On April 29, 2025 SOTIO Biotech, a clinical-stage biopharmaceutical company owned by PPF Group, this week reported preclinical data on two of its leading antibody-drug conjugate (ADC) candidates, SOT109 and SOT106, at the American Association for Cancer Research (AACR) (Free AACR Whitepaper) Annual Meeting in Chicago, IL (Press release, SOTIO, APR 29, 2025, View Source [SID1234652336]).

Schedule your 30 min Free 1stOncology Demo!
Discover why more than 1,500 members use 1stOncology™ to excel in:

Early/Late Stage Pipeline Development - Target Scouting - Clinical Biomarkers - Indication Selection & Expansion - BD&L Contacts - Conference Reports - Combinatorial Drug Settings - Companion Diagnostics - Drug Repositioning - First-in-class Analysis - Competitive Analysis - Deals & Licensing

                  Schedule Your 30 min Free Demo!

Preclinical data on SOT109 (anti-CDH17 ADC) and SOT106 (anti-LRRC15 ADC) demonstrate strong anti-tumor activity and favorable tolerability profiles across multiple tumor models, supporting their potential as groundbreaking ADC therapies for various solid tumor types.

SOT109 is tailored to be a best-in-class ADC exploiting the highly promising target of CDH17 for treatment of gastrointestinal cancers including colorectal cancer (CRC), where unmet need remains very high. ADCs have shown limited clinical success in CRC to date largely due to a lack of ideal target antigens. CDH17 is a highly promising target antigen homogenously overexpressed in more than 90% of CRC and abundantly expressed in other GI cancers. Its expression in normal adult tissues is largely restricted to the GI tract, reducing the risk of off-target toxicity. SOT109 utilizes a proprietary, highly internalizing and fully human antibody combined with Synaffix B.V.’s leading ADC technology platform. Both the antibody and the epitope it is targeting, as well as the linker/payload design, have been selected to maximize its efficacy and safety.

SOTIO’s poster presentation on SOT109 showed the following:

SOT109 exhibited potent efficacy, producing significant and sustained tumor regressions in several in vivo colorectal tumor models, including cell-derived and patient-derived xenografts.
The doses tested in these studies were well tolerated in mice, with no dose-limiting toxicities observed. Subsequent studies in non-human primates confirmed a favorable pharmacokinetic and safety profile.
SOT106, leveraging LigaChem Biosciences’ clinically validated ConjuAll ADC platform for tumor-specific MMAE release, is a potentially best-in-class ADC for the clinically-validated target LRRC15. SOTIO’s oral presentation on SOT106 showed the following:

SOT106 demonstrated exceptional efficacy in an LRRC15 low-expressing patient-derived xenograft model of pediatric osteosarcoma, achieving significant tumor regression where a first-generation LRRC15-targeting ADC benchmark therapy was ineffective. This further supports its therapeutic potential across a broad range of target expression levels.
Complete responses and potent antitumor efficacy were also observed across a range of other models where LRRC15 is expressed directly on tumor cells, including multiple subtypes of soft tissue sarcoma, a therapy-resistant non-small-cell lung cancer model, and head and neck squamous cell carcinoma.
SOT106 displays a favorable pharmacokinetic and safety profile, good stability in vivo, and a high therapeutic index.
"The data we presented at AACR (Free AACR Whitepaper) this week highlights the strength of our next-generation ADCs by addressing areas of high unmet need in oncology," said Martin Steegmaier, Ph.D., chief scientific officer at SOTIO. "SOT109 continues to show excellent tolerability and strong anti-tumor activity across multiple preclinical models of colorectal cancer, while SOT106 offers a novel precision approach with broad applicability in LRRC15+ sarcomas and other solid tumors. These findings mark important progress in our pipeline and reinforce our commitment to developing highly differentiated ADCs for difficult to treat solid tumors."

Presentation materials will be available here after the presentation concludes.