
Diagnosing renal masses, a growing medical dilemma
Telix’s kidney cancer portfolio targets CAIX (carbonic anhydrase IX), a scientifically validated target in ccRCC, which is the most prevalent and aggressive form of kidney cancer. CAIX is a cell surface protein that is highly expressed in clear cell renal cell carcinoma (ccRCC) and in many other solid tumours in the hypoxic tumour microenvironment. Hypoxic tumour cells are characteristic of advanced disease with typically poor treatment outcomes. Hypoxic tumours are also typically more aggressive and less responsive to current treatments, particularly immunotherapies.The detection of renal masses is increasing due to widespread use of cross-sectional imaging. Many of these are small and represent a diagnostic challenge as current imaging techniques, including ultrasound and MRI, cannot reliably distinguish benign or malignant lesions from renal cell carcinoma, leading to invasive biopsy or partial nephrectomy (kidney removal) to confirm the diagnosis. These procedures are cumbersome and often lead to complications.
We believe the highly positive result from the ZIRCON Phase III pivotal study of TLX250-CDx demonstrates the ability of TLX250-CDx to reliably detect the clear cell phenotype and provide an accurate, non-invasive method for diagnosing ccRCC.
The trial met all primary and secondary endpoints, including showing 86% sensitivity and 87% specificity and a 93% positive-predictive value, or PPV, for ccRCC across three readers. Confidence intervals exceeded expectations in all three readers showing evidence of high accuracy and consistency of interpretation. Based on these results a Biologics License Application (BLA) has been submitted to the FDA under a rolling review schema for marketing authorisation.
Kidney cancer rates have doubled in the last 50 years
430,000
people were diagnosed with kidney cancer globally in 2020
180,000
people died from kidney cancer globally in 2020
84,000
kidney / urinary biopsies or surgeries performed annually in the US
80%
of small renal masses are thought to be malignant
12%
5-year survival rate for metastatic renal cell carcinoma

Exploring CAIX as a multi-disease target
CAIX is also expressed on a number of other solid tumours including in bladder or urothelial, breast, brain, cervix, colon, oesophagus, head and neck, lung, ovarian, pancreatic and vulval cancers. It is often expressed in hypoxic (oxygenated) tumour cells. Hypoxic tumours are typically more aggressive and less responsive to current treatments, particularly immunotherapies.2
Based on this potential to target different tumour types, investigator-led studies are also in progress using these investigational assets in urothelial carcinoma or bladder cancer, triple negative breast cancer, and non-muscle invasive bladder cancer in imaging and as a stand-alone and combination therapy.