Allogeneic B7-H3-Targeted CAR Vδ1T-cell Therapy in Advanced Solid Tumors: A Phase I Study

Area of Science:

• Oncology
• Immunotherapy
• Cell Therapy

Background:

• Advanced solid tumors often lack effective treatment options.
• Chimeric antigen receptor (CAR)-T cell therapy shows promise but faces challenges with allogeneic (
• Purpose_of_the_Study
• Main_Methods
• Main_Results
• Conclusions

Purpose of the Study:

• Evaluate the safety, pharmacokinetics, and preliminary clinical activity of UTAA06, an allogeneic B7-H3-targeted CAR-Vδ1T cell therapy.
• Assess UTAA06 in patients with pretreated, advanced B7-H3-positive solid tumors.

Main Methods:

• Phase I, dose-escalation study (NCT06372236) enrolling ten patients with advanced solid tumors.
• Patients received UTAA06 after lymphodepletion chemotherapy across three dose levels.
• Primary endpoint was safety; secondary endpoints included pharmacokinetics and anti-tumor efficacy.

Main Results:

• UTAA06 exhibited a manageable safety profile with no graft-versus-host disease (GvHD) and limited Grade 1 cytokine release syndrome (CRS).
• One dose-limiting toxicity (Grade 3 pneumonitis) occurred at the lowest dose.
• Biological activity was observed, including transient tumor marker reductions, but no objective responses by RECIST criteria.

Conclusions:

• Allogeneic B7-H3-targeted CAR-Vδ1T cells represent a safe platform with low GvHD risk and biological activity in solid tumors.
• Clinical efficacy was limited by reduced CAR-T cell persistence due to host immune rejection.
• Future strategies must enhance cellular persistence to improve the therapeutic potential of this allogeneic approach.