Xenetic Biosciences (XBIO) Status Update summary

DNase I platform overview and mechanism

• DNase I is being developed to target neutrophil extracellular traps (NETs), which are implicated in tumor progression, metastasis, and therapy resistance in cancer.

• NETs create an immunosuppressive tumor microenvironment and hinder immune cell access to tumor cells.

• Targeting NETs with DNase I aims to improve responses to chemotherapy, immunotherapy, and radiotherapy.

Recent preclinical data and SITC 2024 presentation

• Preclinical data presented at SITC 2024 showed DNase I significantly improved the efficacy of anti-CTLA-4 antibody therapy in colorectal cancer models.

• The combination was effective in microsatellite stable, mismatch repair proficient colorectal cancer, a group typically unresponsive to immune checkpoint inhibitors.

• DNase I may relieve NETs-mediated immunosuppression, promote tumor antigen release, and enhance immune cell access to tumor cells.

Implications for development strategy

• Proof of concept data support advancing DNase I in combination with immune checkpoint inhibitors like anti-CTLA-4 and anti-PD-1 antibodies.

• Systemic DNase I has the potential to convert non-responders to responders in cancers where NETs drive therapy resistance.

• These findings will guide clinical development plans moving forward.