Abstract B017: A sphingolipid-derived paclitaxel nanovesicle enhances efficacy of combination therapies in triple-negative breast cancer and pancreatic cancer

Abstract Taxol and Abraxane, the US Food and Drug Administration-approved paclitaxel (PTX) formulations, have revealed hypersensitivity due to excipients and mediocre efficacy due to insufficient tumor penetration, respectively. Here we developed a sphingolipid-derived PTX nanovesicle (paclitaxome) via covalently conjugating PTX to sphingomyelin, which improved pharmacokinetics and enhanced efficacy in metastatic triple-negative breast cancer and pancreatic cancer female mice and reduced myelosuppression. To bolster tumor penetration and reduce phagocytosis, we engineered a cationization-enabled transcytosis machinery by installing an ultra-pH-sensitive azepane (AZE) probe into paclitaxome and masked nanovesicle surface with a CD47 ‘self’ peptide (CD47p). The resulting CD47p/AZE–paclitaxome synchronized the co-delivery of gemcitabine or carboplatin to boost tumor inhibition and eradicate metastasis in late-stage KPC-Luc pancreatic cancer model and prevent tumor relapse and extend survival in postsurgical 4T1-Luc2 triple-negative breast cancer model in female mice. CD47p/AZE–paclitaxome also outperformed previous promising PTX nanoformulations. Finally, the series of nanoparticle modifications was applied to camptothecin, demonstrating its generalizability. ( Nat Cancer (2025). https://doi.org/10.1038/s43018-025-01029-7 ) Citation Format: Jianqin Lu. A sphingolipid-derived paclitaxel nanovesicle enhances efficacy of combination therapies in triple-negative breast cancer and pancreatic cancer abstract. In: Proceedings of the AACR Immuno-Oncology Conference (AACR IO): Discovery and Innovation in Cancer Immunology: Revolutionizing Treatment through Immunotherapy; 2026 Feb 18-21; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Immunol Res 2026;14(2 Suppl):Abstract nr B017.