VERAXA Biotech Advances Bispecific ADC Program VXA-222 Under OmniAb Collaboration

VERAXA Biotech AG (NASDAQ: VRXA) announced the advancement of its bispecific antibody-drug conjugate (bsADC) program, VXA-222, after reaching a key technical milestone in its collaboration with OmniAb (NASDAQ: OABI). The company said OmniAb has successfully completed its discovery work, allowing the program to move into its next phase. VXA-222 is designed to target two tumor antigens with a single molecule using an “AND-gate” approach intended to improve precision in treating solid tumors.

Under the collaboration launched in May 2025, OmniAb provided antibody discovery technologies, including its OmniClic platform, while VERAXA is applying its proprietary linker technology and conjugation expertise to develop and validate the lead bsADC candidate. VERAXA holds exclusive rights to develop and commercialize products arising from the collaboration, with OmniAb entitled to a share of specified revenue generated from resulting products.

The advancement of VXA-222 underscores the potential of bispecific ADCs to address limitations of traditional antibody-drug conjugates, which often suffer from on-target, off-tumor toxicity. By requiring the simultaneous presence of two tumor antigens for activation, the AND-gate design may enhance tumor selectivity and reduce damage to healthy tissues. This could be particularly significant for solid tumors, where the tumor microenvironment is heterogeneous and antigen expression can be variable.

VERAXA’s pipeline includes several proprietary formats, including its BiTAC bispecific T cell engagers and other ADC candidates. The company was founded on scientific breakthroughs at the European Molecular Biology Laboratory (EMBL) and aims to build a premier engine for next-generation antibody-based therapeutics. The collaboration with OmniAb leverages their advanced discovery platforms to identify optimal antibody pairs for bispecific targeting.

The news follows a series of developments in the bispecific ADC space, with several companies exploring dual-targeting strategies to improve therapeutic indices. Analysts view the AND-gate approach as a promising avenue to overcome dose-limiting toxicities that have hampered earlier ADCs. VERAXA’s progress with VXA-222 could validate its platform and pave the way for future clinical trials.

For more information about VERAXA Biotech and its programs, visit their newsroom. The company’s BiTAC technology is a registered trademark of VERAXA Biotech GmbH.