Main Conference Day 3Wednesday, 16 December 2026 - PT (Pacific Time, GMT-08:00)

OncoNano Medicine is developing ONM-421, an ON-BOARD™ ultra-pH-sensitive polymer-drug conjugate delivering MMAE, designed to enhance tumor-selective drug delivery. ONM-421 demonstrated broader antigen independent antitumor efficacy compared with an MMAE-based antibody-drug conjugate, which showed limited efficacy in an antigen-low model. ONM-421 also demonstrated improved tolerability versus chemotherapy at an efficacious dose. The data highlight enhanced payload stability and protection during circulation, reinforcing the platform’s ability to enable targeted tumor delivery while reducing off-target toxicity.

This presentation will highlight the development of DLL3-targeted antibody-based radiotheranostic agents, spanning immunoPET imaging and targeted radioligand therapy. Preclinical and early clinical studies demonstrate the potential of DLL3 as a platform for patient selection, treatment monitoring, and precision radionuclide therapy across neuroendocrine malignancies.

Clinical successes of small molecule and peptide radiopharmaceuticals for prostate and neuroendocrine tumors suggest also revisiting antibodies for targeted delivery of radionuclides. Advantages of engineered antibodies and fragments include the ease of pairing diagnostic (for SPECT or PET) and therapeutic (alpha- or beta-emitting radionuclides) in a “theranostic” approach. Examples will include diabodies and minibodies for immunoPET detection of immune responses and a PSCA-specific engineered antibody for radioimmunotherapy.

Single-cell transcriptomic profiling identified uPAR as a disease-associated myeloid target in rheumatoid arthritis. Anti-uPAR ADCs were designed to selectively deliver BCL-2 family inhibitors to inflammatory myeloid cells, enabling targeted depletion of activated human monocytes and macrophages in vitro. To overcome species-specific differences in target expression and payload sensitivity, an MMAF ADC was used for in vivo proof-of-concept. This work highlights both the promise and translational challenges of ADCs for autoimmune disease.

ADCs have transformed the therapeutic landscape of oncology and have the potential to shift the treatment paradigm for immune and inflammatory (I&I) diseases by enabling the targeted delivery of payloads to disease-driving immune or inflammatory cells. Hummingbird Bioscience's platform & technologies engineers next-generation ADCs that have the promise to address key limitations of current I&I therapies for patients, including: efficacy ceiling, durability, and tolerability.