ClinicalTrials.gg
RecruitingNCT05829291Updated Jun 16, 2026

Alpha Radiation Emitters Device (DaRT) for the Treatment of Liver Metastases

An interventional study of Diffusing Alpha Radiation Emitters Therapy (DaRT) in Liver Metastases, sponsored by Alpha Tau Medical LTD.. Recruiting at 1 site in Canada. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-06-16.

Sponsored by Alpha Tau Medical LTD. · Not applicable, Interventional, and Treatment

From the registry’s dates

  • Started Oct 2023; still recruiting 3 years 1 month later.
Phase
Not applicable
Study type
Interventional
Enrollment
10
Allocation
Not applicable
Ages
18 Years and older
Sex
All
01

Study summary

This is a single center study enrolling up to 10 patients. The primary objective is to Evaluate the feasibility and safety of the DaRT for the treatment of Liver Metastases. The secondary objective is to evaluate the pathological response of liver metastases according to the Modified tumor regression grade[1] and to evaluate the radiological response of liver metastases using the RECIST criteria.

Read the detailed description

This study is a Prospective, Open label, one arm, single center study to evaluate the feasibility and safety of Diffusing Alpha Radiation Emitters for the treatment of Liver Metastases .

Alpha Tau Medical proposes a unique treatment methodology for patients with liver metastases - Diffusing Alpha-emitters Radiation Therapy (DaRT) - whereby alpha particles are used to destroy solid tumors. The concept is predicated on the use of DaRT radioactive sources for radiotherapy.

DaRT is based on a nuclear decay chain originating with thorium-228 (1.91 years half-life). Outside of negligible, non-significant trace amounts, the thorium-228 remains confined to the Alpha Tau Medical manufacturing facility, and is used to generate radium-224, which is coated onto 316LVM stainless steel wires (Alpha DaRT Seeds).

The Primary endpoint of the study is : 1) Feasibility assessments of the ability to achieve full volume coverage of liver metastases volume.

2) Safety of the Alpha DaRT Seeds as therapy for liver metastases , Safety will be assessed and recorded according to CTCAE V5.

02

Conditions studied

  • Liver Metastases

Browse trials for

Keywords

  • Alpha radiation
  • Alpha emitting radiation
  • Liver Metastases
  • Brachytherapy
03

In context

Neoplasm Metastasis

4,040 studies on the registry are indexed under Neoplasm Metastasis; 886 are open to participants now.

This study's planned enrollment of 10 is below the median of 50 across 3,268 interventional studies indexed under Neoplasm Metastasis.

Browse Neoplasm Metastasis studies →

Lead sponsor

Alpha Tau Medical LTD. is the lead sponsor of 29 studies on the registry; 17 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years and older
Sexes eligible
All
Accepts healthy volunteers
No

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  1. Referred for a two staged hepatectomy following a multidisciplinary team discussion, to resect liver of colorectal cancer
  2. Targetable lesion(s) must be technically amenable for complete coverage (including margins) by the Alpha DaRT Seeds / Target(s) must be reachable for implantation
  3. Liver lesions are visible and measurable by CT according to v 1.1
  4. Age ≥ 18 years old
  5. Performance Status Scale ≤ 2
  6. Subjects' is at least 12 weeks
  7. The following laboratory parameters

    • WBC ≥ 3500/µl, granulocyte ≥ 1500/µl
    • > 85 g/L
    • Total \< 51.3 umol/L
    • count >75 X 109 /L or > 50% Prothrombin activity
    • Amylase and lipase \< 1.5 X the
    • and ALT ≤ 5 X ULN
    • (PT) international normalized ratio (INR) \< 2.3 or PT \< 6 seconds above control. Patients who are being therapeutically anticoagulated with an agent such as Coumadin or heparin will be allowed to participate provided that no prior evidence of underlying abnormality in these parameters exists
  8. Subjects are willing and able to sign an form
  9. Women of (WOCBP) will have evidence of negative pregnancy test within seven days before the Ra-224 implantation
  10. Subjects must agree to use adequate (vasectomy or barrier method of birth control) prior to study entry, for the duration of study participation and for 3 months after discontinuing therapy

Exclusion criteria

Exclusion Criteria:

  1. Concurrent cancer that is distinct in primary site or histology from colorectal cancer. Except cervical carcinoma in situ, prostate cancer with good prognosis, treated basal cell carcinoma, superficial bladder tumors (Ta, Tis \& T1). Any cancer curatively treated 3 years prior to entry is permitted.
  2. Patients undergoing systemic therapy excepting intermittent, brief use of systemic
  3. to angiography:

    • Any bleeding diathesis or coagulopathy that is not correctable by usual therapy or hemostatic agent
    • Severe peripheral vascular disease precluding catheterization
    • History of severe allergy or intolerance to contrast agents, narcotics, sedatives or atropine that cannot be managed medically
  4. Known to any of the components of the treatment.
  5. cardiovascular disease, e.g. cardiac failure of classes III-IV, uncontrolled coronary artery disease, cardiomyopathy, uncontrolled arrhythmia, uncontrolled hypertension, or history of myocardial infarction in the last 12 months.
  6. Patients with clinically significant gastrointestinal bleeding within 30 days prior to study entry.
  7. Active clinically serious infections
  8. Major surgery within 4 weeks of start of the study therapy
  9. Patients with uncontrolled intercurrent illnesses including, but not limited to an active infection requiring systemic therapy or a known psychiatric or substance abuse disorder(s) that would interfere with cooperation with the requirements of the trial or interfere with the study endpoints.
  10. Any condition that is unstable or which could jeopardize the safety of the patient and his/her compliance in the study
  11. High probability of protocol non-compliance (in opinion of investigator)
  12. Pregnant or breastfeeding women
  13. Volunteers participating in another interventional study in the past 30 days which might conflict with the endpoints of this study or the evaluation of response or toxicity of DaRT

    -

Terms in these criteria, in plain language(20)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Metastases

Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.

RECIST

The standard rules for measuring tumours on CT or MRI scans, to tell whether a cancer is shrinking, stable or growing during treatment.

“Measurable disease per RECIST 1.1” usually means at least one tumour 10 mm or more at its longest on a CT scan, or a lymph node 15 mm or more across its short axis.

ECOG performance status

A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.

0
Fully active, no restrictions.
1
Limited in strenuous activity, but walking and able to do light work, such as housework or office work.
2
Walking and able to look after yourself, but unable to work; up and about more than half of waking hours.
3
Able to look after yourself only in part; in bed or a chair more than half of waking hours.
4
Unable to look after yourself at all; in bed or a chair all day.

Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.

Life expectancy

The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.

Hemoglobin (Hb)

The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).

Bilirubin

A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.

Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.

Platelets

Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.

ULN (upper limit of normal)

The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.

“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.

ALT and AST (liver enzymes)

Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.

Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.

INR, PT and aPTT (clotting tests)

Blood tests of how long blood takes to clot. The INR is the prothrombin time (PT) put on a common scale; about 1 is usual for someone not taking a blood thinner.

Criteria often make an exception for people on a blood thinner such as warfarin, whose INR is raised on purpose.

Informed consent

Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.

You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.

Childbearing potential

Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).

Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.

Contraception

Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.

Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.

Immunosuppression

A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.

Read whether the line is about a condition or about medicines, and which medicines and doses it means.

Corticosteroids (steroids)

Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.

Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.

Contraindication

A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.

Hypersensitivity

An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.

Clinically significant

Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.

NYHA class (heart failure)

The New York Heart Association’s four classes of how much heart failure limits physical activity.

I
No limits: ordinary activity causes no undue tiredness or breathlessness.
II
Slight limits: comfortable at rest, ordinary activity causes symptoms.
III
Marked limits: comfortable at rest, less than ordinary activity causes symptoms.
IV
Symptoms even at rest; any activity makes them worse.

Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.

Brain metastases

Cancer deposits in the brain from a cancer that started elsewhere in the body (CNS metastases include the spinal cord).

Studies differ: some leave out any brain metastases, some accept ones treated and stable for some weeks. Check what this study allows.

05

Study design

Phase
Not applicable
Primary purpose
Treatment
Allocation
Not applicable
Intervention model
Single group
Masking
None (open label)
Enrollment
10 participants (estimated)

Study arms

  • Experimental
    DaRT Seeds

    Intratumoral Diffusing alpha-emitters Radiation Therapy (DaRT) Seeds

    Device: Diffusing Alpha Radiation Emitters Therapy (DaRT)

Interventions

  • DeviceDiffusing Alpha Radiation Emitters Therapy (DaRT)

    Alpha DaRT Applicators (the Alpha Needle Applicator, the Alpha Flex Applicator, and the Alpha Plant Applicator) and radioactive sources named Alpha DaRT Seeds - Ra-224 coated onto stainless steel tubes inserted into the tumor. Collectively, the Alpha DaRT Applicators and Seeds are referred to as the "Alpha DaRT Device".

06

What researchers measure

Primary outcomes

  1. Feasibility - DaRT seed placement

    Assessment of successful placement of the Alpha DaRT Seeds into liver metastases during a 2-stage hepatectomy via imaging

    Time frame: From first operation - DaRT insertion up to 24 months

  2. Safety - Adverse events

    Assess the frequency and severity of acute adverse events related to DaRT. Adverse events will be assessed and graded according to Common Terminology and Criteria for Adverse Events (CTCAE) version 5.0.

    Time frame: Up to 24 months

Secondary outcomes

  1. To evaluate the pathological response of liver metastases according to the Modified tumor regression grade 1

    Pathological response to Alpha DaRT Seeds in covered areas after surgery

    Time frame: 7-9 Weeks post DaRT insertion

  2. To evaluate the radiological response of liver metastases using the RECIST criteria .

    Radiological response to Alpha DaRT seeds implantation after the Alpha DaRT Seeds insertion procedure and prior to the second stage

    Time frame: 6-8 weeks post DaRT insertion

07

Study locations

1 of 1 sites recruiting
  • e McGill University Health Centre (MUHC)
    Montreal, Quebec H4A 3T2, Canada
    Recruiting
08

Timeline

Tracking since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reachedSimilar studies: half by the dot; the band is the middle halfHalf of similar studies reached it by the dot; the band is the middle half, from a quarter to three quarters

Started Oct 2023 (actual). Primary completion is estimated for Feb 2027, 40 months after the start.

Of 316 interventional studies with no phase under Neoplasm Metastasis, half reached primary completion within 54 months of starting (the median), counting those still running; a quarter within 28 and three quarters within 91. This study's planned 40 months is below that.

How these figures are worked out, and which studies are left out of them.

Registered
Feb 27, 2023
First posted
Apr 25, 2023
StartActual
Oct 1, 2023
Primary completionEst.
Feb 2027
CompletionEst.
Jul 2027
Last update
Jun 16, 2026
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
No changes since tracking began. The registry record was last updated on Jun 16, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
09

Registry details

Key details

Study ID
NCT05829291
Responsible party
Sponsor
First posted
Apr 25, 2023
Start date
Oct 1, 2023
Primary completion
Feb 2027 (estimated)
Completion
Jul 2027 (estimated)
Last update
Jun 16, 2026

Study contacts

Liron Dimnik
Contact
LironD@alphatau.com
+972237377000
Peter Metrakos, MD
principal investigator · McGill University Health Centre/Research Institute of the McGill University Health Centre

Oversight

FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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