N-803 in Patients With Progressive Synovial Sarcoma and Myxoid/Round Cell Liposarcoma Previously … (NCT07261657) | Clinical Trial Compass
RecruitingEarly Phase 1
N-803 in Patients With Progressive Synovial Sarcoma and Myxoid/Round Cell Liposarcoma Previously Treated With Adoptive Cellular Therapy
United States8 participantsStarted 2026-04-13
Plain-language summary
This early phase I trial tests the safety and how well N-803 works in treating patients with synovial sarcoma (SS) or myxoid/round cell liposarcoma (MRCL) that is growing, spreading, or getting worse (progressive) after being treated with adoptive cellular therapy (ACT) using T-cell receptor therapy (T-CRT). Synovial sarcoma is a rare, slow-growing cancer that affects the soft tissues, like muscles or ligaments near the joints. Myxoid/round cell liposarcoma is a rare type of soft tissue sarcoma cancer that originates from fat cells usually in the arms and legs. N-803 is a type of immunotherapy-a treatment that helps patients' own immune system fight cancer, and it is made up of a natural protein called interleukin-15 (IL-15) that is important for growing and activating immune cells. Studies have shown that patients can progress after initially responding to TCR-T, so this trial will use N-803 to stimulate rare persisting cells (cells that survive treatment and cause treatment failure and disease relapse) to make them work better at attacking the cancer. Adoptive cell therapy is a type of therapy that uses a patient's own immune cells to fight cancer. T-cell receptor therapy is a type of ACT that can recognize better recognize and bind to protein in cancer cells. Giving N-803 may be safe and tolerable in patients with SS or MRCL.
Who can participate
Age range
18 Years – 80 Years
Sex
ALL
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion Criteria:
* Patients must have histologically or cytologically confirmed Synovial Sarcoma (SS) and/or Myxoid/Round Cell Liposarcoma (MRCL) who have progressed after ACT using TCR-T.
* Patients must have been treated with a TCR-T product that can be assessed per medical history and/or discretion of the principal investigator. This includes the FDA approved Afamitresgene autoleucel but also other products at the discretion of the principal investigator.
Note on References to Letetresgene Autoleucel and Afamitresgene Autoleucel: This study does not involve active treatment with TCR-T cell therapies, including Letetresgene autoleucel or Afamitresgene autoleucel. The investigational drug of this study is N-803. Please see Section 4.3.3 for more information.
* Patients must have measurable disease according to RECIST v1.1. See Appendix A for RECIST v1.1 criteria.
* Patients must have shown clinical benefit on at least one scan post ACT using TCR-T, (SD, PR, CR), as determined by the treating investigator.
* Patients must be aged ≥ 18 to 80 at time of registration.
* Patients must have a performance status of \>70% on the Karnofsky Scale (see Appendix A) or \< 2 on the ECOG Performance Scale (see Appendix B).
* Patients must be able to undergo leukapheresis per institutional standards. For patients receiving leukapheresis at the Rube Walker Blood Center, see Appendix F for reference document guidance and Rube Walker Blood Center leukapheresis eligibility criteria.
* Pat…
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
What they're measuring
1
The expansion of rare persisting transferred T-cell receptor therapy
Timeframe: Before and after eight weeks of N-803 therapy
2
Incidence of adverse events
Timeframe: Up to 30 days after the last administration of N-803