Radium-223 dichloride (223RaCl) with drug combination for patients with symptomatic bone metastases from breast cancer

2 1 1 1

What is this study about?

The study focuses on patients with symptomatic bone metastases from breast cancer. Bone metastases are sites where cancer that started in the breast has spread to the bones, causing pain and other problems. The investigational treatment is a radiopharmaceutical called Radium223 dichloride (223RaCl) given by intravenous injection. The trial also includes groups that receive the radiopharmaceutical together with standard hormone‑blocking pills such as exemestane, letrozole, or anastrozole, which are taken by mouth.

The purpose of the study is to evaluate the efficacy and safety of the radiopharmaceutical alone or in combination with these hormone blockers. Participants receive a series of injections over several months, and those in the combination arms take one of the oral pills daily. Throughout the study, doctors monitor pain levels, overall well‑being, and any side effects, and they check blood tests for an enzyme called alkaline phosphatase that can show how the bones are responding.

The trial follows each person from the first dose until the disease progresses, they stop treatment, or the study ends. Researchers record how long patients live without the disease getting worse (progression‑free survival) and overall survival, as well as quality of life, to understand the potential benefit of the new therapy.

1 signing informed consent and enrollment

after agreeing to participate, the consent form is signed and the patient is officially enrolled in the study.

2 baseline evaluation

a complete medical history is recorded, including assessment of bone pain and quality of life using standard questionnaires.

blood samples are taken to measure baseline alkaline phosphatase and other routine laboratory values.

3 first treatment administration

the first dose of radium223 dichloride is given by intravenous injection. the dose is 55 kbq/kg (kilobecquerel per kilogram).

if the patient is assigned to a combination arm, an oral aromatase inhibitor is started at the same time:

– exemestane: 25 mg taken once daily by mouth.

– letrozole: 2.5 mg taken once daily by mouth.

– anastrozole: 1 mg taken once daily by mouth.

4 subsequent radium223 injections

additional doses of radium223 dichloride are administered according to the study schedule, each dose using the same amount (55 kbq/kg) and route (intravenous).

5 regular follow‑up visits

at each scheduled visit, pain levels, quality of life, and any side effects are recorded.

blood tests, including alkaline phosphatase, are repeated to monitor changes.

the oral aromatase inhibitor, if prescribed, continues to be taken daily at the same dose.

6 completion of treatment phase

after the final planned dose of radium223 dichloride, the treatment phase ends.

final assessments of pain, quality of life, and laboratory values are performed.

7 post‑treatment follow‑up

the patient continues to be monitored for overall survival, disease progression, and any long‑term effects until the study end date.

Who Can Join the Study?

Be at least 18 years old.
Have a confirmed diagnosis of breast cancer based on examination of tissue under a microscope (histological confirmation).
Have cancer that has mainly spread to the bones, with at least two bone lesions seen on a baseline bone scan (a special X‑ray test that shows bone disease).
It is allowed to have a few cancer spots in soft parts of the body such as skin, muscle, fat, or lymph nodes (soft tissues).
Have a Performance Status score of 2 or less on the Eastern Cooperative Oncology Group (ECOG) scale, which measures how well you can carry out daily activities.
Have an absolute neutrophil count of at least 1.5 × 10⁹ per liter (a measure of a type of white blood cell that helps fight infection).
Have a platelet count of at least 100 × 10⁹ per liter and not have received a platelet transfusion in the four weeks before the first treatment dose (platelets help blood clot).
Have a hemoglobin level of at least 9.0 g/dL (100 g/L) and not have received a blood transfusion or the drug erythropoietin in the four weeks before the first treatment (hemoglobin carries oxygen in the blood).

Who Cannot Join the Study?

Having cancer that has spread to internal organs (known as visceral disease) or having other health problems that require strong cancer‑killing drugs called cytotoxic chemotherapy.
Having carcinomatous lymphangitis, which means cancer cells are spreading through the lymph vessels.
Having had any other type of cancer in the past, except for a previously treated skin cancer called basal cell carcinoma or an early‑stage bladder cancer called superficial bladder cancer (stages Ta or Tis).
Having received previous whole‑body radiation treatment that used the radioactive substances strontium‑89, samarium‑153, rhenium‑186, or rhenium‑188.

Where you can join this trial?

Verified and Recommended Sites

No sites found in this category

Verified Sites

No sites found in this category

Other Sites

Site Name	City	Country	Status
Azienda Ospedaliera Universitaria Policlinico Paolo Giaccone	Palermo	Italy

Trial status

Country	Status	Recruitment Start
Italy	Not yet recruiting	02.04.2026

Trial locations

Investigated Drugs:

Radium‑223 dichloride is a radioactive medication given through an IV. It travels to the bones and delivers tiny amounts of radiation directly to cancer cells that have spread to the bone. This helps to slow the growth of bone metastases and can reduce bone pain in patients with breast cancer.

Exemestane is a pill taken by mouth that blocks an enzyme called aromatase. By blocking this enzyme, the drug lowers the amount of estrogen in the body. Since many breast cancers need estrogen to grow, reducing estrogen can help slow the cancer. In the trial, it is used alone or together with radium‑223 to see if the combination works better.

Letrozole is another oral medication that works in the same way as exemestane. It stops the body from making estrogen, which can help control breast cancer that depends on estrogen. The study looks at how letrozole works by itself and when combined with radium‑223.

Anastrozole is also an oral aromatase‑inhibiting drug. It lowers estrogen levels to help treat hormone‑sensitive breast cancer. In this trial, anastrozole is tested as a single treatment and as part of a combination with radium‑223 to see if patients get extra benefit.

Investigated Diseases:

Breast cancer

Symptomatic bone metastases from breast cancer – Bone metastases from breast cancer are cancer cells that have spread from the original breast tumor to the bones. They often cause pain, fractures, and other bone problems. The spread usually occurs when cancer cells travel through the bloodstream or lymph system to bone tissue. Over time, the lesions can enlarge, weakening the bone and involving additional sites. Symptoms may increase as more bone areas become affected.

Trial ID:

2025-524208-31-00

Protocol code:

PA IT23 2009

Trial Phase:

Therapeutic exploratory (Phase II)

Other Trials to Consider

#1 Clinical Trials Search in Europe

Radium-223 dichloride (223RaCl) with drug combination for patients with symptomatic bone metastases from breast cancer

What is this study about?

Who Can Join the Study?

Who Cannot Join the Study?