{"entity":{"id":"cytomx-therapeutics","kind":"company","name":"CytomX Therapeutics","aka":[],"tldr":"CytomX Therapeutics makes 'masked' antibody medicines: a peptide covers the antibody's binding site until tumour enzymes cut it off, so the drug switches on mainly inside tumours and can hit targets that healthy tissue also carries. Its lead, an EpCAM-directed topoisomerase inhibitor conjugate for advanced bowel cancer, is in phase 1 with Fast Track status.","summary":"CytomX Therapeutics (Nasdaq: CTMX) is a clinical-stage biopharmaceutical company that pioneered conditionally activated biologics. Its Probody platform masks the antigen-binding site of an antibody with a peptide that is removed by tumour-associated proteases, so that ADCs, T-cell engagers and cytokines are activated preferentially in the tumour microenvironment, widening the therapeutic index against targets that are also expressed on healthy tissue. The lead candidate varsetatug masetecan (Varseta-M) is an EpCAM-directed, topoisomerase 1 inhibitor Probody ADC in phase 1 dose expansion for third-line or later metastatic colorectal cancer; the FDA granted Fast Track designation for relapsed or refractory metastatic colorectal cancer in August 2026. CX-801, a masked interferon alpha-2b, is in phase 1 in advanced melanoma, and CX-908 (P-cadherin x CD3) and Probody mRNA programmes are preclinical.","asOf":"2026-09-10","links":[{"label":"Official website","url":"https://cytomx.com/"},{"label":"Pipeline","url":"https://cytomx.com/pipeline/"}],"tags":[],"related":[],"cancers":["colorectal","melanoma"],"sections":["adcs","immunotherapy"],"technologies":["masked-adc","adc","t-cell-engager","cytokine-therapy"],"targets":["cd3"],"drugs":[],"companies":[],"institutions":[],"pathways":[],"terms":[],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":["Ticker, exchange and HQ confirmed via SEC EDGAR submissions data (CIK 0001501989). Investor relations pages (ir.cytomx.com) returned HTTP 403, so no funding rounds are listed; founding year not sourced."],"hq":"South San Francisco, CA","country":"US","companyType":"biotech","website":"https://cytomx.com/","ticker":"CTMX","stage":"public","investors":[],"funding":[]},"route":"/companies/cytomx-therapeutics/","neighbours":{"cancer":[{"id":"colorectal","kind":"cancer","name":"Colorectal cancer","route":"/cancers/colorectal/"},{"id":"melanoma","kind":"cancer","name":"Melanoma","route":"/cancers/melanoma/"}],"section":[{"id":"adcs","kind":"section","name":"Antibody-Drug Conjugates","route":"/fronts/adcs/"},{"id":"immunotherapy","kind":"section","name":"Immunotherapy","route":"/fronts/immunotherapy/"}],"technology":[{"id":"adc","kind":"technology","name":"Antibody-drug conjugate (ADC)","route":"/technologies/adc/"},{"id":"cytokine-therapy","kind":"technology","name":"Cytokines & engineered cytokines","route":"/technologies/cytokine-therapy/"},{"id":"masked-adc","kind":"technology","name":"Masked / conditionally active ADC","route":"/technologies/masked-adc/"},{"id":"t-cell-engager","kind":"technology","name":"T-cell engagers (bispecific)","route":"/technologies/t-cell-engager/"}],"target":[{"id":"cd3","kind":"target","name":"CD3","route":"/targets/cd3/"}]}}