A Study of BL-B16D1 in Patients With Recurrent or Metastatic Head and Neck Squamous Cell Carcinoma and Other Solid Tumors

This early-phase study is testing a new drug called BL-B16D1 in people with head and neck squamous cell carcinoma or other solid tumors that have come back or spread after standard treatments have stopped working. **You may be eligible if...** - You are 18 to 75 years old (Phase Ia) or 18 and older (Phase Ib) - You have confirmed recurrent or metastatic head and neck squamous cell carcinoma or another solid tumor - You have already tried standard treatments and they no longer work - You have at least one measurable tumor on a scan - Your ECOG performance score is 0 or 1 (fully active or restricted only in strenuous activity) - Your expected survival is at least 3 months **You may NOT be eligible if...** - Your overall health status is too poor for trial participation - You have serious heart, liver, or kidney problems - Previous treatment side effects have not resolved - You are pregnant or breastfeeding Talk to your doctor to see if this trial is right for you.