A Study to Assess Safety and Efficacy of SOT106 in Patients With LRRC15-positive Advanced Unresectable or Metastatic Osteosarcoma or Soft Tissue Sarcoma

SOT106 is a special cancer medicine designed to find and kill certain cancer cells that carry a marker called LRRC15, while causing less harm to healthy cells. The study consists of two parts, Part A and Part B. The goal of Part A is to collect information about SOT106, understand its effects, and see whether it is safe and well tolerated at different dose levels. Part B of the study collects information on which of the two selected safe dose levels chosen in Part A gives the best balance between benefit and risk.