Bristol Myers Squibb has dropped its only clinical-stage CD33-targeted degrader-antibody conjugate for acute myeloid leukemia. The company ended development of BMS-986497, which it acquired from Orum Therapeutics less than three years ago, after reviewing Phase I trial results.
Orum was notified of the decision on September 16, 2026. This move immediately canceled up to USD 80 million in remaining milestone payments. Orum keeps the USD 100 million upfront payment it received when the deal closed in October 2023. The original agreement, worth USD 180 million, did not include royalties, so Orum will not receive further payments regardless of what happens next.
The Phase I clinical trial for BMS-986497 included both monotherapy and combination regimens with azacitidine and venetoclax for relapsed or refractory AML and MDS across the US, Europe, and Canada.
BMS-986497, previously called ORM-6151, was based on Orum’s TPD² platform. It combined an anti-CD33 antibody with a GSPT1 protein degrader payload and was tested in patients with acute myeloid leukemia and high-risk myelodysplastic syndromes. The trial included both monotherapy and combinations with azacitidine and venetoclax in the US, Europe, and Canada. Bristol Myers Squibb has not explained why it ended the program, and there is no sign that rights to the drug will return to Orum.
With this termination, gemtuzumab ozogamicin is now the only approved CD33-directed agent for AML. Bristol Myers Squibb’s exit leaves no clinical-stage CD33-targeted DACs in development, a sharp drop for a field that once showed promise.
Orum Therapeutics is now focusing on its internal pipeline and DAC platform. Its next AML candidate, ORM-1153, targets CD123 and also uses the GSPT1 degrader payload. ORM-1153 received FDA investigational new drug clearance in August 2026 and is set to begin first-in-human trials. Preclinical data were presented at the American Association for Cancer Research meeting in April 2026.
According to Korean regulatory disclosures, after BMS's decision to discontinue BMS-986497, the rights to the asset do not revert to Orum Therapeutics. The company is now focusing on advancing its internal pipeline, including ORM-1153, which received FDA IND clearance in August 2026.
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Despite BMS’s withdrawal, the broader DAC field remains active. Johnson & Johnson bought Firefly Bio’s preclinical DAC platform for USD 1 billion in June 2026. Roche partnered with C4 Therapeutics in April 2026 for two oncology DAC programs, paying USD 20 million upfront and offering more than USD 1 billion in potential milestones. Orum also made a separate deal with Vertex Pharmaceuticals in July 2024, giving access to its TPD² platform for up to three DAC programs as gene-editing conditioning agents, for USD 15 million upfront and up to USD 945 million in potential value.
Bristol Myers Squibb’s sudden exit from the BMS-986497 program highlights how even large deals and new drug approaches can be cut short by early clinical results. The lack of royalties and the loss of USD 80 million in milestones show the risks involved in biotech licensing. Orum is now turning to CD123 and continuing to make platform deals, but the clinical-stage CD33 DAC pipeline is now empty—a setback for a modality once expected to change AML treatment.
As reported by Fierce Biotech, the BMS-986497 program was terminated after a Phase I data review, and milestone payments ended the same day Orum was notified.
Financial details of the original BMS–Orum deal, including the upfront and milestone structure, were confirmed in an English-language Maeil Business report covering the October 2023 transaction.
