T Cell Lymphoma -Stratified Therapy After Response to First-line Treatment-NR

This study is evaluating new treatment strategies for patients with a rare and aggressive blood cancer called peripheral T-cell lymphoma (PTCL) whose disease did not respond to — or came back during — their first round of standard chemotherapy. **You may be eligible if...** - You are between 18 and 70 years old - You have a confirmed diagnosis of PTCL (specifically PTCL-NOS, ALK-negative ALCL, or follicular helper T-cell lymphoma) - Your cancer either did not respond to, or progressed during, at least 4 cycles of standard chemotherapy (CHOP or similar) - You have good physical function (ECOG 0 or 1) and adequate heart, lung, kidney, and liver function - A suitable stem cell donor has been identified for potential transplant **You may NOT be eligible if...** - You have stage I disease (early, limited-spread lymphoma) - You have had another cancer in the past 5 years (except certain fully treated skin cancers or early-stage cancers) - You have active tuberculosis, HIV, active hepatitis B or C, or another active viral infection - You have significant heart failure or recent heart attack - You are pregnant or breastfeeding - You have PTCL with involvement of the central nervous system (brain or spinal cord) - You have previously received PD-1/PD-L1 immunotherapy Talk to your doctor to see if this trial is right for you.