Recruiting
Phase 1
Phase 2

Pirtobrutinib

Sponsor:

Eli Lilly and Company

Code:

NCT06721013

Conditions

Immune Thrombocytopenia (ITP)

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

Interventions

Pirtobrutinib

Placebo

Study Details

Brief summary:

The purpose of the phase 1 part of this study was to evaluate how well pirtobrutinib is tolerated and what side effects may occur. The phase 2 part of the study will further investigate efficacy and safety of multiple pirtobrutinib dosages versus placebo.

The study drug will be administered orally in participants with Primary Immune Thrombocytopenia (ITP). Blood tests will be performed to check how much pirtobrutinib gets into the bloodstream and how long it takes the body to eliminate it.

The study will last up to approximately 16 weeks for phase 1 dose-escalation and 28 weeks for phase 2 dose-optimization, excluding screening.

Conditions

Immune Thrombocytopenia (ITP)

Study ID

NCT06721013

Start date

Jul 30, 2025

Status verified date

Jun, 2026

Completion date

May, 2029

Anticipated

Primary completion date

May, 2028

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

Inclusion Criteria:

  • Have a diagnosis of primary ITP, defined as isolated thrombocytopenia not associated with another known disease process
  • Have documented history of response, defined as 2 or more platelet counts greater than or equal to 50,000/microliter (μL), to at least 1 prior line of therapy. Splenectomy is considered a line of therapy
  • Have relapsed or treatment-resistant primary ITP, with no available therapies known to provide clinical benefit
  • Have a platelet count less than 30,000/μL on 2 occasions at least 5 days apart in the 15 days before randomization
  • Have adequate liver, renal, and hematologic functions as defined by a table
  • Are willing to follow contraception requirements

Exclusion Criteria:

  • Have a history of any thrombotic or embolic event within 12 months before screening
  • Had a transfusion with blood or blood products or plasmapheresis within 14 days (Phase 1) or within 28 days (Phase 2) of randomization
  • Have significant cardiovascular disease
  • Have a diagnosis or history of hematologic malignancy
  • Have hepatitis B virus (HBV) defined as positive for antigen of hepatitis B (HBsAg) or polymerase chain reaction (PCR) positive for HBV deoxyribonucleic acid (DNA)
  • Have hepatitis C virus (HCV) defined as positive for anti-HCV antibodies and PCR positive for HCV ribonucleic acid (RNA)

Study Design

Enrollment

68 participants

Anticipated

Allocation

Randomized

Intervention Model

Sequential

Primary purpose

Basic Science

Interventions and Outcome Measures

Arms

experimental: Pirtobrutinib Phase 1

Pirtobrutinib administered orally

experimental: Pirtobrutinib Phase 2

Pirtobrutinib administered orally

placebo comparator: Placebo Phase 2

Placebo administered orally

Interventions

Pirtobrutinib

Administered orally

Placebo

Administered orally

Primary outcome measure

  • Phase 1-Number of Participants with One or More Treatment Emergent Adverse Events (TEAEs) and Serious Adverse Event(s) (SAEs) Considered by the Investigator to be Related to Study Drug Administration [ Time Frame: Baseline Up to Week 4 ]
  • Phase 1-Dose Limiting Toxicity (DLT) of Pirtobrutinib [ Time Frame: Baseline Up to Week 4 ]
  • Phase 1-Number of Participants with Treatment-Related Adverse Events as Assessed by Vital Signs: Blood Pressure, Pulse Rate, and Body Temperature [ Time Frame: Baseline Up to Week 16 ]
  • Phase 1-Number of Participants with Treatment-Related Adverse Events as Assessed by Clinical Lab Tests: Hematology, Clinical Chemistry, Urinalysis, Pregnancy, Hepatitis Serology and Cytomegalovirus (CMV) [ Time Frame: Baseline Up to Week 16 ]
  • Phase 1-Number of Participants with Treatment-Related Adverse Events as Assessed by Electrocardiograms (ECGs): ECG QT Interval [ Time Frame: Baseline Up to Week 16 ]
  • Phase 2-Efficacy of Pirtobrutinib Versus Placebo [ Time Frame: Baseline Up to Week 24 ]

Central Contacts and Locations

Central contacts

Trial questions or participation questions: 1-877-CTLILLY (1-877-285-4559) or

1-317-615-4559LillyTrials@Lilly.com

Physicians interested in becoming principal investigators please contact

clinical_inquiry_hub@lilly.com

Locations

USC Norris Comprehensive Cancer Center

Recruiting

Los Angeles, California, United States, 90033

MedStar Georgetown University Hospital

Recruiting

Washington D.C., District of Columbia, United States, 20007

Ochsner Clinic Foundation

Recruiting

New Orleans, Louisiana, United States, 70121

Clinical Research Alliance

Recruiting

Westbury, New York, United States, 11590

MD Anderson Cancer Center

Recruiting

Houston, Texas, United States, 77030

More Information

Sponsor

Eli Lilly and Company

Last update posted

Jun 25, 2026

Last verified

Jun, 2026

Keywords

  • Primary ITP

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-09. This information was provided to ClinicalTrials.gov by Eli Lilly and Company on 2026-06-25.