We are doing this study to find out if an experimental drug called cema-cel is a safe and effective option for patients with large B-cell lymphoma. Cema-cel is a CAR T Cell therapy that is made from your own white blood cells. We also want to compare how well cema-cel works when it is given with and without another experimental drug called ALLO-647.

Large B-cell Lymphoma

Adults ages 18+ who:

• Are diagnosed with large B-cell lymphoma; AND
• Have achieved a clinical response or partial response from previous treatment that makes them suitable for observation

For more information about who can join this study, please contact the study team at quinna.marshburn@duke.edu.

If you choose to join this study, you will go through a screening period that lasts around 28 days to see if you are eligible to take part. If you are eligible, you will proceed to the study period.

During the study period, you will get a random assignment (like a coin flip) to 1 of 2 groups:

• One group will take a regimen that uses cema-cell
• The other group will not receive any treatment and will continue to have their health and condition monitored by their doctor(s)

If you are assigned to get the study drug, you will get another random assignment:

• You will either get a drug regimen that involves lymphodepletion with fludarabine, cyclophosphamide, and ALLO-647 followed by getting a dose of cema-cel; OR
• You will get a drug regimen that involves lymphodepletion with only fludarabine and cyclophosphamide followed by getting a dose of cema-cel