Expanded Access Opens for TLX101-CDx, Investigational PET Agent in Glioma
The FDA has granted expanded access to TLX101-CDx, a promising PET imaging agent for diagnosing and monitoring glioma.
3D illustration of brain anatomy: © PIC4U - stock.adobe.com
Following the FDA’s agreement to proceed, an expanded access program for TLX101-CDx (Pixclara, 18F-floretyrosine, [18F-FET]), an investigational PET agent used for imaging progressive or recurrent glioma, has been opened.1
Making this agent commercially available in the US through the expanded access program, which is also called compassionate use, increases adult and pediatric patient access to glioma imaging, as there is currently no FDA-approved targeted amino acid PET agent for brain cancer imaging.
Further, a new drug application (NDA) for TLX101-CDx is expected to be submitted in Q3 2024.
“Amino acid PET imaging of the brain is increasingly used to supplement conventional imaging by MRI3, which for many years has been the primary clinical imaging modality in patients with glioma at all stages of disease. After treatment, MRI has several limitations, including the lack of biological specificity, dependency on blood-brain barrier disruption, and an inability to differentiate between tumor progression or recurrence from treatment-related changes. TLX101-CDx (FET-PET) shows potential to provide a more rapid and conclusive diagnosis, inform treatment decisions and deliver a new standard for the management of gliomas in the US,” said Patrick Wen, professor of neurology at Harvard Medical School and director of the Center of Neuro-Oncology at Dana-Farber Cancer Institute, in a press release.
About TLX101-CDx
TLX101-CDx is a PET imaging agent that targets LAT1 and LAT27, membrane transport proteins. TLX101-CDx can potentially be used as a companion diagnostic to TLX101, an investigational small molecule therapy for glioblastoma that is able to cross the blood-brain barrier. TLX101-CDx has made it to phase 3 studies, while the phase 1 IPAX-2 study (NCT05450744) is currently evaluating TLX101.2
“There is critical unmet need to improve the diagnosis and management of glioma, particularly in the posttreatment setting,” said Thomas A. Hope, MD, professor of radiology at the University of California San Francisco, in a press release.3 “18F-FET has the potential to help determine if a glioma is truly progressing or undergoing a treatment-induced change, known as pseudo-progression, where MRI5—the standard of care—can often be inconclusive.”
In April 2024, the FDA granted fast track designation to TLX101-CDx, which made Telix Pharmaceuticals, the agent’s manufacturer, eligible for expedited review of the NDA and more interaction with the FDA.3 In October 2020, the agent was granted an orphan drug designation from the FDA, which qualifies Telix Pharmaceuticals for potential market exclusivity for the agent, waived user fees, and tax credits.4
