Telix Pharmaceuticals Limited  announces that the United States (U.S.) Food and Drug Administration (FDA) has accepted the Biologics License Application (BLA) for its breakthrough investigational kidney cancer PET imaging agent TLX250-CDx  (Zircaix®, Zr-DFO-girentuximab), granted a Priority Review and provided a PDUFA date of 27 August 2025, paving the way for a U.S. commercial launch in 2025.

If approved, TLX250-CDx will become the first commercially available imaging agent to accurately and non-invasively diagnose and characterize clear cell renal cell carcinoma (ccRCC), the most common and one of the most aggressive sub-types of kidney cancer. It works by specifically binding to carbonic anhydrase IX (CAIX), a validated target protein expressed on 95% of ccRCC cells to produce images with high tumor-to-background ratio and high intra- and inter-reader consistency.

The BLA is based on Telix's successful global Phase 3 ZIRCON study, which demonstrated a sensitivity of 86%, specificity of 87% and a positive predictive value (PPV) of 93% for ccRCC, including in very small, difficult-to-detect lesions. The results of this study were published in The Lancet Oncology in September 2024, in a peer-reviewed manuscript by Professor Brian Shuch (University of California, Los Angeles, UCLA) and colleagues. The paper outlines the critical unmet need for a new, non-invasive technique that can accurately detect and differentiate ccRCC from other renal masses in patients and concluded that TLX250-CDx meets this need and 'has the potential to be practice changing.' 

Kevin Richardson, Chief Executive Officer, Precision Medicine, said, "We are delighted that the FDA has accepted this BLA as it moves us one step closer to bringing our breakthrough product to patients. We are aiming to revolutionize the management of kidney cancer, just as PSMA-PET/CT scanning has changed the management of prostate cancer. By providing a more definitive clinical diagnosis for renal masses, we believe that Zircaix will help physicians make more timely and confident patient management decisions and more quickly provide patients with a clear understanding of their disease and treatment options. Building further on Telix's successful urology franchise, we are preparing to bring this powerful precision medicine product to market in 2025."