Immune Thrombocytopenia (ITP)Phase 1/2NCT07043946
A Phase 1b/2a Study of Budoprutug in Subjects With Immune Thrombocytopenia (ITP)
A Phase 1/2 study testing Budoprutug in people with Immune Thrombocytopenia (ITP) and ITP, run by Climb Bio, Inc. at 20 sites in 5 countries.
Trial summary
The main objective is to assess the safety and tolerability of budoprutug in adults with ITP. Pharmacokinetics, pharmacodynamics, and preliminary clinical efficacy will also be assessed. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Immune Thrombocytopenia (ITP), ITP, Biologics
- What is being tested?
- Budoprutug
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 24 participants
- Where
- 20 sitesin 5 countries
- Study dates
- 30 Jun 2025to Aug 2028
- Phase
- Phase 1/2
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Aged 18 years at the time of consent.
- Platelet count < 30,000/µL despite an adequate trial of at least one prior therapeutic attempt. Platelet counts of < 30,000/µL must be confirmed on 2 occasions at least 5 days apart, but no more than 14 days apart.
- Partial thromboplastin time < 1.5 x upper limit of normal (ULN), prothrombin time < 1.5 x ULN, total bilirubin < 1.5 x ULN unless due to Gilbert's syndrome, or an international normalized ratio < 1.5 at screening.
Who cannot join
- CD19+ B cell count < 80 cells/µL at Screening, or < 40 cells/µL if B-cell depleting therapy was received within 24 weeks to 2 years prior.
- Diagnosis of paroxysmal nocturnal hemoglobinuria, Evan's Syndrome, or other bleeding disorders affecting safety or data integrity.
- Prior B-cell depleting therapy (e.g., rituximab) within 24 weeks before first dose or planned during the study.
- Chronic use of anticoagulants or antiplatelet agents (e.g., aspirin, NSAIDs, thienopyridines) within 14 days before dosing through follow-up. Intermittent NSAID use is allowed.
- Immunosuppressants (excluding corticosteroids) within 30 days or 5× half-life before Screening; alkylating agents within 180 days.
- IVIg treatment within 90 days prior to Screening.
Show all 9Show fewer
- Active ITP treatment (other than steroids or TPO agonists) within 30 days or 5× half-life before first dose, unless approved by Medical Monitor.
- Active, chronic, or latent infections including hepatitis B/C or HIV.
- Active TB or high TB risk.
Trial locations and contacts
20 sites in 5 countries. Contact the study team or a site near you to ask about taking part.
20 sites in 5 countries
Ukraine6 sites, 6 recruiting
- Not yet recruiting
Climb Bio Investigative Site #380208
Cherkasy
- Recruiting
Climb Investigative Site #380204
Ivano-Frankivsk
- Recruiting
Climb Investigative Site #2380203
Kyiv
- Recruiting
Climb Investigative Site #380202
Kyiv
- Recruiting
Climb Investigative Site #380206
Kyiv
- Recruiting
Climb Investigative Site #380201
Lviv
Greece4 sites, 4 recruiting
- Recruiting
Climb Bio Investigative Site #300204
Athens, Attica, 11527
- Recruiting
Climb Bio Investigative Site #300203
Chaïdári, Attica, 12462
- Recruiting
Climb Bio Investigative Site #300202
Ioannina, 45500
- Recruiting
Climb Bio Investigative Site #300201
Thessaloniki, 57010
Spain4 sites, 4 recruiting
- Not yet recruiting
Climb Bio Investigative Site #340206
Burgos, 9006
- Recruiting
Climb Bio Investigative Site #340204
Madrid, 28041
- Recruiting
Climb Bio Investigative Site #340202
San Pedro
- Recruiting
Climb Bio Investigative Site #340203
Valencia, 46010
Bulgaria3 sites, 3 recruiting
- Recruiting
Climb Bio Investigative Site #359202
Plovdiv, 4002
- Recruiting
Climb Bio Investigative Site #359203
Plovdiv, 4003
- Recruiting
Climb Bio Investigative Site #359201
Sofia, 1797
Serbia3 sites, 3 recruiting
- Recruiting
Climb Bio Investigative Site #381201
Belgrade
- Recruiting
Climb Bio Investigative Site #381202
Belgrade
- Recruiting
Climb Bio Investigative Site #381203
Novi Sad
About this study
Official title: A Phase 1b/2a, Open-Label, Sequential-Cohort, Dose Escalation and Expansion Study to Evaluate Safety, Tolerability, Pharmacokinetics, Pharmacodynamics, and Preliminary Clinical Effectiveness of Budoprutug (TNT119) in Subjects With Immune Thrombocytopenia (ITP)
The main objective is to assess the safety and tolerability of budoprutug in adults with ITP. Pharmacokinetics, pharmacodynamics, and preliminary clinical efficacy will also be assessed.
Read the detailed description
Budoprutug is a humanized, immunoglobulin (Ig) G1 monoclonal antibody that selectively binds to CD19 and is projected to deplete targeted cells through antibody-dependent cellular cytotoxicity. This Phase 1b/2a, open-label, sequential-cohort, dose escalation and expansion study will evaluate the safety, tolerability, PK, PD, and preliminary clinical effectiveness of budoprutug in subjects with ITP. Budoprutug will be administered as two (2) IV infusions 14 days apart in ascending dose cohorts of patients aged 18 years and above with a platelet count < 30,000/µL despite an adequate trial of at least one prior therapeutic attempt.
- Conditions
- Immune Thrombocytopenia (ITP), ITP, Biologics, Monoclonal, Anti-CD19
- Being tested
- Budoprutug
- Medical subject headings
- Purpura, Thrombocytopenic, Idiopathic
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
BudoprutugDrug
Also called TNT119
Single IV dose of study product on Day 1 and Day 15
| Study group | Role | What they receive |
|---|---|---|
| Cohort 1: Dose Level A | Experimental | Single IV dose of study product on Day 1 and on Day 15 Receives: Drug: Budoprutug |
| Cohort 2: Dose Level B | Experimental | Single IV dose of study product on Day 1 and on Day 15 Receives: Drug: Budoprutug |
| Cohort 3: Dose Level C | Experimental | Single IV dose of study product on Day 1 and on Day 15 Receives: Drug: Budoprutug |
| Dose Expansion Cohort | Experimental | Single IV dose of study product on Day 1 and Day 15 Receives: Drug: Budoprutug |
What is being measured
The primary outcome is the main question the study is designed to answer.
Incidence of Treatment-Emergent Adverse Events (TEAEs)
Number of participants experiencing TEAEs, graded per NCI CTCAE v5.0.
Measured: Up to week 48
Secondary outcomes (10)
Area Under the Curve (AUC)
Measurement of the area under the drug concentration-time curve.
Measured: Up to week 48
Maximum Observed Plasma Concentration (Cmax)
Measurement of the maximum observed plasma concentration.
Measured: Up to week 48
Time to Maximum Observed Concentration (Tmax)
Measurement of the time to maximum observed concentration.
Measured: Up to week 48
Terminal Half-Life (T1/2)
Measurement of the terminal half-life in days.
Measured: Up to week 48
Apparent Clearance (CL/F)
Measurement of the apparent clearance in L/hour.
Measured: Up to week 48
Change from Baseline in CD20+ B-cell Count
Change in absolute peripheral CD20+ B-cell count
Measured: Up to week 48
Change in Platelet Count
Change in platelet count over time
Measured: Up to week 48
Proportion of Participants with stable, partial or complete platelet response
Percentage of participants with stable, partial or complete platelet response.
Measured: Up to week 48
Incidence of Anti-Drug Antibodies (ADAs)
Number of participants with detectable ADAs.
Measured: Up to week 48
Steroid Discontinuation Rate
% of baseline steroid users who discontinue steroids.
Measured: Up to week 48
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted29 Jun 2025
- Study start30 Jun 2025
- Primary completionAug 2027 (estimated)
- Study completionAug 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Immune Thrombocytopenia (ITP)Studies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 1/2
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Sequential
- Model description
- This is an open-label study in which subjects will be enrolled into three dose ascending cohorts. Each subject's participation will last approximately 51 weeks including the Screening and Qualifying Visits (up to 3 weeks), Treatment Period (2 weeks), and follow-up visits though Week 48. Following completion of the dose escalation phase, additional subjects will be enrolled into an expansion cohort at the selected dose level(s) identified in Part 1b.
- Masking
- None (open label)
- Enrolment
- 24 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Climb Bio, Inc.
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Study Director, Study director, Climb Bio, Inc.
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07043946
- Sponsor's protocol ID
- TNT119-ITP-201
- Status last verified
- Mar 2026
- First submitted
- 20 Jun 2025
- Last updated
- 27 Mar 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 27 Mar 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Phase 1b/2a, Open-Label, Sequential-Cohort, Dose Escalation and Expansion Study to Evaluate Safety, Tolerability, Pharmacokinetics, Pharmacodynamics, and Preliminary Clinical Effectiveness of Budoprutug (TNT119) in Subjects With Immune Thrombocytopenia (ITP)
- ClinicalTrials.gov ID
- NCT07043946
- Acronym / sponsor ID
- TNT119-ITP-201
- Conditions
- Immune Thrombocytopenia (ITP), ITP, Biologics, Monoclonal, Anti-CD19
- Phase
- Phase 1/2
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 24 participants (estimated)
- Lead sponsor
- Climb Bio, Inc.Industry (pharma, biotech, devices)
- Study start
- 30 Jun 2025 (actual)
- Primary completion
- Aug 2027 (estimated)
- Study completion
- Aug 2028 (estimated)
- First posted
- 29 Jun 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The main objective is to assess the safety and tolerability of budoprutug in adults with ITP. Pharmacokinetics, pharmacodynamics, and preliminary clinical efficacy will also be assessed.
Detailed description
Budoprutug is a humanized, immunoglobulin (Ig) G1 monoclonal antibody that selectively binds to CD19 and is projected to deplete targeted cells through antibody-dependent cellular cytotoxicity. This Phase 1b/2a, open-label, sequential-cohort, dose escalation and expansion study will evaluate the safety, tolerability, PK, PD, and preliminary clinical effectiveness of budoprutug in subjects with ITP. Budoprutug will be administered as two (2) IV infusions 14 days apart in ascending dose cohorts of patients aged 18 years and above with a platelet count < 30,000/µL despite an adequate trial of at least one prior therapeutic attempt.
Study design
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Sequential
- Masking
- None (open label)
- Number of arms
- 4
- Model description
- This is an open-label study in which subjects will be enrolled into three dose ascending cohorts. Each subject's participation will last approximately 51 weeks including the Screening and Qualifying Visits (up to 3 weeks), Treatment Period (2 weeks), and follow-up visits though Week 48. Following completion of the dose escalation phase, additional subjects will be enrolled into an expansion cohort at the selected dose level(s) identified in Part 1b.
| Arm | Type | Receives |
|---|---|---|
| Cohort 1: Dose Level A | Experimental | Drug: BudoprutugSingle IV dose of study product on Day 1 and on Day 15 |
| Cohort 2: Dose Level B | Experimental | Drug: BudoprutugSingle IV dose of study product on Day 1 and on Day 15 |
| Cohort 3: Dose Level C | Experimental | Drug: BudoprutugSingle IV dose of study product on Day 1 and on Day 15 |
| Dose Expansion Cohort | Experimental | Drug: BudoprutugSingle IV dose of study product on Day 1 and Day 15 |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (3 listed)
- Aged 18 years at the time of consent.
- Platelet count < 30,000/µL despite an adequate trial of at least one prior therapeutic attempt. Platelet counts of < 30,000/µL must be confirmed on 2 occasions at least 5 days apart, but no more than 14 days apart.
- Partial thromboplastin time < 1.5 x upper limit of normal (ULN), prothrombin time < 1.5 x ULN, total bilirubin < 1.5 x ULN unless due to Gilbert's syndrome, or an international normalized ratio < 1.5 at screening.
Key exclusion criteria (9 listed)
- CD19+ B cell count < 80 cells/µL at Screening, or < 40 cells/µL if B-cell depleting therapy was received within 24 weeks to 2 years prior.
- Diagnosis of paroxysmal nocturnal hemoglobinuria, Evan's Syndrome, or other bleeding disorders affecting safety or data integrity.
- Prior B-cell depleting therapy (e.g., rituximab) within 24 weeks before first dose or planned during the study.
- Chronic use of anticoagulants or antiplatelet agents (e.g., aspirin, NSAIDs, thienopyridines) within 14 days before dosing through follow-up. Intermittent NSAID use is allowed.
- Immunosuppressants (excluding corticosteroids) within 30 days or 5× half-life before Screening; alkylating agents within 180 days.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| BudoprutugAlso: TNT119Single IV dose of study product on Day 1 and Day 15 | Drug | Cohort 1: Dose Level A, Cohort 2: Dose Level B, Cohort 3: Dose Level C, Dose Expansion Cohort |
Primary outcome
Incidence of Treatment-Emergent Adverse Events (TEAEs)
Time frame: Up to week 48
Number of participants experiencing TEAEs, graded per NCI CTCAE v5.0.
10 secondary outcomes
Area Under the Curve (AUC)
Time frame: Up to week 48
Maximum Observed Plasma Concentration (Cmax)
Time frame: Up to week 48
Time to Maximum Observed Concentration (Tmax)
Time frame: Up to week 48
Terminal Half-Life (T1/2)
Time frame: Up to week 48
Apparent Clearance (CL/F)
Time frame: Up to week 48
Change from Baseline in CD20+ B-cell Count
Time frame: Up to week 48
Change in Platelet Count
Time frame: Up to week 48
Proportion of Participants with stable, partial or complete platelet response
Time frame: Up to week 48
Incidence of Anti-Drug Antibodies (ADAs)
Time frame: Up to week 48
Steroid Discontinuation Rate
Time frame: Up to week 48
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 27 Mar 2026.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Study Director study director
Climb Bio, Inc.
20 sites in 5 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 1/2 study testing Budoprutug in people with Immune Thrombocytopenia (ITP) and ITP, run by Climb Bio, Inc. at 20 sites in 5 countries.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 9 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 27 Mar 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 20 sites in Ukraine, Greece, Spain, Bulgaria, Serbia. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this combined phase mean?
Phase 1 studies test a treatment in a small group of people for the first time or in a new way, mainly to check safety and find the right dose.
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Climb Bio Study Director (+1 866 857 2596, clinicaltrials@climbbio.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Incidence of Treatment-Emergent Adverse Events (TEAEs) (time frame: Up to week 48). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 27 Mar 2026.