FDA Grants Orphan Drug Designation to DUNP19 for Osteosarcoma

The FDA has granted an orphan drug designation (ODD) to the LRRC15 antibody DUNP19 for the treatment of patients with osteosarcoma, according to Radiopharm Theranostics.¹

“This is a very positive development for one of the latest additions to Radiopharm Theranostics’ portfolio of assets and demonstrates independent validation of the potential we saw in the DUNP19 technology,” said Riccardo Canevari, chief executive officer and managing director of Radiopharm Theranostics, in a press release. “The resulting benefits of the ODD will allow us to continue the development work of DUNP19’s inventor, H. David Ulmert, MD, PhD, with an even greater level of confidence.”

DUNP19 is a promising dual-action, LRRC15-targeted monoclonal antibody, first-in-class therapy with dual-action tumor targeting. The antibody is designed to find, internalize, and destroy cancer cells, including stromal and immune cells, as well as cells in the tumor microenvironment. These types of cells comprise over 50% of tumor masses.

LRRC15 expression is created by cancer cells and cells in the surrounding tumor microenvironment, however, it is not expressed by healthy cells. The production of LRRC15 is also high in aggressive and treatment-resistant tumors.

While osteosarcoma is a rare cancer, it is the most common primary bone cancer in children and young adults^.2 Osteosarcoma creates a variety of nuance and challenges for sarcoma care by being a genomically complex disease. Its degree of genomic instability suggests that the burden of antigens and neoantigens would provide an immunogenic potential.

Still, immune checkpoint inhibitors have not yet met these responses and ongoing studies are looking to determine the best use of antibody-based or cell therapy approaches that target these overexpressed cell-surface molecules on osteosarcoma cells.

Currently, treatment options for patients with osteosarcoma include surgery and chemotherapy. Aggressive osteosarcoma has one of the highest expressions of LRRC15.

In addition to developing DUNP19, Radiopharm Theranostics is also working with the Cu64 and Lu177 isotopes. These agents are under preclinical study.³

Additionally, Radiopharm Theranostics entered an exclusive licensing agreement with the University of California Los Angeles (UCLA) Technology Development Group in April 2022 to develop DUNP19 as an antibody-drug conjugates within radiotherapy as part of its clinical development pipeline.⁴

“We are excited to have entered into the licensing agreement with UCLA and to have addedDUNP19, a breakthrough dual action monoclonal antibody, to our clinical development pipeline,” Canevari said in a press release from April. “DUNP19 has demonstrated promise for several indications, but its potential as first-in-class therapy for osteosarcoma is particularly exciting, considering the high unmet need in the children and adolescents who typically suffer this disease.”

References

1. FDA grants orphan drug status to RAD’s DUNP19 for osteosarcoma. News release. Radiopharm Theranostics. September 9, 2022. Accessed September 9, 2022. https://bit.ly/3Rz0lbs

2. Key statistics for osteosarcoma. American Cancer Society. October 8th, 2020. Accessed: September 13, 2022. https://bit.ly/3ctNFmF

3. Our pipeline. Radiopharm Theranostics. Accessed September 9, 2022. https://www.radiopharmtheranostics.com/our-pipeline

4. Radiopharm licenses a dual action LRRC15-targeting monoclonal antibody. News release. Radiopharm Theranostics. April 4, 2022. Accessed September 9, 2022. https://bit.ly/3eF4hZS