– Podium presentation at the American Head and Neck Society (AHNS) 12th International Conference on Head and Neck Cancer to report results from a study of Alpha DaRT® in combination with pembrolizumab (Keytruda®) in elderly patients with locally advanced or metastatic head and neck squamous cell carcinoma (HNSCC) –

– Among all nine evaluable patients, the combination produced a systemic objective response rate (ORR) of 100%, including four complete responses and five partial responses, compared to just 19% ORR from historical benchmarks for pembrolizumab monotherapy in this setting –

– Median overall survival of 18.2 months and median progression-free survival of 5.4 months compare favorably with historical benchmarks for pembrolizumab monotherapy in this setting of 12.3 months and 3.2 months, respectively –

– No Alpha DaRT-associated serious adverse events were observed; the only two Alpha DaRT-associated adverse events were Grade 1 (mild) –

– Results build on foundation of Alpha DaRT monotherapy data in head and neck cancer, and lend support to Alpha Tau’s ongoing clinical strategy exploring the combination approach, which the Company continues to discuss with the U.S. FDA –

– Trial recruitment is now complete, having met the pre-specified success criterion of its Simon two-stage adaptive design: more than six patients responding to the treatment –

JERUSALEM, July 21, 2026 (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®, today announced positive results from a clinical study evaluating Alpha DaRT in combination with pembrolizumab (Keytruda®) in elderly patients with locally advanced and metastatic head and neck squamous cell carcinoma (HNSCC), in which the combination produced a 100% objective response rate and a median overall survival of 18.2 months among evaluable patients. The results are being presented in a podium presentation at the American Head and Neck Society (“AHNS”) 12th International Conference on Head and Neck Cancer, held July 18-22, 2026, in Boston, Massachusetts.

Head and neck cancer is among the most common cancers worldwide, with an estimated 890,000 new cases diagnosed globally each year, and with more than 60,000 new cases of HNSCC estimated in the United States in 2026 across the oral cavity, pharynx, and larynx. Despite treatment with curative intent, roughly half of patients with HNSCC will experience recurrence, and distant spread, when it occurs, most often involves the lung.

Since the Keytruda KEYNOTE-048 trial, pembrolizumab, with or without chemotherapy, has been the first-line standard of care for recurrent or metastatic HNSCC; however, as monotherapy in patients whose tumors express PD-L1 (Combined Positive Score, or CPS, ≥1), pembrolizumab was observed in the KEYNOTE-048 trial to produce a median overall survival of 12.3 months and an objective response rate of approximately 19%, leaving considerable room for improvement, particularly for elderly and frail patients who may not tolerate the addition of chemotherapy.

Alpha Tau’s study is a single-center, prospective, open-label, single-arm study evaluating Alpha DaRT in combination with pembrolizumab in up to 48 patients with recurrent unresectable or metastatic HNSCC and PD-L1 CPS ≥1, using a Simon two-stage adaptive design. Patients received a lead-in dose of pembrolizumab, followed by insertion of Alpha DaRT sources into a target lesion; the sources were removed ~14 days later, and patients continued on pembrolizumab per standard dosing. Tumor response was assessed systemically, i.e., in all tumors, both treated and untreated by Alpha DaRT, using Response Evaluation Criteria in Solid Tumors (RECIST v1.1), and safety was graded using the Common Terminology Criteria for Adverse Events (CTCAE v5.0). Eleven patients (four female, seven male) were recruited in total, with a mean age of 72 years (range 52-96). Two patients died prior to response evaluation, leaving nine patients evaluable for response; one died before Alpha DaRT treatment, and the other died shortly after treatment from an unrelated cardiovascular issue. With every evaluable patient responding, the trial reached the efficacy threshold built into its two-stage adaptive design, under which the study was permitted to stop for success once more than six patients responded, and enrollment was concluded on that basis.