Multi-parameter optimization of a novel anti-TROP2 MMAE antibody-drug-conjugate for solid tumor therapy.
Fayadat-Dilman, L., Waight, A.B., Adams, L., Akbari, P., Angagaw, M., Baker, J., Castor, M., Chen, A., Chen, D., Chen, M.T., Chien, E., Chrencik, J.E., Clark, D., Dutko, J., Derebe, M., Goggins, A., Griffiths, T., Heon, M.R., Hinton, M.C., Hsieh, S., Hsu, A., Hua, Z.L., Ibrahim, M., Jia, M., Johnson, R.E., Lang, S.B., Liu, S.Y., Malashock, D., Olow, A., Oropallo, M., Partridge, A.T., Penaflor, V., Boroujeni, E.R., Ren, Z., Sathiyamoorthy, K., Uchida, M., Wiswell, D., Xia, J., Yang, P., Yearley, J., Yilmaz, S., Yu, Y., Flygare, J.A., Geierstanger, B.H., Wen, J., Seganish, W.M., Bowman, E.P.(2026) Front Oncol 16: 1915652-1915652
- PubMed: 42877637 Search on PubMedSearch on PubMed Central
- DOI: https://doi.org/10.3389/fonc.2026.1915652
- Primary Citation Related Structures: 
37RI - PubMed Abstract: 
TROP2 is expressed in many epithelial tumors including breast and lung cancers. It is a clinically validated ADC target based on approvals of sacituzumab govitecan for triple-negative breast cancer and datopotamab deruxtecan for HR-positive, HER2-negative breast cancer. An alternative cytotoxic approach was previously tested with PF-06664178/RN927C, an anti-TROP2 ADC with an auristatin payload, which entered clinical studies but could not be dosed efficaciously due to dose-limiting toxicities including skin rash, mucosal inflammation, and neutropenia. TroptimAb-SL-MMAE was engineered using an optimized anti-TROP2 sacituzumab antibody sequence (TroptimAb) to address issues related to hydrophobicity, non-specific uptake, and ADC developability. Sacituzumab was re - humanized and modified to enhance FcRn-mediated salvage which extended systemic half-life and potentially improving tumor distribution. Its affinity was avidity-tuned to preferentially bind cells with higher TROP2 expression to reduce on-target/off-tumor toxicity. An engineered cysteine in the Fc domain enabled generation of a homogeneous DAR2 ADC and shielded the linker-payload to reduce hydrophobicity and improve biophysical properties. Linker conjugation chemistry was also optimized to improve stability versus earlier cysteine-conjugated ADCs. We describe the preclinical profile of TroptimAb-SL-MMAE including its design, mechanism of action, anti-tumor activity, and pharmacokinetics.
- Discovery Biologics, Merck & Co., Inc., South San Francisco, CA, United States.
Organizational Affiliation: 



