A Phase 3 interventional study of Romiplostim and Predniso(lo)ne in Primary Immune Thrombocytopenia, sponsored by Amgen. Recruiting at 3 sites in United States. Open to participants aged 18 Years to 100 Years. Per ClinicalTrials.gov, last updated 2026-09-17.
Sponsored by Amgen · Phase 3, Interventional, and Treatment
Help build ClinicalTrials.gg — short surveys, remote interviews or testing, in your language. Take part →
Among 29 studies testing romiplostim in Purpura, Thrombocytopenic, Idiopathic — 5 open to participants now, 6 under way, 2 of them phase 3. romiplostim · Purpura, Thrombocytopenic, Idiopathic.
Among the 29 studies testing romiplostim in Purpura, Thrombocytopenic, Idiopathic, this one is the 11th largest by planned enrollment, is one of 2 that started in 2026, is one of 13 in phase 3, and was the 29th registered.
504 studies on the registry are indexed under Purpura, Thrombocytopenic, Idiopathic; 159 are open to participants now.
Browse Purpura, Thrombocytopenic, Idiopathic studies →5 of the 29 studies testing romiplostim in Purpura, Thrombocytopenic, Idiopathic are open now, in 3 countries. Recruiting first, the newest first:
The First Affiliated Hospital of Soochow University · Sites in China
Ages 18+
The First Affiliated Hospital of Soochow University · Sites in China
Ages 14+
Wuhan Union Hospital, China · Sites in China
Ages 18–75
Nahda University · Sites in Egypt
Ages 18–65
By country, each count listing its studies:
romiplostim: first FDA approval 2008 (NPLATE), first EMA approval 2009. What it is approved for, and how studies give it, is on its page →
Of the 103 Purpura, Thrombocytopenic, Idiopathic studies recruiting now, 49 (48%) set no upper age limit and 42 (41%) stop at 75 or younger; 27 take children under 18; 4 take healthy volunteers.
This study: 18 Years to 100 Years · all sexes · no healthy volunteers.
The full table on the hub →This tab as a report to print or save as PDF → With an account.
29 studies; the count open now beside each. This study's row is marked.
A study in two phases is counted once above. Listed by phase, each with its combined phases: Phase 1 3 · Phase 2 11 · Phase 3 13 · Phase 4 3
First in 2002; this study’s year is marked. 2 started in 2026.
By drug class, each counting the studies that test any of its medicines:
This study's planned enrollment of 126 is above the median of 58 across 377 interventional studies indexed under Purpura, Thrombocytopenic, Idiopathic.
Median enrollment 62 across the 29 interventional studies. Of the 20 that completed or were terminated, 12 (60%) have results posted.
This tab as a report to print or save as PDF → With an account.
19 of 29 have an industry lead sponsor. The 10 most frequent:
Amgen is the lead sponsor of 1,047 studies on the registry; 51 are open to participants now.
Of its 246 completed or terminated interventional studies of FDA-regulated products, 166 (67%) have results posted.
18 studies in Purpura, Thrombocytopenic, Idiopathic by Amgen: 1 open now, 1 under way, 1 of them phase 3. Of 17 finished, 13 (76%) have results posted.
Among the 18 studies in Purpura, Thrombocytopenic, Idiopathic by Amgen, this one is the 6th largest by planned enrollment of the 15 interventional ones that give a count, is the only one that started in 2026, is one of 10 in phase 3, and was the 18th registered.
Amgen’s Purpura, Thrombocytopenic, Idiopathic studies by the year they started, since 2002.
2 of the studies testing romiplostim in Purpura, Thrombocytopenic, Idiopathic that are under way reach primary completion within a year, 0 of them phase 3. Phase 3 first, then by date:
| Study | Primary completion |
|---|---|
| NCT07206823The First Affiliated Hospital of Soochow UniversityEfficacy and Safety of Romiplostim N01 Combined With Rituximab in Patients With Oral TPO-RA-Refractory Primary Immune Thrombocytopenia | 2027-02-28 |
| NCT07612319The First Affiliated Hospital of Soochow UniversityRomiplostim for Oral TPO-RA Resistant ITP | 2027-09 |
Add all 2 to your calendar (.ics) → With an account.
Among the 29 studies testing romiplostim in Purpura, Thrombocytopenic, Idiopathic, from their registry updates:
Nothing recorded among them since 2026-09-25.
Among Amgen’s 18 in Purpura, Thrombocytopenic, Idiopathic:
Nothing recorded among them since 2026-09-25.
This tab as a report to print or save as PDF → With an account.
This Phase 3 study is designed to evaluate the efficacy and safety of romiplostim in combination with predniso(lo)ne compared with predniso(lo)ne alone in adults with previously untreated Primary Immune Thrombocytopenia (ITP).
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Diagnosis of primary ITP according to the 2019 International Consensus (ICR) that is previously untreated and requires treatment.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Platelets
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants will receive romiplostim administered subcutaneously (SC) in combination with predniso(lo)ne administered orally during Part 1 of the study. Participants who complete Part 1 of the study will enter Part 2 and continue participation for study assessments.
Drug: Romiplostim · Drug: Predniso(lo)ne
Participants will receive predniso(lo)ne administered orally during Part 1 of the study. Participants who complete Part 1 of the study will enter Part 2 and continue participation for study assessments.
Drug: Predniso(lo)ne
Administered subcutaneously.
Also known as: AMG 531, Nplate®
Administered orally.
Percentage of Participants With a Durable Platelet Response (DPR)
Time frame: 8 weeks
Time to Next Treatment (TTNT)
Time frame: 12 months
Cumulative Exposure to Corticosteroids
Time frame: 12 months
Change From Baseline in ITP Patient Assessment Questionnaire (ITP-PAQ)
Time frame: 12 months
Change in Summary Scores and Visual Analogue Scale (VAS) Scores per EuroQol 5-Dimension 5-Level (EQ 5D-5L)
Time frame: 12 months
Incidence of Hospitalization and Rescue Medication in Part 1
Time frame: 6 months
Number of Participants Experiencing Treatment-Emergent Adverse Events (TEAEs), Treatment-Emergent Serious Adverse Events (TESAEs), Treatment-Emergent Adverse Events of Interest (EOI), and Fatal TEAEs
Time frame: 12 months
Percentage of Participants With Clinically Significant Bleeding Events in the Immune Thrombocytopenia-specific Bleeding Assessment Tool (ITP-BAT)
Time frame: 6 months
Serum Trough Concentration (Ctrough) of Romiplostim
Time frame: 6 months
Number of Participants With Anti-Romiplostim Antibodies and Anti-Thrombopoietin (TPO) Antibodies
Time frame: 6 months
Plan to share: Yes — De-identified individual patient data for variables necessary to address the specific research question in an approved data sharing request.
Supporting information: Study protocol, Statistical analysis plan, Informed consent form, Clinical study report
Time frame: Data sharing requests relating to this study will be considered beginning 18 months after the study has ended and either 1) the product and indication have been granted marketing authorization in both the US and Europe or 2) clinical development for the product and/or indication discontinues and the data will not be submitted to regulatory authorities. There is no end date for eligibility to submit a data sharing request for this study.
Access criteria: Qualified researchers may submit a request containing the research objectives, the Amgen product(s) and Amgen study/studies in scope, endpoints/outcomes of interest, statistical analysis plan, data requirements, publication plan, and qualifications of the researcher(s). In general, Amgen does not grant external requests for individual patient data for the purpose of re-evaluating safety and efficacy issues already addressed in the product labelling. Requests are reviewed by a committee of internal advisors. If not approved, a Data Sharing Independent Review Panel will arbitrate and make the final decision. Upon approval, information necessary to address the research question will be provided under the terms of a data sharing agreement. This may include anonymized individual patient data and/or available supporting documents, containing fragments of analysis code where provided in analysis specifications. Further details are available at the URL below.
Data sharing details ↗ · www.amgen.com
Start is estimated for Aug 2026; primary completion for Sep 2029, 36 months later.
Of 41 industry-sponsored phase 3 interventional studies under Purpura, Thrombocytopenic, Idiopathic, half reached primary completion within 25 months of starting (the median), counting those still running; a quarter within 21 and three quarters within 44. This study's planned 36 months is above that.
Counting every sponsor, half of 57 studies reached it within 28 months; a quarter within 22 and three quarters within 49.
How these figures are worked out, and which studies are left out of them.
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
Contact study teamGet an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Studies of the drug tested here: Romiplostim
Purpura, Thrombocytopenic, Idiopathic →