Open Label Extension Study of AMG 531 in Thrombocytopenic Subjects With Immune (Idiopathic) Thrombocytopenic Purpura (ITP)
The purpose of this study is to determine the safety of AMG 531 as a long-term treatment in thrombocytopenic subjects with ITP, to evaluate the long-term platelet response to AMG 531, and to evaluate changes in patient reported outcomes due to the use of AMG 531. Subjects must have previously completed an AMG 531 ITP study.
Idiopathic Thrombocytopenic Purpura
Biological: AMG 531
|Study Design:||Allocation: Randomized
Endpoint Classification: Safety/Efficacy Study
Intervention Model: Single Group Assignment
Masking: Open Label
Primary Purpose: Treatment
|Official Title:||An Open Label Study Evaluating the Safety and Efficacy of Long-Term Dosing of AMG 531 in Thrombocytopenic Subjects With Immune (Idiopathic) Thrombocytopenic Purpura (ITP)|
- Adverse Events [ Time Frame: Duration of treatment plus 8 weeks (up to 285 weeks) ] [ Designated as safety issue: Yes ]One or more occurrences of one or more adverse events within the participant up to 8 weeks after the end of treatment. Participants with more than one event were only counted once.
- Platelet Response [ Time Frame: Duration of treatment (up to 277 weeks) ] [ Designated as safety issue: No ]Platelet count of ≥ 50 x 10^9/L at any time on study, excluding platelet counts within 8 weeks after receiving any rescue medications
- Reduction or Discontinuation of Concurrent ITP Therapies [ Time Frame: Duration of treatment (up to 277 weeks) ] [ Designated as safety issue: No ]Reduction or discontinuation of concurrent immune (idiopathic) thrombocytopenic purpura (ITP) therapies (corticosteroids, danazol, azathioprine)
|Study Start Date:||August 2004|
|Study Completion Date:||July 2010|
|Primary Completion Date:||January 2010 (Final data collection date for primary outcome measure)|
Experimental: AMG 531
Active investigational product
Biological: AMG 531
Weekly subcutaneous dosing based on screening weight and platelet count. Starting dose is at 1mcg/kg up to a maximum dose of 10mcg/kg. AMG 531 is supplied in a 5 mL single use glass vial as a sterile, white, preservative-free, lyophilized powder.