Mechanism of action
Nplate® increases platelet production through binding and activation of the thrombopoietin (TPO) receptor, a mechanism analogous to endogenous TPO.1,21,2

A thrombopoietin (TPO) receptor agonist, Nplate® is an Fc-peptide fusion protein (peptibody) that contains 2 single-chain subunits, each having a region with 2 TPO receptor-binding domains.11

Nplate® has no amino acid sequence homology to eTPO.11 As with all therapeutic proteins, patients may develop antibodies to the therapeutic protein. In clinical studies of patients with ITP, the incidence of binding antibody development during treatment with Nplate® or a non-US-approved romiplostim product was 4% (50/1112). Of the patients with positive antibodies that developed to romiplostim or to TPO, 5 patients had neutralizing activity to romiplostim and none had neutralizing activity to TPO. No apparent correlation was observed between antibody activity and clinical effectiveness or safety.1,41,4

Review Nplate® safety across clinical trials. Learn more >

Learn about the mechanism of action of Nplate (romiplostim) to help restore stability

Nplate® mimics the body’s natural production of platelets1,31,3

Nplate® targets megakaryocyte and platelet development via the same pathway as eTPO.1,31,3

In normal thrombopoiesis
In adult chronic ITP, treated with Nplate®
Normal thrombopoiesis
Nplate (romiplostim) binds to the TPO receptor
Nplate (romiplostim) works to increase platelet production
In normal thrombopoiesis
In adult chronic ITP, treated with Nplate®
In adult chronic ITP, treated with Nplate®
Nplate® mechanism of action
Watch this instructional video to learn how Nplate® works.
Watch this video to learn how Nplate (romiplostim) works

Nplate® is a TPO mimetic that works to target megakaryocyte and platelet development via the same pathway as eTPO.1,31,3

Review dosing for once-weekly Nplate®. Learn more >

Nplate® is a TPO mimetic that works to target megakaryocyte and platelet development via the same pathway as eTPO.1,31,3

Review dosing for once-weekly Nplate®. Learn more >

Important Safety Information

Risk of Progression of Myelodysplastic Syndromes to Acute Myelogenous Leukemia

  • In Nplate® (romiplostim) clinical trials of patients with myelodysplastic syndromes (MDS) and severe thrombocytopenia, progression from MDS to acute myelogenous leukemia (AML) has been observed.
  • Nplate® is not indicated for the treatment of thrombocytopenia due to MDS or any cause of thrombocytopenia other than chronic ITP.

Thrombotic/Thromboembolic Complications

  • Thrombotic/thromboembolic complications may result from increases in platelet counts with Nplate® use. Portal vein thrombosis has been reported in patients with chronic liver disease receiving Nplate®.
  • To minimize the risk for thrombotic/thromboembolic complications, do not use Nplate® in an attempt to normalize platelet counts. Follow the dose adjustment guidelines to achieve and maintain a platelet count of ≥ 50 x 109/L.

Loss of Response to Nplate®

  • Hyporesponsiveness or failure to maintain a platelet response with Nplate® should prompt a search for causative factors, including neutralizing antibodies to Nplate®.
  • To detect antibody formation, submit blood samples to Amgen (1‑800‑772‑64361‑800‑772‑6436). Amgen will assay these samples for antibodies to Nplate® and thrombopoietin (TPO).
  • Discontinue Nplate® if the platelet count does not increase to a level sufficient to avoid clinically important bleeding after 4 weeks at the highest weekly dose of 10 mcg/kg.

Laboratory Monitoring

  • Obtain CBCs, including platelet counts, weekly during the dose adjustment phase of Nplate® therapy and then monthly following establishment of a stable Nplate® dose.
  • Obtain CBCs, including platelet counts, weekly for at least two weeks following discontinuation of Nplate®.

Adverse Reactions

  • In the placebo-controlled trials, headache was the most commonly reported adverse drug reaction, occurring in 35% of patients receiving Nplate® and 32% of patients receiving placebo. Headaches were usually of mild or moderate severity.
  • Most common adverse reactions (≥ 5% higher patient incidence in Nplate® versus placebo) were Arthralgia (26%, 20%), Dizziness (17%, 0%), Insomnia (16%, 7%), Myalgia (14%, 2%), Pain in Extremity (13%, 5%), Abdominal Pain (11%, 0%), Shoulder Pain (8%, 0%), Dyspepsia (7%, 0%), and Paresthesia (6%, 0%).
  • Nplate® administration may increase the risk for development or progression of reticulin fiber formation within the bone marrow. This formation may improve upon discontinuation of Nplate®. In a clinical trial, one patient with ITP and hemolytic anemia developed marrow fibrosis with collagen during Nplate® therapy.


Women who become pregnant during Nplate® treatment are encouraged to enroll in Amgen's Pregnancy Surveillance Program. Patients or their physicians should call 1‑800‑77‑AMGEN1‑800‑77‑AMGEN (1‑800‑772‑64361‑800‑772‑6436) to enroll.

Indication

Nplate® is a thrombopoietin receptor agonist indicated for the treatment of thrombocytopenia in patients with chronic immune thrombocytopenia (ITP) who have had an insufficient response to corticosteroids, immunoglobulins, or splenectomy.

Nplate® is not indicated for the treatment of thrombocytopenia due to myelodysplastic syndrome (MDS) or any cause of thrombocytopenia other than chronic ITP. Nplate® should be used only in patients with ITP whose degree of thrombocytopenia and clinical condition increase the risk for bleeding. Nplate® should not be used in an attempt to normalize platelet counts.

Please see full Prescribing Information and Medication Guide.

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Important Safety Information

Risk of Progression of Myelodysplastic Syndromes to Acute Myelogenous Leukemia

  • In Nplate® (romiplostim) clinical trials of patients with myelodysplastic syndromes (MDS) and severe thrombocytopenia, progression from MDS to acute myelogenous leukemia (AML) has been observed.
  • Nplate® is not indicated for the treatment of thrombocytopenia due to MDS or any cause of thrombocytopenia other than chronic ITP.

Thrombotic/Thromboembolic Complications

  • Thrombotic/thromboembolic complications may result from increases in platelet counts with Nplate® use. Portal vein thrombosis has been reported in patients with chronic liver disease receiving Nplate®.
  • To minimize the risk for thrombotic/thromboembolic complications, do not use Nplate® in an attempt to normalize platelet counts. Follow the dose adjustment guidelines to achieve and maintain a platelet count of ≥ 50 x 109/L.

Loss of Response to Nplate®

  • Hyporesponsiveness or failure to maintain a platelet response with Nplate® should prompt a search for causative factors, including neutralizing antibodies to Nplate®.
  • To detect antibody formation, submit blood samples to Amgen (1‑800‑772‑64361‑800‑772‑6436). Amgen will assay these samples for antibodies to Nplate® and thrombopoietin (TPO).
  • Discontinue Nplate® if the platelet count does not increase to a level sufficient to avoid clinically important bleeding after 4 weeks at the highest weekly dose of 10 mcg/kg.

Laboratory Monitoring

  • Obtain CBCs, including platelet counts, weekly during the dose adjustment phase of Nplate® therapy and then monthly following establishment of a stable Nplate® dose.
  • Obtain CBCs, including platelet counts, weekly for at least two weeks following discontinuation of Nplate®.

Adverse Reactions

  • In the placebo-controlled trials, headache was the most commonly reported adverse drug reaction, occurring in 35% of patients receiving Nplate® and 32% of patients receiving placebo. Headaches were usually of mild or moderate severity.
  • Most common adverse reactions (≥ 5% higher patient incidence in Nplate® versus placebo) were Arthralgia (26%, 20%), Dizziness (17%, 0%), Insomnia (16%, 7%), Myalgia (14%, 2%), Pain in Extremity (13%, 5%), Abdominal Pain (11%, 0%), Shoulder Pain (8%, 0%), Dyspepsia (7%, 0%), and Paresthesia (6%, 0%).
  • Nplate® administration may increase the risk for development or progression of reticulin fiber formation within the bone marrow. This formation may improve upon discontinuation of Nplate®. In a clinical trial, one patient with ITP and hemolytic anemia developed marrow fibrosis with collagen during Nplate® therapy.

Women who become pregnant during Nplate® treatment are encouraged to enroll in Amgen's Pregnancy Surveillance Program. Patients or their physicians should call 1‑800‑77‑AMGEN1‑800‑77‑AMGEN (1‑800‑772‑64361‑800‑772‑6436) to enroll.

Indication

Nplate® is a thrombopoietin receptor agonist indicated for the treatment of thrombocytopenia in patients with chronic immune thrombocytopenia (ITP) who have had an insufficient response to corticosteroids, immunoglobulins, or splenectomy.

Nplate® is not indicated for the treatment of thrombocytopenia due to myelodysplastic syndrome (MDS) or any cause of thrombocytopenia other than chronic ITP. Nplate® should be used only in patients with ITP whose degree of thrombocytopenia and clinical condition increase the risk for bleeding. Nplate® should not be used in an attempt to normalize platelet counts.

Please see full Prescribing Information and Medication Guide.

References: 1. Nplate® (romiplostim) prescribing information, Amgen. 2. Gernsheimer TB, George JN, Aledort LM, et al. Evaluation of bleeding and thrombotic events during long-term use of romiplostim in patients with chronic immune thrombocytopenia (ITP). J Thromb Haemost. 2010;8:1372-1382. 3. Kaushansky K. The molecular mechanisms that control thrombopoiesis. J Clin Invest. 2005;115:3339-3347. 4. Kuter DJ, Bussel JB, Newland A, et al. Long-term treatment with romiplostim in patients with chronic immune thrombocytopenia: safety and efficacy. Br J Haematol. 2013;161:411-423.

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