In AML, a CAR T cell’s target can determine whether treatment attacks leukemia while sparing healthy blood-forming tissue. The FDA has cleared a first-in-human study of CLEC2A-directed CAR T cells for adults and children with acute myeloid leukemia (AML).
That clearance permits clinical investigation. It does not authorize the therapy’s sale or show that it works in patients. The FDA’s public materials do not list CLEC2A CAR T as a licensed or approved therapy.
Patients will enroll at Fred Hutch Cancer Center. Seattle Children’s Hospital is another study site. The third is Children’s Hospital of Los Angeles. The trial will initially focus on KMT2A-rearranged and monosomy 7 AML, which the research team identifies as needing more effective treatment.
CAR T cells can also injure normal cells when the target antigen is shared between cancerous and healthy tissues, a recognized source of treatment-related toxicity.
The central test is target selectivity
The team describes CLEC2A as an AML-restricted antigen that is silent in normal hematopoiesis. The approach depends on CAR T cells recognizing leukemia while leaving normal blood-forming cells alone. A review in Clinical & Experimental Immunology discusses how antigen distribution across tumor and normal cells can contribute to CAR-T toxicities. The clinical study must test the selectivity claim directly, including whether the strong antileukemic activity seen in preclinical models holds up without on-target hematopoietic toxicity.
Preclinical activity gives researchers a reason to run the trial; it does not establish clinical benefit. This is the first clinical effort to target CLEC2A, which the team identified through its TpAML-supported proteo-genomic discovery program.
One of three AML-restricted CAR T programs
Soheil Meshinchi, Professor of Translational Science and Therapeutics at Fred Hutch, said CLEC2A is the second of three AML-restricted CAR T therapies his group is bringing toward clinical implementation. A FOLR1 CAR T trial is advancing to phase II after eight patients were treated. Meshinchi reported significant efficacy and said treatment was safe. A mesothelin CAR T trial is anticipated to activate in early 2027.
The available ClinicalTrials.gov results did not independently confirm a CLEC2A CAR T trial registration, patient enrollment, first dosing, or clinical results. This lack of confirmation does not establish that the study has not begun; it means those milestones could not be verified in the reviewed public results.
Danielle Kirkey is the CLEC2A study’s principal investigator. Meshinchi credited her leadership with taking the therapy from discovery to clinical readiness in four years. He identified Dr. Wei Li at the University of Pittsburgh as the developer of the fully human antibody used as the CAR’s binder.
Researchers are also testing distinct CAR T targets in other diseases. An ovarian cancer trial reported stable disease in one patient. That result does not establish what CLEC2A-directed cells may do in AML.
Meshinchi said Fred Hutch and Professor Franco Locatelli’s team at Ospedale Pediatrico Bambino Gesù (OPBG) in Rome are advancing the three programs along parallel clinical paths. For CLEC2A, the Rome team is developing a retroviral construct with the same antibody binder and anticipates trial activation in early 2027. The centers are coordinating protocol development and scientific work to support studies in the United States and Europe.
