Nplate (romiplostim) is a once-weekly subcutaneous injection used to treat low blood platelet counts (thrombocytopenia) resulting from specific medical conditions. Given by a healthcare professional, Nplate acts by mimicking the action of the natural hormone thrombopoietin (TPO), thereby stimulating the bone marrow to increase platelet production.

Nplate® (Romiplostim) Injection 125 mcg is a medication used primarily in the treatment of thrombocytopenia (low platelet counts), especially for patients with chronic immune (idiopathic) thrombocytopenic purpura (ITP) who have had an insufficient response to corticosteroids, immunoglobulins, or splenectomy.

 

Quick Facts

• Generic name: Romiplostim
• Brand name: Nplate
• Dosage form: Injection
• Strength: 125 mcg per vial (multiple strengths available)
• Administration: Subcutaneous injection (under the skin)
• Manufacturer: Amgen

How It Works

Romiplostim is a thrombopoietin receptor agonist. It works by stimulating the bone marrow to produce more platelets, thereby raising platelet counts and decreasing the risk of bleeding in individuals with ITP.

Indications

• Adults and pediatric patients (1 year and older) with chronic ITP who are refractory to other treatments (such as corticosteroids, IVIG, or splenectomy).

Dosing

• Starting dose: Often 1 mcg/kg once weekly, administered subcutaneously.
• Dose adjustment: May be adjusted weekly based on platelet response (target: ≥50,000/μL but ≤400,000/μL).
• 125 mcg vial: Intended for dose preparation; the actual dose administered will depend on the patient’s weight and platelet count.

Note: Dose modifications are made by a healthcare professional based on ongoing blood tests.

Administration

1. Preparation: Reconstituted with sterile water for injection, forming a clear and colorless solution.
2. Injected: Subcutaneously, usually by a healthcare provider.
3. Storage: Unopened vials are stored in the refrigerator. See manufacturer instructions post-reconstitution.

Side Effects

Common:

• Headache
• Fatigue
• Arthralgia (joint pain)
• Dizziness
• Insomnia

Serious:

• Increased risk of blood clots
• Bone marrow changes
• Worsening of blood disorders after discontinuation

Warnings and Precautions

• Risk of thrombosis (blood clots) if platelets rise too high.
• Progression of myelodysplastic syndromes (MDS) or acute myeloid leukemia (AML) if used for unapproved indications.
• Rebound thrombocytopenia: platelet count may drop sharply after stopping therapy—monitor closely.
• Regular monitoring of platelets and blood counts required.

Patient Counseling

• Do not self-inject unless trained by a healthcare professional.
• Attend all scheduled appointments and laboratory tests.
• Inform your doctor of any signs of bleeding or blood clots (e.g., unusual bruising, leg pain/swelling, chest pain, shortness of breath).