Mosunetuzumab Consolidation Therapy After autoSCT in r/r Aggressive B Cell Lymphoma

This study is testing whether mosunetuzumab — a drug that helps the immune system attack lymphoma cells — given after a stem cell transplant can help prevent relapsed or treatment-resistant aggressive B-cell lymphoma from coming back. **You may be eligible if...** - You are 18 or older - You have been diagnosed with relapsed or refractory aggressive B-cell lymphoma (including large B-cell lymphoma, follicular lymphoma grade 3B, or similar types) - You are planning to undergo an autologous stem cell transplant (using your own cells) after receiving two or more prior treatment regimens - Your general health is good (ECOG score 0–2) **You may NOT be eligible if...** - You have not had a stem cell transplant - You are pregnant or unwilling to use contraception - You have certain active infections or other serious health conditions Talk to your doctor to see if this trial is right for you.