Circular RNA (circRNA) is not a new concept, but it is a novel strategy in the field of gene and cell therapy. While mRNA vaccines have revolutionized medicine, this RNA fragment without free ends surpasses their performance in both efficacy and durability, bringing it to the attention of several pioneering companies. The latest advances in circRNA presented at the 29th Annual Meeting of the American Society of Gene and Cell Therapy (ASGCT) clearly surpass the performance achieved with linear mRNA.

Pheast Therapeutics Inc. has presented preclinical data on PHST-677, a novel bispecific antibody-drug conjugate (ADC) targeting E-cadherin (CDH1) and Nectin-4.

HEC Pharma Co. Ltd. recently presented HEC-201625, a small-molecule PD-L1 inhibitor for cancer immunotherapy that blocks the PD-1/PD-L1 signaling pathway. HEC-201625 was tested in vitro and in vivo in MC38 syngeneic murine model, as well as in xenograft A375 and NCI-H358 models.

A new mRNA and lipid nanoparticle (mRNA-LNP) platform could selectively reprogram in vivo cytotoxic effector T cells (Teff), the cells responsible for eliminating infected or tumor cells. To achieve this, scientists at the University of Pennsylvania conjugated LNPs with fractalkine, a molecule that binds to the CX3CR1 receptor, which is a marker of Teff cells. Using this strategy, the researchers delivered an mRNA encoding new proteins such as IL‑2 or human CD62 L‑selectin, opening the door to temporarily reprogramming these cells within the body, both in the blood and in lymphoid tissue, where they reside and become activated.

Researchers from Takeda Pharmaceutical Co. Ltd. detailed the preclinical characterization of TAK-188, a first-in-class anti-CCR8 antibody-drug conjugate (ADC) designed to selectively target CCR8+ Tregs, alleviating immunosuppression in the tumor microenvironment.

Biolojic Design Ltd. has reported preclinical data for its antibody-drug conjugate (ADC) BD-200, developed using an AI-guided antibody engineering platform named Multibody.