STORM Therapeutics doses first patient with oral METTL3 targeting drug candidate in a solid tumor Phase 1 study

STC-15 is the first molecule specifically targeting an RNA methyltransferase to enter clinical development

CAMBRIDGE, England, Nov. 23, 2022 /PRNewswire/ -- STORM Therapeutics Ltd. (STORM), the biotechnology company discovering and developing novel small molecule therapies targeting RNA modifying enzymes (RMEs) for oncology and other diseases, today announces that the first patient has been dosed with STC-15, the Company's first-in-class clinical candidate.

An orally bioavailable, highly selective METTL3 inhibitor, STC-15 is the first molecule specifically targeting an RNA methyltransferase enzyme to enter clinical development. This Phase 1 study is a multiple ascending dose escalation trial aiming to enroll 40-60 patients to measure safety, pharmacokinetics, target engagement, biomarkers related to mechanism, and anti-tumor efficacy in patients with solid tumors. Details of the study can be found on clinicaltrials.gov under the identifier NCT05584111.

Preclinical activity was demonstrated with STC-15 through direct cytotoxic and anti-cancer immune response mechanisms in solid tumor and leukemia models. Data indicated enhanced interferon signaling and synergy with T cell checkpoint blockade as an important mechanism of action of STC-15 resulting in tumor regression and anti-cancer immunity in rodent models.

Dr Jerry McMahon, CEO of STORM Therapeutics, said: "This is a major milestone for STORM as we enter clinical development with our lead candidate STC-15 and continue progressing a pipeline targeting RNA modifying enzymes beyond METTL3. We intend to exhibit preclinical data related to STC-15 at future medical conferences this year as we execute our Phase 1 study in patients with solid tumors. We anticipate presenting results from our Phase 1 study in 2023."

Josefin-Beate Holz, MD, CMO of STORM Therapeutics, added: "I am delighted with the successful initiation of STORM's first candidate into the clinic from our innovative and proprietary pipeline. Clinical development allows us to establish meaningful clinical benefit with RNA modifying enzyme inhibitors in cancer patients. This first trial is a groundbreaking milestone for the drug class and we are looking forward to receiving the emerging data from the study."

Justin Moser, MD, Associate Clinical Investigator of HonorHealth Research Institute, the first clinical site to recruit patients to the STC-15 study, commented: "Our goal at HonorHealth Research Institute is to offer tomorrow's potential cures to our patients, today. We are excited about our collaboration with STORM which allows us to offer STC-15 and other cutting-edge, first-in-class trial options to our patients."

About STORM Therapeutics

STORM Therapeutics (STORM) is a biotechnology company creating novel therapies that inhibit RNA modifying enzymes (RME) for use in oncology and other diseases. There are more than 150 RNA modifications reported and approximately 300 RNA modifying enzymes which represent novel therapeutic targets.

STORM has leveraged its first-mover advantage to establish a novel drug discovery and RNA analytics platform leading to the identification of novel targets and a proprietary pipeline of first-in-class small-molecule drug candidates for potential use in oncology, inflammation, viral infections and CNS diseases.

The pipeline is exemplified by STORM's METTL3 inhibitor (STC-15) which received FDA approval to support initiation of its Phase 1 clinical trial in cancer patients in 2022. STC-15 represents the first RNA modifying enzyme inhibitor to enter clinical evaluation in humans. Additional candidates are planned for advancement into IND-track activities in 2023.

STORM investors include M Ventures (the corporate venture capital arm of Merck KGaA, Darmstadt, Germany), Pfizer Ventures, Taiho Ventures LLC, Cambridge Innovation Capital I Limited, Seroba Life Sciences, IP Group plc, Fast Track Initiative (FTI), and the University of Tokyo Innovation Platform.

For more information, please visit www.stormtherapeutics.com

About STC-15

STORM's lead program STC-15 is a first-in-class clinical candidate and is the first inhibitor of RNA modification to enter clinical development in humans. STC-15 is an oral small molecule that inhibits METTL3 which is an RNA methyltransferase implicated in oncology and other diseases. Certain RNA methyltransferases are important regulators of RNA sensing and innate immune activation and represent novel immune-regulatory targets.

STC-15 has also been shown to inhibit tumor growth through mechanisms involving anti-cancer immune responses such as changes in interferon signaling and synergy with T cell checkpoint blockade. In addition, STC-15 has shown efficacy in leukemia models via mechanisms including inhibition of leukemia stem cell function.

STC-15 commenced its Phase 1 clinical study in cancer patients with solid tumors in November 2022 when the first patient was dosed.