Telix Pharmaceuticals Ltd (ASX: TLX) shares are tumbling on Monday morning.
At the time of writing, the radiopharmaceuticals company's shares are down 8% to $26.35.
Why are Telix shares sinking?
Investors have been selling the company's shares today after it was dealt a blow from the US Food and Drug Administration (FDA).
According to the release, Telix has received a Complete Response Letter from the FDA for its New Drug Application (NDA) for TLX101-CDx (Pixclara). It is an investigational agent for the imaging of glioma, a rare and life-threatening brain cancer.
Telix advised that the CRL states that the FDA has completed its review of the application and has ruled that the NDA cannot be approved in its current form.
The regulator has stated that additional confirmatory clinical evidence is required to progress the application, despite a robust consultation process prior to submission and during review of the NDA.
One positive is that the FDA has not raised any concerns regarding product safety.
What next?
Telix will now request a hearing with the regulator to review the basis for the decision and is assessing clinical strategies available to augment the package in the near term.
The company described the news as "a disappointing outcome for American glioma patients."
It highlights that FET-PET is recommended medical best practice in relevant international oncology practice guidelines and is used extensively in other parts of the world. The company also points out that the FDA has granted TLX101-CDx Orphan Drug and Fast Track designation. It believes this is a tacit acknowledgement of the drug candidate's importance in addressing a significant unmet medical need and clinically demonstrating benefit over existing medical solutions.
Commenting on the news, Telix's managing director and CEO, Dr. Christian Behrenbruch, said:
We are committed to commercializing TLX101-CDx and fulfilling the unmet need to improve imaging to enable timelier and more accurate decisions for the clinical management of glioma. We have multiple go-forward pathways available to us, such as providing additional confirmatory data through several active clinical programs, including Company-led studies.
Our immediate focus is understanding the FDA's feedback and augmenting our submission with additional data to satisfy the Agency as soon as possible.
Despite this blow, there is no change to the company's financial guidance for 2025. That's because its guidance excludes revenue forecasts from unapproved products.
The company also advised that it remains committed to providing patient access to TLX101-CDx through the FDA-approved expanded access program.