ITP Injection Dosing & Administration | Nplate® (romiplostim)

Once-weekly Nplate^® can provide ITP control—have confidence in your choice¹

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Titration guide

Administration videos

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ONCE-WEEKLY administration¹

NO known drug interactions*

NO calcium or other dietary restrictions¹

*No formal drug interaction studies of Nplate^® have been performed.²

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Nplate^® dosing calculator

4 easy steps to calculate your patient's total Nplate^® injection volume¹¹

This tool provides calculation assistance only. It is not designed or intended to replace the physician’s clinical judgment in determining the appropriate dose for his or her patient.

Adult patients: Actual body weight at initiation of therapy should always be used when calculating the dose.
Pediatric patients: Base future dose adjustments on changes in platelet counts and body weight (reassessment of body weight every 12 weeks is recommended).¹

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STEP 3: Note total dose (mcg) and injection volume (mL)

Patient's Total Dose--

Patient's Total Dose (mcg) =
patient's weight (kg) x dose (mcg/kg)

Injection Volume--

Injection Volume (mL) =
patient's total dose

500 mcg/mL

STEP 4: Determine Nplate^® vial(s) required for single use

Using your patient's total dose and/or injection volume calculated in STEP 3, refer to the full Prescribing Information to determine the appropriate vial required for single-use dose

Watch the directions for Nplate^® reconstitution and administration

^†The recommended starting dose for Nplate^® is 1 mcg/kg.¹

Individualize ITP treatment with Nplate^®

Tips for dosing success

The initial dose for Nplate^® is 1 mcg/kg based on actual body weight¹
Administer Nplate^® as a once-weekly subcutaneous injection with dose adjustments based upon the platelet count response¹
See the Nplate^® titration guide to Start, Adjust, Maintain, and Monitor
Use the lowest dose of Nplate^® to achieve and maintain a platelet count ≥ 50 x 10⁹/L as necessary to reduce the risk for bleeding¹
As the injection volume may be very small, use a syringe that contains 0.01 mL graduations¹

Watch the directions for Nplate^® reconstitution and administration

^†The recommended starting dose for Nplate^® is 1 mcg/kg.¹

Dose for ITP control

Use the lowest dose of Nplate^® to achieve and maintain a platelet count ≥ 50 x 10⁹/L as necessary to reduce the risk for bleeding. Administer Nplate^® as a once-weekly subcutaneous injection with dose adjustments based upon the platelet count response. Do not exceed maximum weekly dose of 10 mcg/kg.¹

Adult patients: Actual body weight at initiation of therapy should always be used when calculating the dose.
Pediatric patients: Base future dose adjustments on changes in platelet counts and body weight (reassessment of body weight every 12 weeks is recommended).¹

Start

Initial dose: 1 mcg/kg
based on actual
body weight.¹ If calculated dose is less than 23 mcg, additional dilution with 0.9% Sodium Chloride is required.
Please refer to Table 1 in the Prescribing Information for instructions on dilution.

Adjust

Obtain weekly complete blood counts (CBCs), including platelet counts, during dose adjustment until stable platelet count ≥ 50 × 10⁹/L is achieved for ≥ 4 weeks without further changes in dose.¹

If platelet count is < 50 × 10⁹/L, increase by 1 mcg/kg.¹
If platelet count is > 200 × 10⁹/L for 2 consecutive weeks, reduce by 1 mcg/kg.¹
If platelet count is > 400 × 10⁹/L, DO NOT DOSE. Assess platelet count weekly. After platelet count is < 200 × 10⁹/L, resume at dose decreased by 1 mcg/kg.¹

Maintain

If platelet count is 50–200 × 10⁹/L, maintain dose and assess CBCs weekly until stable platelet count ≥ 50 × 10⁹/L is achieved for ≥ 4 weeks without further changes in dose.¹

MONITOR

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 2 weeks following discontinuation of Nplate^®.¹

Titrate Nplate^® according to individual patient response; adjust the weekly dose of Nplate^® by increments of 1 mcg/kg until the patient achieves a platelet count of ≥ 50 x 10⁹/L, as necessary, to reduce the risk of bleeding.¹

Do not exceed maximum weekly dose of 10 mcg/kg.¹

To mitigate against medication errors (both overdose and underdose), ensure that the preparation and administration instructions in the full Prescribing Information are followed.

Discontinuation
Discontinue Nplate^® if the platelet count does not increase to a level sufficient to avoid clinically important bleeding after 4 weeks of Nplate^® therapy at the maximum weekly dose of 10 mcg/kg. Obtain CBCs, including platelet counts, weekly for at least 2 weeks following discontinuation of Nplate^®.¹

Dose for confidence

See what Nplate^® dosing^‡ and administration might look like for you and your practice

Always reference the complete dosing and administration information in the full prescribing information for Nplate^®. Download now

Nplate^® Adult Dosing and Reconstitution

Nplate^® Adult Dosing Perspectives

Dosing and Reconstituting Nplate^®(video at left)(video at top) provides an overview of the preparation and administration process.

Nplate^® Dosing Perspectives (video at right)(video at bottom) follows two leading hematologists, Dr. Michael Tarantino from the Bleeding and Clotting Disorders Institute, IL, and Dr. Terry Gernsheimer from the Seattle Cancer Care Alliance, WA, as they discuss Nplate^® dosing and titration to address their patients' needs.

^‡The recommended starting dose for Nplate^® is 1 mcg/kg.¹ Please see the Nplate^® full Prescribing Information for complete dosing instructions, including guidelines for dose adjustments.

NEXT Learn about the Nplate^® mechanism of action

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 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.

Adverse Reactions

Adult ITP

In the placebo-controlled trials of adult ITP patients, headache was the most commonly reported adverse drug reaction, occurring in 35% of patients receiving Nplate^® and 32% of patients receiving placebo. Adverse drug reactions in adults with a ≥ 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%).

The safety profile of Nplate^® was similar across patients, regardless of ITP duration. The following adverse reactions (at least 5% incidence and at least 5% more frequent with Nplate^® compared with placebo or standard of care) occurred in Nplate^® patients with ITP duration up to 12 months: bronchitis, sinusitis, vomiting, arthralgia, myalgia, headache, dizziness, diarrhea, upper respiratory tract infection, cough, nausea and oropharyngeal pain. The adverse reaction of thrombocytosis occurred with an incidence of 2% in adults with ITP duration up to 12 months.

Pediatric ITP

The most common adverse reactions experienced by ≥ 5% of patients receiving Nplate^® with ≥ 5% higher incidence in the Nplate^® arm across the two placebo-controlled trials were contusion (41%), upper respiratory tract infection (31%), oropharyngeal pain (25%), pyrexia (24%), diarrhea (20%), rash (15%), and upper abdominal pain (14%).

In pediatric patients of age ≥ 1 year receiving Nplate^® for ITP, adverse reactions with an incidence of ≥ 25% in the two randomized trials were: contusion (41%), upper respiratory tract infection (31%), and oropharyngeal pain (25%).

In a long-term, single arm, open label pediatric safety study, headache occurred in 78/203 patients (38%); the incidence rates of other adverse reactions were similar to those reported in the placebo-controlled studies.

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.

INDICATIONS

Nplate^® is a thrombopoietin receptor agonist indicated for the treatment of thrombocytopenia in adult patients with immune thrombocytopenia (ITP) who have had an insufficient response to corticosteroids, immunoglobulins, or splenectomy. Nplate^® is indicated for the treatment of thrombocytopenia in pediatric patients 1 year of age and older with ITP for at least 6 months 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 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.

Nplate® dosing calculator

4 easy steps to calculate your patient's total Nplate® injection volume11

Individualize ITP treatment with Nplate®