Orum Therapeutics Doses First Patient in Phase 1 Trial of ORM-1153, a CD123-GSPT1 Degrader-Antibody Conjugate
BOSTON and DAEJEON, South Korea, Oct. 13, 2026 (GLOBE NEWSWIRE) — Orum Therapeutics (“Orum” or the “Company”) (KRX: 475830), a biotechnology company pioneering the field of degrader-antibody conjugates (DACs), today announced that the first patient has been dosed in a Phase 1 clinical trial evaluating ORM-1153, the Company’s investigational CD123-GSPT1 DAC, in patients with relapsed or refractory acute myeloid leukemia (AML) and other CD123-expressing hematologic malignancies.
ORM-1153 combines Orum’s internally developed CD123-targeting antibody with a proprietary GSPT1 degrader payload. The antibody was engineered for efficient internalization into target cells and reduced Fc-gamma receptor interactions, with a linker designed for plasma stability. Preclinical studies demonstrated activity across primary AML patient samples and models with TP53 mutations, providing a rationale for evaluating ORM-1153 in patients with difficult-to-treat disease.
“We have built a substantial preclinical data package for ORM-1153, and our task now is to establish how those findings translate clinically,” said Olaf Christensen, M.D., Chief Medical Officer of Orum Therapeutics. “The preparation of our team and the support of our clinical site partners enabled us to move efficiently from IND clearance through site activation to dosing. The study will allow us to assess whether the improvements in payload delivery observed preclinically translate into a favorable balance of activity and tolerability in patients.”
“Patients with relapsed or refractory AML, particularly those with high-risk molecular features, continue to have poor outcomes and need additional treatment options,” said Andrew Sochacki, M.D., Associate Director of Hematology at START Midwest. “Targeted delivery of a GSPT1 degrader offers a different approach to treating these cancers. This Phase 1 study will provide important initial information about ORM-1153’s safety, pharmacology, and potential activity in patients.”
The first-in-human Phase 1 study is an open-label, dose-escalation trial designed to identify the optimal biological dose and evaluate the safety and tolerability of ORM-1153. The study will also characterize its pharmacokinetic and pharmacodynamic profile and assess preliminary antileukemic activity. Approximately 42 patients are expected to be enrolled at multiple clinical sites initially in the United States, potentially followed by sites in other regions. Additional information is available on ClinicalTrials.gov under identifier NCT07809906.
About ORM-1153
ORM-1153 is a CD123-GSPT1 degrader-antibody conjugate developed using Orum’s proprietary GSPT1 degrader platform. The molecule combines a proprietary GSPT1-degrading payload with an internally developed anti-CD123 antibody engineered for high internalization efficiency through a cleavable β-glucuronide linker. Following internalization and payload release, ORM-1153 is designed to induce cancer cell death through targeted degradation of GSPT1. In preclinical studies presented at the American Association for Cancer Research (AACR) Annual Meeting 2026, ORM-1153 demonstrated activity across primary AML patient samples and TP53-relevant models, along with antileukemic activity at low doses in vivo. Its safety and efficacy in patients have not been established.
About Orum Therapeutics
Orum Therapeutics is a public biotechnology company developing degrader-antibody conjugates (DACs) to deliver protein degraders to specific cells and eliminate proteins that drive disease. Its lead program, ORM-1153, targets CD123 to deliver a GSPT1 degrader to cancer cells in acute myeloid leukemia and other hematologic malignancies. Orum is also developing new DAC payload platforms beyond GSPT1 to broaden the targets and diseases it can pursue across oncology and other therapeutic areas. Orum is located in Daejeon, South Korea, and Lexington, MA, US. For more info, visit www.orumrx.com.
Orum Therapeutics Forward-Looking Statements
This press release contains forward-looking statements that are based on the current expectations and beliefs of Orum Therapeutics, Inc. (“Orum”). Statements in this release regarding matters that are not historical facts, including, but not limited to, statements relating to the design, initiation, conduct, enrollment, timing, escalation, completion, and potential results of the Phase 1 clinical trial of ORM-1153; the projected number of patients and the location of clinical trial sites; the safety, tolerability, pharmacokinetics, pharmacodynamics, preliminary antileukemic activity, and potential therapeutic value of ORM-1153; the successful translation of preclinical findings into clinical results; the potential treatment of patients with AML, including patients with TP53 mutations, and other CD123-expressing hematologic malignancies; the potential success of Orum’s DAC approach and development of additional degrader payload platforms; and the advancement of Orum’s pipeline, are forward-looking statements.
These forward-looking statements are based on management’s expectations and assumptions as of the date of this release and are subject to numerous risks and uncertainties, which could cause actual results to differ materially from those expressed or implied by such statements. These risks and uncertainties include, without limitation, the uncertainty of success in research and development activities; risks related to clinical trials, including potential delays in enrollment or trial conduct, safety issues, or negative results; competition from alternative therapies; and risks related to the recruitment and retention of key employees, fluctuating markets and economic conditions, and future fundraising. The forward-looking statements in this release speak only as of the date of this release, and Orum undertakes no obligation to update or revise any of the statements. Orum cautions investors not to place considerable reliance on the forward-looking statements contained in this release.
CONTACT: Contacts Corporate: IR/PR, Orum Therapeutics, media@orumrx.com Media: Jessica Yingling, Ph.D., President, Little Dog Communications Inc., jessica@litldog.com
