NCT06946225RecruitingPhase 1
ACTengine® IMA203 Combined With mRNA-4203
A First-in-human, Open-label Trial to Evaluate the Combination of ACTengine® IMA203 With mRNA-4203 in Previously Treated, Unresectable or Metastatic Cutaneous Melanoma or Synovial Sarcoma Patients (ACTengine® IMA203-102)
Source: ClinicalTrials.gov · Last updated 8 Jan 2026
Brief summary (registry, in English)
This purpose of this clinical trial is to evaluate the safety, tolerability and anti-tumor activity of IMA203 in combination with different doses of mRNA-4203. The trial includes participants with previously treated unresectable or metastatic cutaneous melanoma (CM) or synovial sarcoma (SS).
- Status (registry)
- Recruiting
- Phase (registry)
- Phase 1
- Study type
- Interventional
- Enrollment
- 15 (estimated)
- First submitted
- 19 Apr 2025
- Start date
- 25 Jul 2025
- Primary completion date
- Aug 2029
- Lead sponsor
- Immatics US, Inc.
- NCT number
- NCT06946225
What you commit to
- Study type: Interventional · Phase 1
- Planned participants: 15
- From 25 Jul 2025 to the primary completion date, Aug 2029
- 4 sites in 1 country
- Visits and tests: ask the trial team, the registry does not list them
Built from the registry fields of ClinicalTrials.gov. It describes the study, not your situation.
Who cannot take part
Copied verbatim from ClinicalTrials.gov and grouped by topic. Only the trial team decides who can take part.
Prior treatment
- Prior allogenic stem cell transplantation or solid organ transplantation
- Concurrent severe and/or uncontrolled medical disease that could compromise participation in the study
- Participants with active brain metastases prior to lymphodepletion
- Concurrent treatment in another clinical trial or a device trial that could interfere with the IMA203 treatment
Other illness
- History of other malignancies (except for adequately treated basal or squamous cell carcinoma or carcinoma in situ) within the last 3 years
- Serious autoimmune disease
- History of cardiac conditions as per protocol
- History of hypersensitivity to cyclophosphamide, fludarabine, or IL-2
- History of hypersensitivity to mRNA-based medicines
- Positive for HIV infection or with active hepatitis B virus (HBV) or active hepatitis C virus (HCV) infection
- Any condition contraindicating leukapheresis
- Participants with renal impairment AND reduced bone marrow reserve per protocol
- Other protocol defined exclusion criteria could apply
Other
- Pregnant or breastfeeding
- Participants with lactate dehydrogenase (LDH) greater than threshold allowed per protocol
Who the study is looking for
- Pathologically confirmed and documented cutaneous melanoma (CM) or synovial sarcoma (SS) with unresectable or metastatic disease
- HLA-A\*02:01 positive
- Adequate selected organ function per protocol
- Eastern Cooperative Oncology Group (ECOG) performance status 0-1
- Measurable disease according to Response Evaluation Criteria in Solid Tumors (RECIST 1.1)
- Life expectancy more than 5 months
- CM participants who must have disease progression (resistance, toxicity) on or after at least one PD-1 inhibitor
- SS participants must have received (or declined) at least one line of treatment (including SoC) and are still in need of further systemic therapy.
- Female participants of childbearing potential must use adequate contraception prior to trial entry until 12 months after the infusion of IMA203 and 15 days after the last mRNA 4203 dose administration
- Other protocol defined inclusion criteria could apply
Age in the registry: 18 years to - · Sex: All · Does not accept healthy volunteers
Sites (4)
Sites in registry order. Pick your city on the disease page to sort them by distance.
| Site | City | Country | Site status |
|---|---|---|---|
| Dana-Farber Cancer Institute Coordinator of this site? Confirm its status | Boston | United States | Recruiting |
| MD Anderson Cancer Center Coordinator of this site? Confirm its status | Houston | United States | Recruiting |
| Memorial Sloan-Kettering Cancer Center Coordinator of this site? Confirm its status | New York | United States | Recruiting |
| University of California San Francisco Coordinator of this site? Confirm its status | San Francisco | United States | Recruiting |
This page is information, not medical advice. Discuss any trial with your doctor.