia
    Peripheral neuropathy
    Pulmonary embolism
    Reduced platelet count
    Rise in body temperature
    Skin disorder
    Skin odour changes
    Superficial tooth discolouration
    Superficial vein thrombophlebitis
    Transverse sinus thrombosis
    Visual disturbances
    Weight changes


    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: November 2018

    Reference Sources

    Summary of Product Characteristics: Nplate vial. Amgen Ltd. Revised January 2021.

    Summary of Product Characteristics: Nplate with Reconstitution Pack. Amgen Ltd. Revised January 2018.

    NICE Evidence Services Available at: Last accessed: 8 November 2018.

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