9MW2921 is a next generation antibody-drug conjugate (ADC) developed by Mabwell based on IDDC™ (Interchain-Disulfide Drug Conjugate) plateform for the treatment of solid tumors. It is an innovative antibody molecule linked to a novel payload (TOP1i) by a novel linker with fully autonomous intellectual property right. When 9MW2921 enters the body, it can specifically bind to antigens on the cell membrane surface, be internalized and transferred to the lysosome, release cytotoxic drug, and induce the apoptosis of tumor cells.

9MW2921 is pharmaceutical characterized as stable structure, homogeneous composition, high purity, and it is suitable for industrial scale-up. Compared with ADCs of the same class under development at home and abroad, 9MW2921 is significantly improved and optimized in endocytic activity, plasma stability, drug release characteristics, bystander killing effect, etc. In vivo pharmacodynamic studies demonstrated that 9MW2921 had a better tumor killing activity. In animal safety evaluation models including cynomolgus monkeys and rats, the on-target and off-target toxicities of 9MW2921 were effectively controlled, indicating that 9MW2921 has good safety profile and pharmacokinetic properties.

Belonging to the TACSTD family, Trop-2 is a cell surface glycoprotein encoded by the TACSTD gene. It is expressed in normal tissues at low levels, while overexpressed in multiple malignant tumors. Trop-2 expression correlates with tumor aggressiveness. Trop-2 overexpression promotes the growth, proliferation, and metastasis of tumor cells.

Next generation antibody-drug conjugate plateform IDDC™

Mabwell has developed multiple ADC technology plateforms, and its anti-Nectin-4 ADC (R&D code: 9MW2821) is currently in the phase II clinical study.

IDDC™ is a next generation ADC site-specific conjugate technology plateform independently developed by Mabwell. It is composed of multiple systematized core patent technologies including site-specific conjugate process DARfinity™, special designed linker IDconnect™, novel payload Mtoxin™, and conditional release structure LysOnly™.

The next generation ADCs developed based on the above systematic patent technologies will carry better structural homogeneity, quality stability, pharmacodynamics and tolerability. Currently, the IDDC™ plateform has been validated in several products under development. It is expected multiple ADC products will enter clinical development in 2023 and 2024.