Adicet Bio, Inc. announced positive safety and efficacy data from the Company's ongoing Phase 1 study of ADI-001 for the potential treatment of relapsed or refractory B-cell NHL. The Company believes these data continue to support the potential of Adicet's investigational gamma delta CAR T cell therapy to provide significant benefit both in terms of anti-tumor activity and safety. Based on the study findings as of a December 5, 2022 data-cut date, Adicet plans to transition ADI-001 into a potentially pivotal program in the second quarter of 2023. Data highlights as of the December 5, 2022 data-cut date were as follows: Of the 16 evaluable patients, three received ADI-001 at dose level 1 (DL1) (30 million CAR+ cells), three received ADI-001 at DL2 (100 million CAR+ cells), three received ADI-001 at DL3 (300 million CAR+ cells), one received two infusions of ADI-001 at DL3 (2X 300 million CAR+ cells on day one and seven following a single lymphodepletion), and six received ADI-001 at DL4 (1 billion CAR+ cells).
• On an exploratory basis, primarily to understand safety and pharmacokinetics of a second ADI-001 dose, the first and second patient in DL3 while testing negative for minimal residual disease (MRD) and in CR, received a second DL3 dose, three and two months after the first infusion, respectively. Patients were heavily pretreated with a median number of prior therapies of four (range two-six) and had a poor prognostic outlook based on their median International Prognostic Index (IPI) score. ADI-001 treatment demonstrated a 75% ORR and 69% CR rate in the study across all dose levels. In five LBCL patients that previously relapsed after prior autologous anti-CD19 CAR T therapy, treatment with ADI-001 demonstrated 100% ORR and CR rate (5/5). These patients included a triple-hit high-grade B-cell lymphoma patient, three diffuse large B-cell lymphoma (DLBCL) patients, and a double-hit high-grade B-cell lymphoma patient. ADI-001 resulted in CR in patients who previously showed a partial response (PR) to autologous CAR T (2/2). An 86% CR rate (6/7) was observed in LBCL patients across DL3 and above. 75% CR rate (9/12) in LBCL across all dose levels. Both DL2 and DL3 demonstrated a six-month CR rate of 33%; Patient follow up continues in DL4 to assess six-month durability. Circulating ADI-001 cells were visible through day 28 in peripheral blood at DL4. ADI-001 was generally well-tolerated in the study to date. There were no occurrences of dose-limiting toxicities, graft vs host disease (GvHD), or Grade 3 or higher Cytokine Release Syndrome (CRS) or immune effector cell-associated neurotoxicity syndrome (ICANS) reported. ADI-001 is an investigational allogeneic gamma delta CAR T cell therapy being developed as a potential treatment for relapsed or refractory B-cell NHL. ADI-001 targets malignant B-cells via an anti-CD20 CAR and via the gamma delta innate and T cell endogenous cytotoxicity receptors. Gamma delta T cells engineered with an anti-CD20 CAR have demonstrated potent anti-tumor activity in preclinical models, leading to long-term control of tumor growth. In April 2022, ADI-001 was granted Fast Track Designation by the FDA for the potential treatment of relapsed or refractory B-cell NHL.