Telix has announced “highly positive” top-line results from its pivotal Phase 3 ZIRCON study of its investigational kidney cancer positron emission tomography (PET) imaging agent, TLX250-CDx.
The company said the study has met its co-primary and secondary endpoints.
In the study, a total of 300 patients were dosed with TLX250-CDx. resulting in 284 evaluable patients. Each patient received a single dose of TLX250-CDx and a histological tumour sample from surgical resection was used as the truth comparator.
“The study results delivered 86 per cent sensitivity and 87 per cent specificity, exceeding the pre-determined threshold required to demonstrate the ability of TLX250-CDx to reliably detect the clear cell phenotype and provide a non-invasive method of diagnosing the presence and spread of ccRCC,” said Telix.
The study has also met the key secondary endpoint, achieving 85 per cent sensitivity and 89 per cent specificity in detecting ccRCC in tumours less than four centimetres, currently a significant clinical challenge in the diagnosis of ccRCC.
“The results mean that, for the first time, urologists and urologic oncologists may have a non-invasive way to determine if small renal masses are the clear cell phenotype, the most aggressive and common form of renal malignancy,” said the company.
TLX250-CDx has received ‘Breakthrough Designation’ from the US FDA.
According to Associate Professor Brian Shuch, the director of the Kidney Cancer Program at UCLA Institute of Urologic Oncology, “The positive result from the study is a critical step in better diagnosing clear cell renal cancer. Having an imaging product like TLX250-CDx will be so important in managing the continued increase in incidence of small renal masses and reducing the need for unnecessary invasive surgery for lesions that in the prior era were often found to be benign at the time of surgery.”
Telix said it now intends to file a biologics license application for regulatory approval with the FDA and global regulatory agencies.
Chief medical officer Dr Colin Hayward added, “The excellent sensitivity and specificity demonstrated in the ZIRCON study, validates that the CAIX target could be just as ground-breaking in ccRCC as PSMA3 and its application in PSMA-PET imaging has been for prostate cancer. It could optimise surgical intervention – particularly in the incidence of very small renal masses. These results provide confidence that TLX250-CDx is an important tool not only for initial diagnosis but potentially also for active surveillance and disease staging.”
