Updated data from alloSHRINK phase I first-in-human study evaluating CYAD-101, an innovative non-gene edited allogeneic CAR-T in mCRC.

Abstract

74 Background: CYAD-101 is a first-in-class, non-gene edited allogeneic CAR T-cell product that combines the broad breadth of tumor targeting of the NKG2D-based chimeric antigen receptor (CAR) with a peptide-based approach that controls graft versus host disease (GvHD). NKG2D binds eight ligands commonly over-expressed across many tumors while the co-expressed T-cell receptor (TCR) inhibitory (TIM) peptide interferes with signaling by the endogenous TCR. A bank of CYAD-101 cells was produced from a single donor and evaluated in the AlloSHRINK phase 1 study (NCT03692429) in patients with unresectable metastatic colorectal cancer (mCRC). Methods: Three CYAD-101 infusions, each administered following a FOLFOX standard cycle as preconditioning chemotherapy, were tested in a 3+3 dose-escalation study (dose-levels (DL): 108, 3x108 and 109 T-cells per infusion) in patients with relapsed/refractory mCRC who progressed after previous treatment with oxaliplatin-based chemotherapy, with or without irinotecan-based chemotherapy. Results: Fifteen patients (pts) were enrolled (3 pts at DL-1, 3 pts at DL-2, 9 pts at DL-3). No dose-limiting toxicity (DLT), Grade ≥ 3 related adverse events or GvHD were reported after any of the CYAD-101 infusions, thus confirming the overall good safety profile of CYAD-101 post FOLFOX. Encouraging anti-tumor activity was observed with 2 confirmed partial responses (PR), including one response in a KRAS mutated patient. In addition, 9 pts achieved stable disease (SD), with 7 SD lasting at least 3 months. The median progression-free survival in this heavily pre-treated population was 3.9 months (95% CI). Whilst engraftment of the CYAD-101 cells was observed after each infusion, the relative level of systemic cytokines appeared to be primarily modulated by cell dose with some suggestion that the magnitude of modulation might be associated with clinical response. Interestingly, preliminary analysis of the T-cell repertoire identified some evidence of TCR diversity after therapy in the patient showing the most durable partial response. Conclusions: These clinical results demonstrate the safety and tolerability of a fist-in-human non-gene edited allogeneic CAR T-cell treatment with early promising anti-tumor activity in advanced mCRC pts. Preliminary translational analysis present intriguing observations that the modulation of systemic cytokine levels may be associated with dose which is uncommon in CAR T-cell therapies reported to date while limited T-cell clonal diversification in the best responding patient underscores the likely central role of the adoptively transferred T-cell in driving therapeutic response in this particular patient. Extension cohort evaluating CYAD-101 following other preconditioning chemotherapy is expected to be initiated end 2020. Clinical trial information: NCT03692429.