N-803 in Patients With Progressive Synovial Sarcoma and Myxoid/RoundCell Liposarcoma Previously Treated With Adoptive Cellular Therapy
Trial ID: NCT07261657
Phase: Early Phase 1
Status: Recruiting
Last Update Posted: June 2026
Eligibility: Adults aged 18 to 80 with synovial sarcoma or myxoid/round cell liposarcoma who have previously received and progressed after T-cell receptor therapy (TCR-T), including FDA-approved afamitresgene autoleucel (Tecelra) or similar products targeting MAGE-A4, PRAME, or NY-ESO-1. Patients must have shown at least some clinical benefit on at least one scan after their prior T-cell therapy and have measurable disease.
Overview: This pilot Phase 1 trial tests N-803 (nogapendekin alfa inbakicept), an IL-15 superagonist, in patients whose synovial sarcoma has progressed after prior T-cell therapy. Even after T-cell therapy fails, rare tumor-specific T-cells can still be detected in the blood of synovial sarcoma patients. While these surviving T-cells are no longer able to expand or kill tumor effectively on their own, stimulating them with IL-15 may reactivate them into potent cancer-killing agents. N-803 is given by subcutaneous injection every 14 days for up to 52 cycles. Patients also undergo leukapheresis before and during treatment so that researchers can track whether the surviving T-cells are expanding and becoming active again.
Preliminary Effectiveness: N-803 is FDA-approved for bladder cancer, but this is the first trial ever designed to reactivate residual T-cells in synovial sarcoma patients after prior T-cell therapy. Laboratory results showed this to be a highly effective strategy, and this trial will now test whether those findings translate to the clinic. No clinical results have been posted to ClinicalTrials.gov at this time.
Study Contact: Seth M. Pollack, MD, Northwestern University
- Email: seth.pollack@northwestern.edu
- Phone: 312-695-6180
- General inquiries: cancer@northwestern.edu / 312-695-1301
Treatment Centers:
- Northwestern University, Chicago, IL