The US Food and Drug Administration (FDA) has granted approval for Alpha Tau Medical’s investigational device exemption (IDE) application to initiate a study of its Alpha diffusing alpha-emitters radiation therapy (DaRT).

This device is intended for treating recurrent cutaneous squamous cell carcinoma (cSCC) in immunocompromised patients.

The investigator-initiated, multi-centre trial is led by the Winship Cancer Institute of Emory University in Atlanta. It aims to enrol up to 28 subjects across up to eight institutions in the US.

Eligible participants include those with recurrent cSCC who are immunocompromised due to primary or secondary immunodeficiencies, with the exclusion of diabetes.

Measuring the objective response rate (ORR) to the treatment based on the best overall response will be the study’s primary efficacy objective.

Secondary efficacy objectives of the Alpha DaRT cancer therapy study will focus on progression-free survival, overall survival, and local control up to 12 months post-treatment.

Additionally, the safety objective will involve monitoring any related adverse events.

Alpha DaRT works by delivering highly potent alpha-irradiation directly into solid tumours using radium-224-impregnated sources.

As the radium decays, its short-lived daughters are said to emit high-energy alpha particles for destroying the tumour.

The limited diffusion of the alpha-emitting atoms is designed to primarily target the tumour while sparing surrounding healthy tissue.

Alpha Tau Medical CEO Uzi Sofer said: “As we continue to progress in our ReSTART multicentre pivotal trial for recurrent cutaneous SCC, a number of investigators asked about the ability to treat immunocompromised patients, who are ineligible for the ReSTART trial.

“Emory University is an important partner of ours and we are proud to work with them in initiating a trial for this population. Given the continued requests we receive from clinicians to help them treat immunocompromised patients, we are confident that a successful clinical trial can help deliver an important new potential alternative for these patients.”

Last month, the company unveiled clinical development plans for its Alpha DaRT radiotherapy device during the second quarter (Q2) financial results.