Alpha Tau Presents Preclinical Data Demonstrating Abscopal Immune Effect in Pancreatic Murine Tumor Models at ESTRO 2024 Congress in Glasgow

- Initial data demonstrates significant reduction in distant pancreatic cancer tumor growth rate starting from three weeks after first tumor is treated with Alpha DaRT alone

- Effect seen across both Panc02 and KPC tumor models -

JERUSALEM, May 06, 2024 (GLOBE NEWSWIRE) -- Alpha Tau Medical Ltd. ("Alpha Tau", or the “Company”) (NASDAQ: DRTS, DRTSW), the developer of the innovative alpha-radiation cancer therapy Alpha DaRT, announced today the presentation of new preclinical data at the 2024 congress of the European Society for Radiotherapy and Oncology (ESTRO), currently taking place in Glasgow, UK, examining observed responses in distant untreated tumors, otherwise known as an abscopal effect, generated by Alpha DaRT in pancreatic cancer tumors in mice. The Company’s Chief Medical Officer, Dr. Robert Den, delivered a company presentation during the weekend entitled “Innovative Use of Radium-224 for Intralesional Treatment of Various Forms of Solid Tumors.” Among other things, the presentation included data from studies examining the use of Alpha DaRT to treat Panc02 and KPC pancreatic cancer tumor-bearing mice with multiple tumors.

In these preclinical studies, mice were initially inoculated intracutaneously with the Panc02 or KPC murine cell lines, and then shortly thereafter were inoculated with a secondary tumor of the same cell line in a distant site. The first tumor was treated with Alpha DaRT sources 9-10 days after inoculation, or with an inert source as a control, and the size of the secondary untreated tumor was measured every 3-4 days thereafter for 29 days. The percent change in tumor volume over time was assessed and compared between the groups with Repeated Measures ANOVA models. A statistically significant (FDR adjusted p-value < 0.05) decline in secondary tumor growth rate was found at days 21, 25 and 29 in those mice that received Alpha DaRT sources in the first tumor compared to those that received inert sources in the first tumor. A similar pattern was also observed when examining the Panc02 and KPC tumor models individually rather than grouped in one larger analysis.

Alpha Tau CEO Uzi Sofer commented, “We continue to see encouraging results that demonstrate an immune effect driven by Alpha DaRT treatment, which may offer potential benefit to patients beyond the specific tumor or tumors being treated, as we’ve already seen in previous preclinical work and in human patients where one tumor received Alpha DaRT treatment but a second, untreated tumor, had a spontaneous response. These data in pancreatic cancer preclinical models validate our plan to conduct future clinical trials examining the use of Alpha DaRT in combination with immunotherapy in patients with pancreatic cancer, and may also help explain why we have seen, and continue to see, good responses from patients in our ongoing pancreatic cancer feasibility studies in a monotherapy setting, even with only partial Alpha DaRT coverage of the tumor.”