FDA Clears Orum Therapeutics to Begin Testing Novel Leukemia Drug ORM-1153
Orum Therapeutics announced that the U.S. Food and Drug Administration has cleared the company's Investigational New Drug application for ORM-1153, an experimental therapy for patients with relapsed or refractory acute myeloid leukemia and other blood cancers. The biotechnology company plans to initiate a first-in-human Phase 1 clinical study by the end of 2026.
ORM-1153 represents a novel class of cancer treatment called degrader-antibody conjugates. The drug combines targeted antibody delivery with protein degradation technology, specifically designed to eliminate GSPT1—a translation termination factor that plays a critical role in cancer cell growth—within CD123-expressing cancer cells. CD123, also known as IL-3Rα, is overexpressed in approximately 70-90% of acute myeloid leukemia cases, making it a validated therapeutic target for this disease.
GSPT1 has emerged as an important target for protein degradation therapy in cancer, with studies demonstrating that eliminating this protein can inhibit cancer cell growth across multiple cancer types including AML. The drug works by hijacking the E3 ubiquitin ligase pathway, the cellular machinery responsible for marking proteins for degradation, a mechanism that has become central to developing new targeted protein degradation therapies.
Addressing a Critical Medical Need
The patient population targeted by ORM-1153 faces particularly dire circumstances. Relapsed or refractory acute myeloid leukemia carries a poor prognosis, with 5-year survival rates of approximately 10% for relapsed patients and even lower for those with refractory disease. This represents a significant unmet medical need in oncology.
According to preclinical data presented at the American Association for Cancer Research Annual Meeting 2026—one of the world's largest cancer research conferences with over 20,000 attendees annually—ORM-1153 demonstrated broad activity across AML models. The drug showed efficacy in primary patient samples and in models relevant to TP53 mutations, which occur in approximately 10-20% of AML cases at diagnosis and are associated with particularly poor outcomes and resistance to standard therapies.
The preclinical studies also revealed low-dose in vivo activity and favorable repeat-dose tolerability, key indicators for potential clinical success.
Clinical Trial Plans
The upcoming Phase 1 study will evaluate the safety, tolerability, pharmacokinetics, pharmacodynamics, and preliminary antitumor activity of ORM-1153. The multicenter trial is expected to enroll approximately 42 patients initially at U.S. clinical sites, with potential expansion to other regions.
Dr. Olaf Christensen, Chief Medical Officer of Orum Therapeutics, stated that the IND clearance represents an important milestone for the company. By combining cell-selective delivery with targeted protein degradation in a single molecule, we believe ORM-1153 has the potential to improve treatment efficacy and tolerability for patients with severe hematologic malignancies.
Platform Technology and Market Context
Orum's Dual-Precision Targeted Protein Degradation platform builds on the proven success of antibody-drug conjugates, a therapeutic approach that has generated multiple FDA-approved products and billions in revenue in oncology. The company's degrader-antibody conjugate technology aims to extend this validated delivery approach to targeted protein degradation.
Orum Therapeutics, which completed its initial public offering on the Korea Exchange in December 2023 raising approximately 52 billion won (about $40 million), is headquartered in Daejeon, South Korea, with operations in Lexington, Massachusetts. The company trades on the KOSDAQ under ticker symbol 475830.
The company will host a conference call on Monday, August 24, at 7:00 a.m. Korea Standard Time (Sunday, August 23, at 6:00 p.m. Eastern Daylight Time) to discuss the IND clearance and provide additional details about the Phase 1 clinical study.
