Orum Therapeutics Provides Program Update and Announces Drug Candidate Nomination

BOSTON, USA & DAEJEON, South Korea, April 28, 2025 – Orum Therapeutics, Inc. (“Orum” or the “Company”) (KRX: 475830), a public biotechnology company pioneering the field of degrader-antibody conjugates (DACs), today announced a strategic update to its pipeline. Orum has discontinued further clinical development of ORM-5029, a HER2-targeted GSPT1 degrader-antibody conjugate (DAC). This decision follows an internal assessment of the program’s clinical progress and incorporates information previously disclosed. Concurrently, Orum announced the nomination of a new drug candidate, ORM-1153, in development for the treatment of hematologic malignancies.

ORM-1153 is a novel DAC engineered using Orum’s proprietary Dual-Precision Targeted Protein Degradation (TPD²®) approach, which combines the catalytic protein degradation mechanism of TPDs with the tumor-targeting capabilities of therapeutic antibodies. The candidate targets GSPT1, a translation termination factor highly relevant in hematologic malignancies, and an undisclosed tumor-associated antigen to enhance selectivity and broaden the therapeutic window.

In preclinical studies, ORM-1153 demonstrated potent anti-tumor activity and a favorable safety profile, including in non-human primate models. ORM-1153 demonstrated picomolar potency in target-expressing cell lines and showed greater potency than existing small molecule GSPT1 degraders. In vivo, a single dose of ORM-1153 led to strong anti-tumor activity in relevant xenograft models. Orum plans to advance the program into IND-enabling studies and anticipates presenting additional data at a scientific conference later this year.

“After careful review of available clinical and preclinical data, we have concluded clinical development of ORM-5029,” said Sung Joo (SJ) Lee, Ph.D., Founder and CEO of Orum Therapeutics. “This decision reflects our continued commitment to patient safety and our strategic focus on advancing the next generation of degrader-antibody conjugates with a clearly defined risk-benefit profile. We look forward to advancing next-generation programs emerging from our proprietary platform, like ORM-1153.”

Dr. Lee continued, “ORM-1153 leverages learnings from all our programs and clinical experience to build potent, selective, and tumor-targeted protein degrader therapeutics that address serious unmet needs in oncology. We remain confident in the promise of our Dual-Precision Targeted Protein Degradation GSPT1 platform and are excited to progress this new candidate toward the clinic.”

About Orum’s TPD²® Approach

Orum’s unique Dual-Precision Targeted Protein Degradation (TPD²®) approach builds novel targeted protein degraders combined with the precise cell delivery mechanisms of antibodies to generate innovative, first-in-class, cell-selective TPDs for the treatment of cancer. Orum has developed new targeted protein degrader payloads to specifically degrade an intracellular target protein within cancer cells via the E3 ubiquitin ligase pathway. Conjugated to antibodies, the payloads are designed to be delivered specifically to target cells and precisely degrade the intracellular target protein of interest.

About Orum Therapeutics

Orum Therapeutics is a public biotech company pioneering the development of cell-specific, targeted protein degraders (TPD²®) with the precision of antibody targeting to improve cancer treatment for more patients. The company is advancing its GSPT1-directed TPD² programs and developing novel degrader payloads to expand the potential of targeted protein degradation. Orum's novel targeted protein degrader payloads are designed to selectively degrade key intracellular proteins, offering a highly targeted approach to treating difficult-to-treat diseases. 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 potential selectivity, therapeutic window, therapeutic benefits, and indications for ORM-1153; the potential for preclinical study results to indicate positive results in IND-enabling studies and any clinic trial; the potential for commencement of IND-enabling studies, the filing and approval of any IND application, and initiation of clinical trials; the presentation of additional ORM-1153 data during 2025; the promise of Orum’s GSPT1 platform; and the development of new payload platforms and programs and the expansion 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; the uncertainty in approval of any IND that might be filed; 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 presentation 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.

Contacts

Corporate: Kayla (Gyebang) Mo, Director, IR/PR, Orum Therapeutics, Inc., media@orumrx.com

Media: Jessica Yingling, Ph.D., President, Little Dog Communications Inc., jessica@litldog.com