FDA Grants Orphan Drug Designation to MAb-AR20.5 in Pancreatic Cancer

The FDA has granted an orphan drug designation to the IgG1k type murine monoclonal antibody MAb-AR20.5 for the treatment of patients with pancreatic cancer, according to an announcement from CanariaBio.¹

“Receiving orphan drug designation for MAb-AR20.5 is a significant milestone for CanariaBio Inc. and speaks to the potential promise of this novel therapeutic approach," Mike Na, chief executive officer of CanariaBio, stated in a news release. “We are deeply committed to advancing innovative treatments for patients with pancreatic cancer and remain hopeful that MAb-AR20.5 will offer a new lifeline for those affected.”

MAb-AR20.5 is a murine monoclonal antibody, generated against the tandem repeat protein backbone of the tumor-associated antigen, MUC1.²

In a prior phase 1 trial in patients with metastatic cancer, MAb-AR20.5 induced MUC1-specific immune responses and was well tolerated with no dose-limiting toxicities.³ Among 15 evaluable patients, human anti-mouse antibodies (HAMA) and anti-idiotypic antibodies were detected in 5 patients each, and 7 patients developed anti-MUC1 antibodies. Additionally, at a dose of 2 mg, 5 of 10 evaluable patients experienced treatment-emergent MUC1-specific T-cell responses.

Additionally, a preclinical study showed that in human MUC1 transgenic mouse models, treatment with the combination of MAb-AR20.5, anti–PD-L1, and poly-ICLC led to a significant increase over time in circulating, activated CD8-positive T cells, CD3-positive, CD4- and CD8-negative T cells, and mature dendritic cells compared with saline-treated controls.⁴

CanariaBio Inc. plans to launch clinical trials designed to assess the safety and efficacy of MAb-AR20.5 in patients with pancreatic cancer.¹

References

1. CanariaBio achieves significant milestone with FDA's orphan drug designation for MAb-AR20.5 targeting pancreatic cancer. News release. CanariaBio. August 21, 2023. Accessed August 21, 2023. https://www.prnewswire.com/news-releases/canariabio-achieves-significant-milestone-with-fdas-orphan-drug-designation-for-mab-ar20-5-targeting-pancreatic-cancer-301905407.html
2. Qi W, Schultes BC, Liu D, Kuzma M, Decker W, Madiyalakan R. Characterization of an anti-MUC1 monoclonal antibody with potential as a cancer vaccine. Hybrid Hybridomics. 2001;20(5-6):313-324. doi:10.1089/15368590152740716
3. de Bono JS, Rha SY, Stephenson J, et al. Phase I trial of a murine antibody to MUC1 in patients with metastatic cancer: evidence for the activation of humoral and cellular antitumor immunity. Ann Oncol. 2004;15(12):1825-1833. doi:10.1093/annonc/mdh472
4. Mehla K, Tremayne J, Grunkemeyer JA, et al. Combination of mAb-AR20.5, anti-PD-L1 and PolyICLC inhibits tumor progression and prolongs survival of MUC1.Tg mice challenged with pancreatic tumors. Cancer Immunol Immunother. 2018;67(3):445-457. doi:10.1007/s00262-017-2095-7