T-MAXIMUM Biopharmaceuticals (Suzhou) Co., Ltd.

The clinical protocol plans to preset three dose groups, namely 1×10⁷ cells per dose, 3×10⁷ cells per dose, and 6×10⁷ cells per dose. The injection will be administered once every three weeks, adopting a "3 + 3" dose escalation design. The dosing interval is based on the pharmacokinetic (PK), safety and preliminary efficacy data of MT027 investigator-initiated trial (IIT) previously conducted at Dushu Lake Hospital of Soochow University. Accordingly, it is recommended to maintain the dosing interval of once every three weeks, with a window period of ±7 days. According to past experience, the dosing cycle should be at least 6 cycles, with each cycle lasting 21 days. If patients still benefit after more than 6 cycles, they can continue to receive the medication until no further benefit is achieved. The number of treatment sessions is approximately 6 to 9 times. However, the specific number of treatment sessions will generally be determined by the investigator based on the patient's disease condition.

MT027 is an off-the-shelf, allogeneic chimeric antigen receptor T cell (UCAR-T) injection prepared from healthy donor T cells targeting B7-H3. It is a next-generation, ready-to-use CAR-T product that can be used immediately and promptly for patients to solve the problem of unmet medical needs for a large number of patients who have a demand for CAR-T therapy but cannot receive it due to the common reasons of long production cycle, insufficient production capacity, and incompatibility of patients' T cells with the production conditions. In addition, the expected medical cost of allogeneic CAR-T cells is significantly lower, which can greatly alleviate the economic burden on patients.
MT027 is prepared by expressing a chimeric antigen receptor (CAR) targeting B7H3 on gene-edited T cells through gene modification technology. MT027 products targeting the B7H3 target developed by Moxing Biotech avoid the potential graft-versus-host disease (GvHD) and host anti-graft reaction (HvGR) caused by the interaction between exogenous T cells and the patient's immune system, and have shown good safety and efficacy in recurrent high-grade glioma in the initial phase.

This is a phase I open label, single-arm, dose-escalation study to evaluate the feasibility, safety, tolerability, PK/PD, and to determine RP2D of MT027 via an locoregional delivery in subjects with pleural malignant tumors, who have previously received standard of care therapy..
Subjects meeting the study entry criteria including having tumor antigen B7H3 overexpression via immunohistochemistry (IHC ) will be enrolled and assigned to cohorts sequentially to receive study treatments, assessments, as well as post-treatment safety follow-ups in the study.