BOXR1030 T Cells in Subjects With Advanced GPC3-Positive Solid Tumors

This is a FIH, Phase 1/2, open-label, multicenter study to assess safety and determine the maximum tolerated dose (MTD) and/or RP2D of BOXR1030 administration after LD chemotherapy in subjects with GPC3+ advanced solid tumors. After signing informed consent and completing all screening assessments, eligible subjects will be enrolled and undergo leukapheresis to obtain T cells for BOXR1030 manufacturing. Subjects will receive a 3-day LD chemotherapy regimen with fludarabine and cyclophosphamide, administered according to institutional standard practice for these drugs, including inpatient administration as appropriate. Subjects must be hospitalized for BOXR1030 administration and will remain hospitalized for 10 days after the infusion. For 28 days after BOXR1030 administration, all subjects must stay within a distance that requires no more than 2 hours of travel to the study site. During the Post-treatment Evaluation Period (within 6 months after BOXR1030 administration), study visits will occur daily for the first week, twice in the second week, and then once weekly at Weeks 3, 4, 6, 9, 12, 15, 18, and 24. Safety (targeted physical examination, adverse event \[AE\] assessment, and clinical laboratory tests) will be evaluated and samples will be collected for endpoint analyses. For 28 days after BOXR1030 administration, subjects will be required to monitor their temperature and complete neurological evaluation via the immune effector cell-associated encephalopathy assessment tool every day (to be administered by site staff during clinical visits and by a caregiver at home on non-clinic days). At regular intervals, antitumor activity will be assessed per RECIST 1.1 and iRECIST criteria. After 6 months of follow-up from BOXR1030 administration, subjects will enter the Long-term Follow-up Period for a total duration of 15 years after BOXR1030 dosing. Study visits are scheduled at Months 7, 9, 11, 13, 15, 18, 21, and 24, every 6 months thereafter until Year 5, and then annually through Year 15. Long-term follow-up assessments will focus on long-term safety and disease status. Subjects whose disease does not progress before Week 24 will enter the Long-term Follow-up at Month 7. Survival status will be checked at these visits.