Amgen Megakaryopoiesis Protein 2 (AMG 531) in Thrombocytopenic Subjects With Immune Thrombocytopenic Purpura (ITP)

An Open-label, Unit Dose-finding Study Evaluating the Safety and Efficacy of Amgen Megakaryopoiesis Protein 2 (AMG 531) in Thrombocytopenic Subjects With Immune Thrombocytopenic Purpura (ITP)

Sponsors

Lead Sponsor: Amgen

Source Amgen
Brief Summary

The purpose of this study is to assess the safety and tolerability of AMG 531 (romiplostim), a novel thrombopoiesis‐stimulating peptibody, and its effect on platelet counts in adults with immune thrombocytopenic purpura.

Overall Status Completed
Start Date December 2, 2002
Completion Date July 19, 2004
Primary Completion Date July 19, 2004
Phase Phase 1/Phase 2
Study Type Interventional
Primary Outcome
Measure Time Frame
Number of Participants With Adverse Events From first dose through 8 weeks after last dose of study drug (11 weeks)
Number of Participants With Positive Anti-Romiplostim Antibodies Days 29 and 78
Secondary Outcome
Measure Time Frame
Number of Participants Who Achieved a Targeted Therapeutic Platelet Response Baseline and after first dose (days 3, 5, 8, 10, 12, 15, and days 17 and 19 for participants dosed on day 22) and after second dose (days 17, 19, and 22 for participants dosed on day 15, and days 24, 26, 29, 32, 36, 43, 50, 64, and 78 in all participants)
Number of Participants With an Increase in Platelet Count of ≥ 20 x 10⁹ Cells/L From Baseline Baseline and after first dose (days 3, 5, 8, 10, 12, 15, and days 17 and 19 for participants dosed on day 22) and after second dose (days 17, 19, and 22 for participants dosed on day 15, and days 24, 26, 29, 32, 36, 43, 50, 64, and 78 in all participants)
Number of Participants With Peak Platelet Counts of ≥ 100 x 10⁹ Cells/L After first dose (days 3, 5, 8, 10, 12, 15, and days 17 and 19 for participants dosed on day 22), and after second dose (days 17, 19, and 22 for participants dosed on day 15, and days 24, 26, 29, 32, 36, 43, 50, 64, and 78 for all participants)
Number of Participants With Peak Platelet Counts of ≥ 450 x 10⁹ Cells/L After first dose (days 3, 5, 8, 10, 12, 15, and days 17 and 19 for participants dosed on day 22), and after second dose (days 17, 19, and 22 for participants dosed on day 15, and days 24, 26, 29, 32, 36, 43, 50, 64, and 78 for all participants)
Change From Baseline to Peak Platelet Level Baseline and after first dose (days 3, 5, 8, 10, 12, 15, and days 17 and 19 for participants dosed on day 22) and after second dose (days 17, 19, and 22 for participants dosed on day 15, and days 24, 26, 29, 32, 36, 43, 50, 64, and 78 in all participants)
Time to Peak Platelet Count From first dose of study drug to day 15 or 22, and from the second dose of study drug (day 15 or 22) to day 78
Duration Within the Targeted Therapeutic Range From first dose of study drug to day 15 or 22, and from the second dose of study drug (day 15 or 22) to day 78
Enrollment 16
Condition
Intervention

Intervention Type: Drug

Intervention Name: Romiplostim

Description: Administered subcutaneously on day 1 and on day 15 or 22 if the platelet count was ≤ 50 x 10⁹/L and not rising, peak platelet count was ≤ 450 x 10⁹/L and no serious adverse events related to treatment were observed.

Arm Group Label: Romiplostim

Eligibility

Criteria:

Inclusion Criteria:

- Greater than or equal to 3 months history of ITP, regardless of splenectomy status, and completion of at least 1 prior treatment for ITP

- 2 of 3 pretreatment platelet counts that were less than 30 x 10^9/L (if not currently on ITP therapy) or less than 50 x 10^9/L (if currently receiving corticosteroids for ITP therapy)

- Ability to give informed consent

Exclusion Criteria:

- Known history of arterial thrombosis, active malignancy, or bone marrow stem cell disorder

Gender: All

Minimum Age: N/A

Maximum Age: N/A

Healthy Volunteers: No

Overall Official
Last Name Role Affiliation
MD Study Director Amgen
Verification Date

November 2019

Responsible Party

Type: Sponsor

Keywords
Has Expanded Access No
Condition Browse
Number Of Arms 1
Arm Group

Label: Romiplostim

Type: Experimental

Description: Participants will receive a maximum of 2 administrations of romiplostim by subcutaneous injection, the first on day 1 of the study and the second on day 15 or 22 depending on the participant's platelet count. Romiplostim doses to be tested were 30, 100, 300, and 500 μg.

Study Design Info

Intervention Model: Sequential Assignment

Primary Purpose: Treatment

Masking: None (Open Label)

Source: ClinicalTrials.gov