SK Biopharmaceuticals announced on Monday that it will present research findings on its radioactive pharmaceutical (RPT) treatment SKL35501 and imaging diagnostic agent SKL35502, both targeting NTSR1, at the 2026 American Association for Cancer Research (AACR) Annual Meeting in San Diego, California, from April 17 to 22.
The AACR is a globally renowned conference where researchers and companies share cutting-edge advancements in cancer research.
This presentation provides SK Biopharmaceuticals with a platform to unveil the preclinical research results of its NTSR1-targeted RPT program, a key component of its next-generation oncology portfolio.
The significance of this presentation is underscored by SK Biopharmaceuticals’ rapid progress, advancing the pipeline to clinical trial readiness in just 18 months.
NTSR1 is known to be selectively overexpressed in various solid tumors, including colorectal and pancreatic cancers.
SK Biopharmaceuticals has developed a precision medicine approach based on a theranostics strategy, combining therapeutic and diagnostic capabilities. This innovative method uses an imaging agent to identify patients with NTSR1 expression, followed by targeted treatment with the same mechanism.
The presentation aims to showcase the global preclinical data of the NTSR1-based RPT program, highlighting both SK Biopharmaceuticals’ technological prowess and strategic development direction.
The NTSR1-targeted treatment SKL35501, utilizing the alpha-emitting isotope Actinium-225 (225Ac), demonstrated impressive tumor selectivity and retention in the human colorectal cancer cell line HCT116 model. Within 24 hours of administration, it achieved a remarkable 31% ID/g tumor accumulation, maintaining this selective targeting for up to 168 hours.
A single dose of SKL35501 showed dose-dependent tumor growth inhibition, with all dose groups experiencing significantly extended survival compared to the control. Some groups even exhibited tumor size reduction, underscoring SKL35501’s potent antitumor activity and therapeutic potential.
Importantly, the drug was swiftly cleared from non-target organs, suggesting its promise as a First-in-Class treatment.
The imaging diagnostic agent SKL35502 also yielded promising preclinical results. In the HCT116 model, it demonstrated approximately 22 times higher tumor exposure compared to blood, indicating high sensitivity. Notably, 84.12% of the total administered radioactivity was excreted within 96 hours.
Lee Dong-hoon, Chief Executive Officer (CEO) of SK Biopharmaceuticals, stated that this presentation marks a pivotal moment as it shares the next-generation RPT pipeline research on the global stage. It remains committed to accelerating RPT development and enhancing the world-class research and development (R&D) capabilities to deliver groundbreaking treatment options for patients worldwide.