Evaluate the Safety, Tolerability, and Efficacy of ICP-490 in Patients With Relapsed and/or Refractory Multiple Myeloma

This study is testing a new drug called ICP-490 for patients with multiple myeloma (a blood cancer affecting plasma cells in the bone marrow) that has come back or stopped responding to previous treatments. This is an early-phase trial assessing how safe the drug is and whether it works. **You may be eligible if...** - You are 18 or older with confirmed relapsed or refractory multiple myeloma - Your cancer is measurable on standard tests - You are in reasonably good health (ECOG score 0-2) - Your organ function (liver, kidneys, blood counts) is adequate - Your expected survival is at least 6 months **You may NOT be eligible if...** - You have multiple myeloma that has spread to the central nervous system - You have a type of plasma cell disease other than typical myeloma (e.g., plasma cell leukemia, POEMS syndrome, or amyloidosis) - You have had another active cancer within the past 5 years (except locally cured cancers) - You have significant heart disease or an active infection - You had major surgery within 28 days before starting treatment Talk to your doctor to see if this trial is right for you.