Alpha Tau Announces Strong Overall Survival Results from Alpha DaRT Pancreatic Cancer Studies Presented at 2026 ASCO Annual Meeting - Results reinforce the potential feasibility and safety of Alpha DaRT as a one-time, mi

Alpha Tau Announces Strong Overall Survival

Results from Alpha DaRT Pancreatic Cancer Studies Presented at 2026 ASCO Annual Meeting

- Results reinforce the potential feasibility

and safety of Alpha DaRT as a one-time, minimally invasive intratumoral treatment that fits naturally into the patient journey -

- Pooled analysis of three prospective Phase

I/II studies in locally advanced or metastatic pancreatic ductal adenocarcinoma (PDAC) demonstrates encouraging median overall survival

(mOS) across chemotherapy-naive, second-line, and heavily pretreated patient populations -

-Patients treated with Alpha DaRT after 1st

line chemotherapy reached median overall survival (mOS) of 11.2 and 11.1 months in metastatic and locally advanced disease, respectively,

from the date of trial enrollment, compared to ~4 - 6 months for metastatic patients and ~ 9 months for locally advanced patients with

second-line chemotherapy, based on published historical data -

- Favorable safety profile observed across

the Alpha DaRT trials, with treatment-associated adverse events reported in 36% of subjects and Grade 3 events in 9%, with no treatment-related

deaths and no chronic toxicity; all Grade 3 events resolved -

- Following these strong survival data, Company

next turns to anticipated completion of recruitment in the multicenter U.S. IMPACT pancreatic cancer trial, which is exploring the ability

of Alpha DaRT, in combination with initiation of front-line chemotherapy, to deliver a potent and focused local dose without exacerbating

the harsh systemic side effects of standard chemotherapy -

Jerusalem, June 1, 2026 - Alpha Tau Medical

Ltd. (Nasdaq: DRTS, DRTSW) ("Alpha Tau", or the "Company"), the developer of the innovative alpha-radiation cancer

therapy Alpha DaRT , today announced positive overall survival and safety results from a pooled analysis of three prospective

Phase I/II clinical studies evaluating endoscopic ultrasound (EUS)-guided intratumoral Alpha DaRT treatment in patients with locally

advanced or metastatic pancreatic ductal adenocarcinoma (PDAC). The results were presented at the 2026 American Society of Clinical

Oncology (ASCO) Annual Meeting.

Pancreatic cancer remains one of the most lethal

of all solid tumors, with a five-year survival rate of less than 10% and survival often measured in only months for patients with advanced

disease. Treatment options are particularly limited for patients who are ineligible for chemotherapy or who have progressed through one

or more lines of systemic therapy, where historical survival is consistently poor and few effective interventions exist.

The pooled, ad-hoc analysis combined safety and

efficacy data from three studies, conducted at the Jewish General Hospital, at the Centre Hospitalier de l'Universit de Montr al

(CHUM) in Montreal, Canada, and at the Hadassah Medical Center in Jerusalem, Israel. The analysis included all patients who received the

intended Alpha DaRT treatment, with a range of patients having undergone varying lines of prior chemotherapy. Survival was analyzed using

the Kaplan-Meier method and assessed by disease stage (locally advanced versus metastatic) and by number of prior chemotherapy lines (zero,

Overall Survival Results

Note: Caution should be exercised in comparing

results from unrelated clinical studies due to differences in study designs, patient populations and other relevant factors.

Alpha DaRT-treated patients who had received

one prior line of chemotherapy achieved a median overall survival of 17.0 months in metastatic disease and 13.8 months in locally

advanced disease, from the date of initiation of the prior line of chemotherapy. Alpha DaRT as second-line therapy, measured from

study enrollment, achieved an mOS of 11.2 months in metastatic patients, while in the published literature, mOS for metastatic patients

with second-line chemotherapy is reported to be ~ 4-6 months (from initiation of second-line chemotherapy), and for the locally advanced

patients, achieved an mOS of 11.1 months, vs. ~9 months.

Alpha DaRT-treated patients who had received

two prior lines of chemotherapy - a heavily pretreated population for whom there is no established standard of care - achieved a median

overall survival of 17.1 months in locally advanced disease and 11.3 months in metastatic disease, from the date of initiation of

the second-line chemotherapy. Alpha DaRT as third-line therapy, measured from study enrollment, achieved an mOS of 7.9 months in metastatic

patients, and for the locally advanced patients, achieved an mOS of 8.8 months, while in the published literature, mOS for patients with

third-line chemotherapy is reported to be ~ 4-7 months (from the initiation of third-line chemotherapy).

Patients who were treated with Alpha DaRT and

who had not received any prior chemotherapy demonstrated mOS of 7.1 months from diagnosis in both locally advanced and metastatic diseases,

which includes mOS of 6.3 and 5.8 months, from trial enrollment, for locally advanced and metastatic patients, respectively.

Alpha DaRT was observed to have a favorable safety

profile. Treatment-associated adverse events were observed in 36% of subjects, and Grade 3 adverse events were observed in 9% of

subjects, including biliary obstruction, abdominal pain, fever, liver enzyme imbalance, and bacteremia. Importantly, there were no

treatment-related deaths, all Grade 3 adverse events resolved, and no chronic adverse events were observed. This

safety profile is especially relevant in advanced pancreatic cancer, where patients are often frail and where the cumulative toxicity

of ongoing systemic therapy can significantly compromise quality of life.

A key differentiator of Alpha DaRT is its potential

as a one-time, minimally invasive intratumoral administration, as compared to continuous oral or intravenous therapy.

Uzi Sofer, CEO of Alpha Tau, stated: "I have always

believed deeply in the potential of Alpha DaRT to be highly efficacious, but I say proudly that these results exceeded even my own

expectations, and are an outstanding extension of the interim results in these first-in-human trials that we observed last year. To

see this level of survival, achieved with a one-time treatment and without chronic side effects, in patients who today have so little

to turn to, strengthens our resolve to bring Alpha DaRT to as many of these patients as possible, as quickly as we responsibly can. These

first-in-human results are fantastic, and they demonstrate the potential of Alpha DaRT as a monotherapy, even when compared to standard-of-care

chemotherapies. And now we are even more excited about the treatment design of our U.S. IMPACT trial. In treating pancreatic cancer,

our goal is not to replace chemotherapy or other next-generation systemic therapies, our goal is to explore whether Alpha DaRT can serve

as a compelling focused local therapy and add a concurrent therapeutic boost without exacerbating the harsh systemic side effects of standard

chemotherapy regimens. We are excited about the advent of new systemic therapy options for pancreatic cancer patients, and given the safety

profile observed thus far for Alpha DaRT, we believe there is compelling rationale for exploring further combination trials in the future

with new systemic therapies as they become standard-of-care. Pancreatic cancer is one of the cruelest diagnoses, and these patients

deserve therapies that deliver not only meaningful efficacy, but also a safety profile and treatment experience that respect their quality

of life and fit into their journey rather than dominate it."

Corey Miller, MD, MSc, Director of

Therapeutic Endoscopy of the Division of Gastroenterology at the Jewish General Hospital, Assistant Professor of Medicine at McGill

University, and Principal Investigator in Canada, commented: "As the first physician in the world to deliver Alpha DaRT

into the pancreas using an endoscopic ultrasound-guided approach, seeing these results is genuinely extraordinary for me. I

treated some of the very first patients in this program, and that trajectory, from the early procedures all the way through to

receiving the survival outcome data with no observed chronic toxicity, has been truly fantastic to witness and a privilege to be a

Robert Den, MD, Chief Medical Officer of Alpha Tau, added: "These

pooled survival and safety data provide extremely encouraging reinforcement of our clinical strategy which we are moving decisively to

execute across a broad and increasingly global clinical program. Historically, local therapy has not played a big role in treating

non-resectable pancreatic cancer due to poor clinical trial results secondary to limitations on dose escalation in the pancreas in

light of the sensitive organs in the area, as well as the inability to dose chemotherapy at systemic therapy levels concurrently with

local therapy. We seek to make local therapy an integral part of the treatment of pancreatic cancer, without compromising the ability

to deliver systemic therapy concurrently. Our flagship multicenter IMPACT trial in the United States continues to advance, evaluating

Alpha DaRT in combination with chemotherapy in patients with newly diagnosed unresectable pancreatic cancer. The ACAPELLA trial in France,

evaluating Alpha DaRT alongside capecitabine in patients with locally advanced pancreatic cancer, is underway following the treatment

of its first patient. And our work at the prestigious University of Verona's Pancreas Institute is extending the program to include a

percutaneous delivery approach, broadening the range of patients who may be able to access this therapy. Together, these studies reflect

a deliberate, methodical effort to generate the rigorous evidence needed to bring Alpha DaRT to patients with one of the most significant

unmet needs in oncology."

The analysis presented is a pooled ad-hoc analysis

of three prospective Phase I/II clinical studies conducted at centers in Canada and Israel, evaluating EUS-guided intratumoral Alpha DaRT

in patients with locally advanced or metastatic pancreatic ductal adenocarcinoma across varying lines of prior chemotherapy. The analysis

included all cases that received the intended treatment. Survival analyses used the Kaplan-Meier method, measured from the time of enrollment

or from the initiation of the previous line of chemotherapy, to death, and were analyzed by disease stage and number of prior chemotherapy

lines (zero, one, or two).

Alpha DaRT (Diffusing Alpha-emitters Radiation

Therapy) is designed to enable highly potent and conformal alpha-irradiation of solid tumors by intratumoral delivery of radium-224 impregnated