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A Phase 3, Open-Label, Multicenter, Randomized, Active-controlled Study to Assess Pharmacokinetics and Compare the Efficacy, Safety, and Tolerability of P1101 vs Anagrelide as Second Line Therapy for Essential Thrombocythemia

Clinical Trial Details

The purpose of this study is to compare the effect of the P1101 with Anagrelide on you and your Essential Thrombocythemia (ET) to see which is better.

This research study is being done because participants with uncontrolled ET are at higher risk of thrombosis (clotting of the blood) and hemorrhage (heavy bleeding). As the disease worsens, the size of the spleen (an organ in your stomach area that produces and removes blood cells) and liver increases in most cases, and the bone marrow (a semi-solid substance found in bones that produces blood cells) shows signs of fibrosis (a thickening). The goal of P1101 is to reduce the risk of thrombosis and bleeding and to slow disease progression. In addition, this study is looking at the effectiveness of long-term therapy on whether the drug is safe or not.

Key Eligibility: 
  • 18 Years and older
  • Subjects diagnosed with high-risk ET
  • Interferon treatment-naïve
  • Documented resistance/intolerance to prior hydroxyurea for ET

Detailed eligibility will be reviewed when you contact the study team.

Study contact by location

Upper East Side - Manhattan


Niamh Savage
(917) 514-7578

Primary Investigator(s)

Protocol ID(s)

Weill Cornell Medicine IRB #:




Open to Enrollment

Age Group