Development and preclinical evaluation of ovNDV-28: a chimeric Newcastle disease virus expressing human IL-2 for cancer therapy.

Newcastle disease virus (NDV) is a promising oncolytic virus, yet requires further optimization. In this study, we engineered an F-gene-chimeric NDV expressing human Interleukin 2 (hIL-2) to enhance the oncolytic efficacy of the NDV Clone30 strain. This recombinant virus, designated ovNDV-28, was then produced in suspension-cultured HEK293 cells. The therapeutic potential of ovNDV-28 was evaluated across multiple cancer cell lines, as well as in the HuH-7 xenograft and B16-F0 syngeneic models. Both in vitro and in vivo results demonstrated that ovNDV-28 significantly improved tumor growth suppression compared to the wild-type NDV. Flow cytometry revealed notable increases in tumor-infiltrating CD3⁺CD4⁺ T cells, CD3⁺CD8⁺ T cells, and CD3⁻CD49b⁺ cells, along with elevated expression levels of IFN-γ, TNF-α, perforin, and Granzyme B within tumor tissue. Comprehensive toxicological assessments conducted on B16-F0 tumor-bearing mice involved intratumoral administration of ovNDV-28 at doses of 1.12 × 10⁶ or 1.46 × 10⁷ PFU/mouse every other day for 14 days. No ovNDV-28-related biochemical, hematological, or histopathological abnormalities were observed. The virus was detected in tumor tissue, mesenteric lymph nodes, abdominal adipose tissue, brain, and biceps femoris, without evidence of blood circulation or viral shedding. This study systematically demonstrates the efficacy, safety, and pharmacokinetics of ovNDV-28, supporting its potential for clinical translation.