SOTIO doses first patient in CDH17-targeting ADC trial for CRC
SOTIO Biotech has dosed the first patient in its CADENCIA-01 Phase 1/2 clinical trial, marking the clinical debut of SOT109, an antibody-drug conjugate targeting CDH17, a cell-surface antigen expressed in more than 90% of colorectal cancer cases. The Prague- and Basel-headquartered company, which is owned by Czech investment group PPF, said initial safety and early efficacy signals are expected within the next 12 to 18 months.
SOT109 pairs a fully human, high-internalising antibody with Lonza's SYNtecan E linker-payload technology at a drug-to-antibody ratio of four. The company says the payload's high cell permeability is expected to produce a pronounced bystander effect, reducing the risk of resistance mechanisms that have limited earlier-generation ADCs. Preclinical studies in non-human primates showed what SOTIO described as a favourable pharmacokinetic and safety profile, and in vivo colorectal tumour models showed sustained regressions across multiple challenging settings.
Trial design and regulatory status
The CADENCIA-01 study (NCT07693751) is a dose-escalation and dose-optimisation trial enrolling patients with advanced unresectable or metastatic colorectal cancer who have exhausted standard approved therapies. Sites are opening across Europe and the United States, and the FDA cleared an Investigational New Drug application ahead of the US cohort. SOT109 received FDA Fast Track Designation in July 2026, a status SOTIO says is unique among CDH17-directed ADCs currently in development.
Vivi Boura, chief medical officer at SOTIO, noted that patients with advanced colorectal cancer face limited options after progression on standard regimens. "This study is designed to efficiently evaluate safety and early signs of anti-tumour activity in a well-defined population, with the goal of establishing a rapid path toward clinical proof of concept and supporting potential expansion into broader gastrointestinal indications," she said.
Market context and competitive landscape
CDH17 has attracted growing attention as a GI tumour antigen because of its near-universal expression in colorectal cancers and its largely restricted distribution in normal tissue, a profile that theoretically supports a favourable therapeutic window. SOTIO's claim to be the only company with a CDH17-targeting ADC bearing FDA Fast Track Designation appears consistent with publicly available information, though several academic and early-stage commercial programmes have been reported in preclinical stages.
The broader ADC field has been one of the most active areas in oncology drug development over the past several years, with a succession of high-value licensing and acquisition deals underscoring investor appetite for differentiated conjugate technologies. Colorectal cancer, the second-leading cause of cancer death globally, remains underserved by targeted biologics relative to lung or breast cancer, and regulators on both sides of the Atlantic have signalled willingness to support accelerated development paths for genuine innovations in the space.
SOTIO's pipeline extends beyond SOT109. Its LRRC15-targeting ADC, SOT106, holds both Orphan Drug and Fast Track designations for sarcoma and other solid tumours, and is described as the company's other next-generation programme entering the clinic in 2026. A PD-1-targeting immunocytokine, SOT201, is already in a Phase 1 study. The company has positioned itself as building a solid-tumour ADC franchise, and CADENCIA-01 is the first clinical proof-of-concept opportunity to test that ambition. Investors and potential partners will be watching the interim safety read-out, expected in late 2027 at the earliest, for signals that the CDH17 hypothesis translates from preclinical models to patients.