How Nplate® May Help

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How Nplate® May Help

Because chronic immune thrombocytopenia (ITP)An autoimmune disease in which the body's immune system attacks and destroys platelets. involves both the destruction of existing plateletsSmall cells that are made in the bone marrow and circulate through the bloodstream. Whenever there is damage to a blood vessel, platelets stick to the area to stop or prevent bleeding. and inadequate platelet production to make up for those being destroyed, one approach to help manage ITP is to boost platelet production.1-5 And that is exactly what Nplate® does.

Nplate® is a type of ITP treatment called a platelet booster. Just like your body's own thrombopoietin (TPO)The protein that stimulates the megakaryocytes in the bone marrow to produce platelets., Nplate® acts on cells in the bone marrow to produce more platelets, which may help reduce the risk of bruising and bleeding.6-9

Once-weekly Nplate® is given by a healthcare provider as a subcutaneous (sub-cue-tain-ee-us) injection under the skin. Patients cannot inject themselves with Nplate®.6

Learn more about how Nplate® works and how it is taken at the links below:


Nplate® is a man-made protein medicine used to treat low blood platelet counts in adults with chronic immune thrombocytopenia (ITP), when certain other medicines, or surgery to remove your spleen, have not worked well enough.

Nplate® is not for use in people with a precancerous condition called myelodysplastic syndrome (MDS) or low platelet count caused by any condition other than chronic (lasting a long time) immune thrombocytopenia (ITP). Nplate® is only used if your low platelet count and medical condition increase your risk of bleeding. Nplate® is used to try to keep your platelet count about 50,000 per microliter in order to lower the risk for bleeding. Nplate® is not used to make your platelet count normal.

Important Safety Information

What is the most important information I should know about Nplate®?

Nplate® can cause serious side effects:

Worsening of a precancerous blood condition to a blood cancer (leukemia): Nplate® is not for use in people with a precancerous condition called myelodysplastic syndromes (MDS) or for any condition other than chronic (lasting a long time) immune thrombocytopenia (ITP). If you have MDS and receive Nplate®, your MDS condition may worsen and become an acute leukemia. If MDS worsens to become acute leukemia you may die sooner from the acute leukemia.

Higher risk for blood clots:

  • You may have a higher risk of getting a blood clot if your platelet count becomes high during treatment with Nplate®. You may have severe complications or die from some forms of blood clots, such as clots that spread to the lungs or that cause heart attacks or strokes. Your healthcare provider will check your blood platelet counts and change your dose or stop Nplate® if your platelet counts get high.
  • If you have a chronic liver disease, you may get blood clots in the veins of your liver. This may affect your liver function.

Bone marrow changes (increased reticulin and possible bone marrow fibrosis): Nplate® may cause changes in your bone marrow, but these changes may improve if you stop taking Nplate®. These changes may lead to abnormal blood cells or your body making less blood cells. The mild form of these bone marrow changes is called "increased reticulin." It is not known if this may progress to a more severe form called "fibrosis." The mild form may cause no problems while the severe form may cause life-threatening blood problems. Signs of bone marrow changes may show up as abnormalities in your blood tests. Your healthcare provider will decide if abnormal blood tests mean that you should have bone marrow tests or if you should stop taking Nplate®.

Worsening low blood platelet count (thrombocytopenia) and risk of bleeding shortly after stopping Nplate®: When you stop receiving Nplate®, your low blood platelet count (thrombocytopenia) may become worse than before you started receiving Nplate®. These effects are most likely to happen shortly after stopping Nplate® and may last about 2 weeks. The lower platelet counts during this time period may increase your risk of bleeding, especially if you are taking a blood thinner or other medicine that affects platelets. Your healthcare provider will check your blood platelet counts for at least two weeks after you stop taking Nplate®. Call your healthcare provider right away to report any bruising or bleeding.

Lack or loss of response: If you do not experience results from Nplate®, your body may have created cells that are counteractive to Nplate®. Your healthcare provider will monitor your platelet counts and test your blood regularly to determine if this is an issue.

Blood test monitoring: Your healthcare provider will check your platelet count every week and change your dose of Nplate® as needed. This will continue until your healthcare provider decides that your dose of Nplate® can stay the same. After that, you will need to have blood tests every month. When you stop receiving Nplate®, you will need blood tests for at least 2 weeks to check if your platelet count drops too low.

What are the possible side effects of Nplate®?

  • Nplate® may cause serious side effects. See "What is the most important information I should know about Nplate®?"
  • The most common side effects of Nplate® are:
    • Headache
    • Joint pain
    • Dizziness
    • Trouble sleeping
    • Muscle tenderness or weakness
    • Pain in arms and legs
    • Abdominal pain
    • Shoulder pain
    • Indigestion
    • Tingling or numbness in hands and feet
  • These are not all the possible side effects of Nplate®. Tell your healthcare provider if you have any side effect that bothers you or that does not go away. For more information, ask your healthcare provider or pharmacist.
  • If you have any questions about this information, be sure to discuss them with your doctor. You are encouraged to report negative side effects of prescription drugs to the FDA. Visit, or call 1-800-FDA-1088.

Please see Prescribing Information and Medication Guide for more information about Nplate®.


  1. Gernsheimer T. Pathophysiology and thrombokinetics in autoimmune thrombocytopenia. Blood Rev. 2002;16:7-8.
  2. Houwerzijl EJ, Blom NR, van der Want JJ, et al. Ultrastructural study shows morphologic features of apoptosis and para-apoptosis in megakaryocytes from patients with idiopathic thrombocytopenic purpura. Blood. 2004;103:500-506.
  3. Kaushansky K. The molecular mechanisms that control thrombopoiesis. J Clin Invest. 2005;115:3339-3347.
  4. Emmons RV, Reid DM, Cohen RL, et al. Human thrombopoietin levels are high when thrombocytopenia is due to megakaryocyte deficiency and low when due to increased platelet destruction. Blood. 1996;87:4068-4071.
  5. Nichol JL. Endogenous TPO (eTPO) levels in health and disease: possible clues for therapeutic intervention. Stem Cells. 1998;16(suppl 2):165-175.
  6. Nplate® (romiplostim) prescribing information, Amgen.
  7. Rice L. Drug evaluation: AMG-531 for the treatment of thrombocytopenias. Curr Opin Investig Drugs. 2006;7:834-841.
  8. Neunert C, Lim W, Crowther M, et al. The American Society of Hematology 2011 evidence-based practice guideline for immune thrombocytopenia. Blood. 2011;117:4190-4207.
  9. Cines DB, McMillan R. Management of adult idiopathic thrombocytopenic purpura. Annu Rev Med. 2005;56:425-442.