How Nplate® May Help

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Results with Nplate®

When given regularly, Nplate® has been shown to increase and sustain platelet countsA measure of how many platelets are in the blood, usually expressed in thousands per microliter (e.g., 50,000) or in 109 per liter (e.g., 50 x 109/L). A count of 50 x 109/L is equal to a count of 50,000 per microliter..1

Nplate® was studied in 2 medical studies including over 120 patients and lasting 6 months. One study evaluated chronic ITP adult patients who had already had their spleens removed, and the other study evaluated chronic ITP adult patients who had not had their spleens removed.1

For 6 months, patients received either Nplate® therapy or placeboa substance that does not contain any study drug., and patients were allowed to stay on their original standard of care ITP medications (azathioprine, danazol, and/or corticosteroids). Patients also received rescue therapiesNon-surgical medical treatment to help prevent life-threatening bleeding (as defined in Nplate® medical studies). as needed to prevent or treat bleeding.1

Durable platelet response

In both studies, the primary goal of treatment was to achieve a durable platelet response.Keeping platelet counts at 50,000 per microliter or above for at least 6 of the last 8 weeks of the studies, without receiving any rescue medication (as defined in Nplate® medical studies).1

No one who received rescue therapies at any time during the 6-month study could be considered to have a durable platelet response. Studying Nplate® this way helped show how well Nplate® worked by taking the effects of other ITP medications into account. In the two studies:

  • 61% (25/41) of patients taking Nplate® who did not have a splenectomy met the goal, versus 5% (1/21) of patients taking placebo.1,2
  • 38% (16/42) of patients taking Nplate® who had already had a splenectomy met the goal, versus 0% (0/21) of patients taking placebo.1,2

In addition to durable platelet response, the studies also measured the following kinds of platelet response:

  • Weekly platelet response.Platelet counts at 50,000 per microliter or above during a given week (as defined in Nplate® medical studies).
  • Transient platelet responseFour or more weekly platelet responses in which patients kept platelet counts at 50,000 per microliter or above (as defined in Nplate® medical studies). Platelet counts within 8 weeks of rescue therapy were not included..
  • Overall platelet responseAll patients who had either a transient platelet response or a durable platelet response (as defined in Nplate® medical studies).1:
    • 88% (36/41) of patients taking Nplate® who had not had a splenectomy A surgical procedure that removes the spleen. had an overall platelet response, versus 14% (3/21) of patients taking placebo.1,2
    • 79% (33/42) of patients taking Nplate® who had already had a splenectomy had an overall platelet response, versus 0% (0/21) of patients taking placebo.1,2

Some of the patients from the 6-month studies, along with additional patients, were also enrolled in a long-term study that evaluated Nplate® in patients who took it for more than 5 years. The safety profile of Nplate® in the long-term study was consistent with that in the 6-month trials.3,4 The most common side effects were mild, including headache, nasopharyngitis (inflammation of the nasal passages and the throat), and fatigue. They did not occur more often with longer use of Nplate®.4 Please see Important Safety Information to learn about additional side effects associated with Nplate®.

Seeing results

The majority of patients in the 6-month studies experienced an increase in platelet counts within 1 to 2 weeks and achieved a platelet response (≥ 50,000 per microliter) within 2 to 3 weeks.2 Not all patients will respond to Nplate®. Individual patient results will vary.

Some patients were able to stop taking other ITP treatments when they took Nplate®

Among patients who were taking other ITP treatments, 87% (20/23) of patients taking Nplate® were able to receive lower doses of their other medicines, or even stop taking those medicines altogether, versus 38% (6/16) of patients taking placebo.2 Not all patients will respond to Nplate®. Individual patient results will vary.

Next: Nplate® Side Effects >

Indication

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 www.fda.gov/medwatch, or call 1-800-FDA-1088.

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

References:

  1. Nplate® (romiplostim) prescribing information, Amgen. V2 Issue Date: 1/2011.
  2. Kuter DJ, Bussel JB, Lyons RM, et al. Efficacy of romiplostim in patients with chronic immune thrombocytopenic purpura: a double-blind randomised controlled trial. Lancet. 2008;371:395-403.
  3. Bussel JB, Kuter DJ, Pullarkat V, et al. Safety and efficacy of long-term treatment with romiplostim in thrombocytopenic patients with chronic ITP. Blood. 2009;113:2161-2171.
  4. Kuter DJ, Bussel JB, Newland A, et al. Long-term efficacy and safety of romiplostim treatment of adult patients with chronic immune thrombocytopenia (ITP): final report from an open-label extension study. Blood. 2010;116:Abstract 68. Abstract and poster presented at 52nd American Society of Hematology Annual Meeting and Exposition; Orlando, FL.