A Study of CRD3874-SI in People With Solid Tumors

This early-phase trial tests CRD3874-SI, a new experimental drug, in people with advanced solid tumors (various cancer types) that have not responded to standard treatments, with a focus on understanding safe doses and initial effectiveness. **You may be eligible if...** - You are 18 or older with a locally advanced or metastatic solid tumor that has progressed on at least one prior standard therapy - You are in reasonably good health (ECOG 0–1) with a life expectancy of at least 3 months - Your tumor has measurable disease - In the expansion phase: you have specific tumor types including sarcomas (UPS/MFS, angiosarcoma, bone sarcoma) or Merkel cell carcinoma that has progressed on prior immunotherapy **You may NOT be eligible if...** - You have had major surgery, active infection, or certain cardiovascular events recently - You are pregnant, breastfeeding, or not using contraception - You have significant kidney, liver, or bone marrow dysfunction - You are allergic to any component of the study drug Talk to your doctor to see if this trial is right for you.