NCT07623200 · Incyte Corporation
A Phase 3 Study of INCA033989 Versus Best Available Therapy in Participants With Essential Thrombocythemia
(EXCALIBUR-ET2)
What this study is about
This study is being conducted to evaluate INCA033989 versus best available therapy in participants with essential thrombocythemia and a CALR mutation previously treated with cytoreductive therapy.
View original scientific description
This study is being conducted to evaluate INCA033989 versus best available therapy in participants with essential thrombocythemia and a CALR mutation previously treated with cytoreductive therapy.
Interventions
DRUG
INCA033989
Administered intravenous (IV) in accordance with the protocol-defined requirements.
DRUG
Best Available Treatment
Best Available Therapy (BAT) will be selected by the investigator.
Primary outcome measures
Durable clinicohematologic response (DCR)
Time frame: Week 24
Normalization of platelet and white blood cell (WBC) counts and absence of disease progression as defined in the protocol.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Confirmed diagnosis of high-risk ET.
- Presence of mutCALR.
- Prior treatment with at least 1 cytoreductive therapy.
Exclusion criteria
- Presence of any hematologic malignancy other than ET.
- Major bleeding or thrombosis within the last 3 months prior to study enrollment.
- Any prior allogenic or autologous stem-cell transplantation.
- Unresolved toxicity ≥ Grade 2 from previous therapy except for stable chronic toxicities (Grade 2) not expected to resolve, such as stable Grade 2 peripheral neuropathy.
- Prior nonhematologic malignancy except for the following: Malignancy treated with curative intent and with no evidence of active disease for more than 2 years before screening. Adequately treated carcinoma in situ without current evidence of disease. Other protocol-defined Inclusion/Exclusion Criteria apply.
Where
- Gilbert, Arizona
- Tucson, Arizona
- Duarte, California
- Greenbrae, California
- Los Angeles, California
- Palo Alto, California
- San Francisco, California
- Lone Tree, Colorado
- Washington D.C., District of Columbia
- Fort Myers, Florida
- Miami, Florida
- Weston, Florida
And 27 more locations — see the full list below.
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Aug 6, 2026 · Source of record for eligibility and locations