Must-read for patients: Dosage and usage of Roprostim/Romigrastim

Romiplostim is a fusion protein thrombopoietin (TPO) peptide analog that increases platelet counts by binding to and activating the human TPO receptor. It is used to treat thrombocytopenia associated with chronic immune thrombocytopenia (ITP ), and is also used for adult patients with acute radiation syndrome hematopoietic syndrome. Roprostim injection is a powder that can be mixed with liquid and injected subcutaneously by a doctor or nurse in the medical office; the recommended dose is based on body weight and the dose is adjusted according to the platelet count response.

For patients with ITP, the initial dose of loplastin is 1 mcg/kg. As needed, adjust the weekly dose of Roprostim in 1mcg/kg increments until the patient's platelet count is ≥50×10^9/L to reduce the risk of bleeding; do not exceed the maximum weekly dose of 10mcg/kg. In clinical studies, the majority of adult patients who responded to roprostim achieved and maintained platelet counts ≥50×10^9/L at a median dose of 2-3mcg/kg, and pediatric patients achieved a median dose of 5.5mcg/kg.

For patients with acute radiation syndrome and hematopoietic syndrome: the recommended dose of loplastin is 10mcg/kg, once subcutaneously injected. Administer as soon as possible after suspected or confirmed exposure to radiation levels >2 Gray (Gy). Use ropremilast whether or not a complete blood count (CBC) is available. Estimate the patient's whole-body absorbed radiation dose (i.e., radiation exposure level) based on information provided by public health authorities, biological dosimetry (if available), or clinical findings (such as timing of emesis episodes or lymphocyte depletion kinetics).

If the patient's platelet count is <50×10^9/L, increase the dose of loprostim by 1mcg/kg. If the platelet count is >200×10^9/L and ≤400×10^9/L for 2 consecutive weeks, reduce the dose by 1mcg/kg. Do not administer if platelet count is >400×10^9/L. Continue to evaluate platelet counts weekly. After the platelet count drops to less than 200×10^9/L, resume roplastin at a reduced dose of 1 mcg/kg.

When necessary, use the lowest dose of roplastin to achieve and maintain a platelet count≥50×10^9/L to reduce the risk of bleeding. If platelet counts have not increased to a level sufficient to avoid clinically important bleeding after 4 weeks of treatment with ropruprimostat at a maximum dose of 10 mcg/kg per week, discontinue ropruprimostim injections.

Roprostim Injections controlITP but do not cure it. Keep getting your injections even if you feel well;Roplastin injection does not work for everyone. If your platelet levels don't increase enough after a period of time after receiving Roprostim injections, your doctor will stop the drug. The doctor may also order a blood test to find out why Roprostim injection is not working for the patient.