Scorpion Therapeutics to Present STX-478 Phase 1/2 Data at ESMO 2024

Scorpion Therapeutics, Inc., a leading clinical-stage oncology company focused on precision oncology, has announced the presentation of initial clinical results from their Phase 1/2 study of STX-478, a mutant-selective PI3Kα inhibitor. This presentation will take place in a Proffered Paper late-breaking session at the European Society for Medical Oncology (ESMO) Congress 2024, scheduled for September 13-17 in Barcelona, Spain.

Mark Chao, M.D., Ph.D., Chief Medical Officer of Scorpion, emphasized the significance of this milestone for individuals suffering from advanced solid tumors driven by PI3Kα mutations, such as HR+/HER2- breast cancer. He noted that while PI3Kα has long been an important target in cancer treatment, existing treatment options are limited by toxicity and insufficient efficacy due to a lack of mutant selectivity. The clinical data from STX-478 aims to provide early insights into its potentially superior outcomes in PI3Kα-mutated cancers. The presentation will include initial assessments of safety, pharmacokinetic and pharmacodynamic data, as well as preliminary efficacy data.

Details for the Proffered Paper presentation are as follows:
- Title: First-in-human Results of STX-478, a Mutant-selective PI3Kα Inhibitor, in Advanced Solid Tumor Patients
- Presentation Number: LBA27
- Session Name: Proffered paper session 2: Developmental therapeutics (ID 156)
- Session Date & Time: Sunday, September 15, 2024, 14:45 – 16:15 CEST (8:45 a.m. – 10:15 a.m. ET)
- Presentation Time: 14:55 – 15:05 CEST (8:55 a.m. – 9:05 a.m. ET)
- Location: Salamanca Auditorium - Hall 5
- Presenter: Alberto J. Montero, M.D. (University Hospitals Cleveland, OH, USA)

According to ESMO, the late-breaking abstract will be published on their website at 00:05 CEST on September 15 (6:05 p.m. ET on September 14). Following the ESMO 2024 Congress, the data presented will be accessible in the "Publications & Presentations" section on Scorpion's website.

STX-478 was developed to enhance outcomes for patients with PI3Kα mutations, which are prevalent drivers of cancer, affecting over 166,000 patients annually in the United States alone with various solid tumors including breast and gynecological cancers. In preclinical studies, STX-478 demonstrated strong activity across multiple PI3Kα mutations while avoiding inhibition of wild-type PI3Kα in normal tissues, which has been a limitation of prior non-selective PI3Kα inhibitors due to on-target toxicities. Scorpion's Phase 1/2 clinical trial, which is global, multi-center, and open-label, aims to evaluate the safety and tolerability of STX-478 in escalating doses for patients with locally advanced or metastatic HR+/HER2- breast cancer and other solid tumors with PI3Kα mutations. Launched in 2023, this program has quickly advanced and now includes multiple expansion cohorts across various solid tumors and in breast cancer both as a monotherapy and in combination therapies with fulvestrant and CDK4/6 inhibitors.

Scorpion Therapeutics is dedicated to transforming cancer treatment through a proprietary platform that integrates advanced technologies in cancer biology, medicinal chemistry, and data sciences. Their goal is to develop highly selective small molecule compounds targeting an extensive range of cancer drivers. The company aims to advance a broad pipeline of optimized compounds, including best-in-class molecules for validated oncogene targets, and first-in-class molecules for both previously undruggable and novel cancer targets.