A First-in-Human, Open-Label, Multi-Center Phase 1 Study of TST003 in Subjects with Locally Advanced or Metastatic Solid Tumors

TST003 is a GREM1 monoclonal antibody

In this study, the sponsor and investigators want to learn:

• How much of the study agent can be given with an acceptable level of side effects
• The effects of the study agent (good and bad)
• How much of the study agent is absorbed into the blood and how fast it is removed
• How the study agent is acting on your body

During part 1, dose escalation, the amount of the study agent given will be increased in each group of research participants, to find the most appropriate dose for further study.

During part 2 of the study, a larger number of people receive the study drug dose determined to be appropriate in the dose escalation part of the study.

The dose of the study agent you receive will be determined based on when you enter the study.

The study regimen will be given in cycles.  Each cycle is 21 days (3 weeks).  You will receive the study agent once every 3 weeks as an IV infusion into a vein over 60-90 minutes.