SOTIO's SOT106 ADC Shows Promise in Sarcoma Treatment with Strong Preclinical Results
Key Insights
SOTIO Biotech (search) presented positive preclinical data for SOT106, an anti-LRRC15 (search) antibody-drug conjugate targeting sarcomas, at the CTOS Annual Meeting.
The ADC demonstrated potent nanomolar cytotoxicity in vitro with bystander effects and achieved complete tumor responses at 1 mg/kg in patient-derived xenograft models.
Non-human primate studies revealed a favorable pharmacokinetic profile and high therapeutic index, with dose-limiting toxicities consistent with known MMAE (search) effects.
SOTIO Biotech (search) announced favorable preclinical results for SOT106, its antibody-drug conjugate targeting LRRC15 (search)-positive sarcomas, at the Connective Tissue Oncology Society (CTOS) Annual Meeting in Boca Raton, Florida. The clinical-stage biopharmaceutical company, owned by PPF Group (search), presented data positioning SOT106 as a potential best-in-class treatment for sarcomas and other LRRC15-positive malignancies.
Robust Preclinical Efficacy Profile
The preclinical studies demonstrated SOT106's potent antigen-specific cytotoxicity in vitro, achieving nanomolar activity with a pronounced bystander effect. In vivo studies showed dose-dependent tumor regression, including complete responses at 1 mg/kg dosing. The ADC surpassed benchmarks in both soft tissue sarcoma (search) and osteosarcoma (search) patient-derived xenograft (PDX) models, demonstrating efficacy even in tumors with low-to-medium LRRC15 (search) expression and in orthotopic osteosarcoma models.
Favorable Safety and Pharmacokinetic Profile
An exploratory non-human primate study revealed SOT106's favorable pharmacokinetic profile and high therapeutic index. The dose-limiting toxicities observed aligned with known effects of MMAE (search) (monomethyl auristatin E), the cytotoxic payload commonly used in ADCs, suggesting a predictable safety profile.
"Sarcomas continue to represent a significant unmet medical need, with limited therapeutic progress over the past several decades," said Amy Jensen-Smith, chief scientific officer of SOTIO. "LRRC15 (search) is a clinically validated target broadly expressed across sarcoma (search) subtypes, making it an ideal candidate for a differentiated ADC approach."
Clinical Development Timeline
SOTIO is advancing SOT106 through IND-enabling studies toward an anticipated IND filing in Q4 2026. The company has developed and validated a proprietary, highly sensitive, and specific LRRC15 (search) immunohistochemistry assay to guide patient selection in upcoming clinical trials.
Jensen-Smith emphasized that the non-human primate data "reinforce our confidence in SOT106's therapeutic potential and mark a critical step toward delivering a novel treatment option for patients facing these aggressive diseases."
Broader Pipeline Context
SOT106 represents part of SOTIO's innovative pipeline of mono- and bispecific solid tumor ADC programs at various stages of preclinical development. The company is also developing SOT109 for colorectal cancer (search) treatment and SOT201, a next-generation PD-1 (search)-targeting immunocytokine currently being evaluated in the Phase 1 VICTORIA-01 study for patients with solid tumors (search).
The company is exploring partnering opportunities as the program advances toward clinical readiness, positioning SOT106 as a potential breakthrough therapy for sarcoma (search) patients who have faced limited treatment advances in recent decades.