Anti-GD2 ADC M3554 in Advanced Solid Tumors

This trial is testing a new antibody-drug conjugate (ADC) called M3554, which targets a protein called GD2 found on certain cancer cells, in people with advanced soft tissue sarcoma or glioblastoma (a type of brain cancer) that has not responded to prior treatments. **You may be eligible if...** - You have advanced soft tissue sarcoma that has progressed after at least one prior line of chemotherapy containing anthracycline drugs, OR - You have glioblastoma that has progressed after one prior treatment (radiation plus/minus chemotherapy) and it has been at least 3 months since radiation - Your general health and organ function meet protocol requirements (ECOG 0-1) **You may NOT be eligible if...** - You have had another cancer in the past 3 years (with some exceptions) - You have brain or spinal cord metastases (for the soft tissue sarcoma group) Talk to your doctor to see if this trial is right for you.