A Phase 3 Study of INCA033989 Versus Best Available Therapy in Participants With Essential Thrombocythemia

Open to people ages 18 years and up

• Confirmed diagnosis of high-risk ET.
• Presence of mutCALR.
• Prior treatment with at least 1 cytoreductive therapy.

• 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.