Esta página se tradujo automáticamente y no se garantiza la precisión de la traducción. por favor refiérase a versión inglesa para un texto fuente.

Radioterapia del cuerpo ablativo estereotáctico (SABR) con mantenimiento de la terapia sistémica versus la elección de la terapia sistémica de los médicos para el cáncer de mama negativo de ER-Positivo oligoprogresivo, HER-2 II (AVATARII)

15 de septiembre de 2026 actualizado por: Peter MacCallum Cancer Centre, Australia

The goal of this clinical trial is to assess Stereotactic Ablative Radiotherapy (SABR) as a method to delay a change in systemic therapy in patients with oligoprogressive ER-positive, HER2-negative advanced breast cancer. The main question it aims to answer is to assess whether the addition of SABR to continuation of first line endocrine therapy and CDK 4/6 inhibitor (Arm A) to patients with oligoprogressive ER-positive, HER2-negative advanced breast cancer could have longer time to treatment failure (TTF) in comparison to physician choice of systemic treatment (Arm B) in patients who had progressed first line.

The treatment strategy in Arm A is to maintain patients on current endocrine therapy and CDK 4/6 inhibitor, controlling localised progressing sites of disease with SABR. Treatment strategy in Arm B is to maintain disease control with physician's choice of systemic therapy alone.

Descripción general del estudio

Descripción detallada

AVATAR II is a phase II multicentre open label, randomised trial. Following informed consent, eligible patients with ER-positive, HER2-negative advanced breast cancer receiving an ET (either AI or selective estrogen receptor degrader in combination with a CDK 4/6 inhibitor with newly diagnosed OPD amenable to SABR will be randomised to either:

Arm A: SABR to all known sites of OPD with continuation of first line therapy ET and CDK 4/6 inhibitor Arm B: Physician's choice of systemic treatment

Patients must have evidence of radiological response to ET and CDK 4/6 inhibitor for a minimum of six months prior to randomisation.

All patients will be followed up for 3 years after the last patient has been randomised.

Tipo de estudio

Intervencionista

Inscripción (Estimado)

74

Fase

  • No aplica

Contactos y Ubicaciones

Esta sección proporciona los datos de contacto de quienes realizan el estudio e información sobre dónde se lleva a cabo este estudio.

Estudio Contacto

Copia de seguridad de contactos de estudio

  • Nombre: A/Prof Michelle White
  • Número de teléfono: +61 3 9928 8111
  • Correo electrónico: michelle@mcc.net.au

Criterios de participación

Los investigadores buscan personas que se ajusten a una determinada descripción, denominada criterio de elegibilidad. Algunos ejemplos de estos criterios son el estado de salud general de una persona o tratamientos previos.

Criterio de elegibilidad

Edades elegibles para estudiar

18 años y mayores (Adulto, Adulto Mayor)

Acepta Voluntarios Saludables

No

Géneros elegibles para el estudio

Todos

Descripción

INCLUSION CRITERIA

Patients will be eligible for inclusion in this trial if all the following criteria apply:

  1. Patient has signed the AVATAR-II Patient Information and Consent Form (PICF)

  2. Male or female, ≥ 18 years of age at the time signing consent

  3. Patients with histologically proven ER-positive, HER2-negative advanced breast cancer receiving an ET in combination with a CDK 4/6 inhibitor. Biopsy of metastatic disease if technically feasible but not mandatory

  4. Patients must have evidence of extracranial metastatic disease, with no evidence of uncontrolled intracranial metastases. (Controlled intracranial metastases are defined as stable disease on repeat CT imaging performed at least one month apart.)

  5. Patients must have evidence of radiological response to ET and CDK 4/6 inhibitor for a minimum of six months prior to randomisation.

    Note: Patient must have ongoing stability/response in at least one lesion at the time of randomisation.

  6. Evidence of new or existing OPD, as determined by the Investigator and defined according to RECIST1.1, via CT on a per-lesion basis (between 1-5 metastases, including the primary) as follows:

    • At least a 20% increase in the diameter of a lesion, taking as reference the smallest diameter on a previous CT scan with an absolute increase of at least 5mm
    • Appearance of a new lesion(s) Note: A new lesion can be identified using various imaging modalities, such as PET-CT or WBBS, as long as the lesion is visible on serial CT scans.
  7. For patients with liver or lung metastases, maximum of 3 oligoprogressive lesions in single organ

  8. All OPD must be amenable to SABR, as per the radiotherapy guidelines in section 11.1 and Appendix 4 and 5 of Protocol v2.3 dated 20Feb2026

  9. ECOG performance status 0-2

  10. Life expectancy ≥ 6 months

  11. Clinician and patient are willing to continue current line of therapy if randomised to Arm A

  12. Patient is able to complete QoL questionnaires, and other assessments required as part of the study

EXCLUSION CRITERIA

Patients will not be eligible for inclusion in this trial if any of the following criteria apply:

  1. Is pregnant or lactating at the time of randomisation
  2. Evidence of more than one clone of metastatic disease e.g., a patient with both ER-positive and triple negative clones of disease and ER-negative and/or HER2-positive disease would be excluded from the study
  3. Evidence of leptomeningeal disease
  4. Evidence of malignant cord compression
  5. Evidence of lesion within femoral bone requiring surgical fixation
  6. Patients with risk of bone fracture are not candidate for SABR (Appendix 4 and 5 of Protocol v2.3 dated 20Feb2026)
  7. Previous chemotherapy for metastatic disease. Note: chemotherapy for primary breast cancer is allowed
  8. Contraindications to radiotherapy
  9. Any condition deeming the patient unsuitable to comply with the study
  10. Substantial overlap with previously treated area. Reirradiation is permitted with the condition that the combined plan adheres to the specific dose constraints outlined in this protocol. It is advised to use biological effective dose (BED) calculations to correlate previous doses with the tolerance doses documented in the protocol
  11. Evidence of progression in more than 5 lesions
  12. Prior SABR delivered for oligoprogressive disease with the intent of delaying a change in systemic therapy.

Plan de estudios

Esta sección proporciona detalles del plan de estudio, incluido cómo está diseñado el estudio y qué mide el estudio.

¿Cómo está diseñado el estudio?

Detalles de diseño

  • Propósito principal: Tratamiento
  • Asignación: Aleatorizado
  • Modelo Intervencionista: Asignación paralela
  • Enmascaramiento: Ninguno (etiqueta abierta)

Armas e Intervenciones

Grupo de participantes/brazo
Intervención / Tratamiento
Experimental: SABR to all known sites of oligoprogressive disease with continuation of first line therapy

SABR to all known sites of oligoprogressive disease with continuation of first line therapy ET + CDK4/6i

Stereotactic Ablative Radiotherapy

Comparador activo: Physician's choice of systemic treatment

Physician's choice of systemic treatment does not mandate a change in systemic therapy, however, SABR is not permitted for management in this arm

Physician's choice of systemic therapy does not mandate a change in systemic therapy, however, SABR is not permitted for management in this arm

¿Qué mide el estudio?

Medidas de resultado primarias

Medida de resultado
Medida Descripción
Periodo de tiempo
Primary Outcome Measure
Periodo de tiempo: Time from randomisation to progression of disease resulting in a failure of treatment strategy or death by any cause assessed until withdrawal of consent, death, or 3 years after the last patient has been randomised, whichever is earlier.

The primary endpoint of this study is to measure the time to treatment failure between Arm A and Arm B.

Treatment failure is defined as time from randomisation to progression of disease resulting in a failure of treatment strategy or death by any cause.

Progression, will be determined by the Investigator, using the Response Evaluation Criteria in Solid Tumors, Version 1.1. (RECIST1.1; Appendix 2) (33) as a guide.

The treatment strategy in Arm A is to maintain patients on current ET and CDK 4/6 inhibitor, controlling localised progressing sites of disease with SABR. Treatment strategy in Arm B is to maintain disease control with physician's choice systemic therapy alone.

Time from randomisation to progression of disease resulting in a failure of treatment strategy or death by any cause assessed until withdrawal of consent, death, or 3 years after the last patient has been randomised, whichever is earlier.

Medidas de resultado secundarias

Medida de resultado
Medida Descripción
Periodo de tiempo
Secondary Objective 1
Periodo de tiempo: Time from randomisation to progression of disease resulting in a failure of treatment strategy or death by any cause assessed until withdrawal of consent, death, or 3 years after the last patient has been randomised, whichever is earlier.

To compare PFS; PFS is assessed from randomisation to the date of the first evidence of progression or death by any cause. Progression will be assessed by the treating clinician as part of standard-of-care practice, using RECIST 1.1 as a guide or based on clinical progression.

Time from randomisation to progression of disease resulting in a failure of treatment strategy or death by any cause assessed until withdrawal of consent, death, or 3 years after the last patient has been randomised, whichever is earlier.
Secondary Objective 2
Periodo de tiempo: Time from randomisation to progression of disease resulting in a failure of treatment strategy or death by any cause assessed until withdrawal of consent, death, or 3 years after the last patient has been randomised, whichever is earlier.

To compare progression-free survival 2 (PFS-2); PFS-2 is assessed from randomisation to the date of progression on next line of systemic anti-cancer treatment or death by any cause.

Time from randomisation to progression of disease resulting in a failure of treatment strategy or death by any cause assessed until withdrawal of consent, death, or 3 years after the last patient has been randomised, whichever is earlier.
Secondary Objective 3
Periodo de tiempo: Time from randomisation to progression of disease resulting in a failure of treatment strategy or death by any cause assessed until withdrawal of consent, death, or 3 years after the last patient has been randomised, whichever is earlier.

To compare PFS of next line of treatment (2nd PFS); 2nd PFS is assessed from failure of treatment strategy to progression on next line of systemic anti-cancer treatment or date of death by any cause.

Time from randomisation to progression of disease resulting in a failure of treatment strategy or death by any cause assessed until withdrawal of consent, death, or 3 years after the last patient has been randomised, whichever is earlier.
Secondary Objective 4
Periodo de tiempo: Time from randomisation to progression of disease resulting in a failure of treatment strategy or death by any cause assessed until withdrawal of consent, death, or 3 years after the last patient has been randomised, whichever is earlier.

To compare OS; OS is assessed from randomisation to the date of death by any cause.

Time from randomisation to progression of disease resulting in a failure of treatment strategy or death by any cause assessed until withdrawal of consent, death, or 3 years after the last patient has been randomised, whichever is earlier.
Secondary Objective 5
Periodo de tiempo: Time from randomisation to progression of disease resulting in a failure of treatment strategy or death by any cause assessed until withdrawal of consent, death, or 3 years after the last patient has been randomised, whichever is earlier.

To compare treatment related adverse events (TRAEs); TRAEs are adverse events assessed using the Common Terminology for Adverse Events Version 5.0 (CTCAE v5.0) considered possibly, probably, or definitely related to treatment (systemic therapy or SABR)

Time from randomisation to progression of disease resulting in a failure of treatment strategy or death by any cause assessed until withdrawal of consent, death, or 3 years after the last patient has been randomised, whichever is earlier.
Secondary Objective 6
Periodo de tiempo: Time from randomisation to progression of disease resulting in a failure of treatment strategy or death by any cause assessed until withdrawal of consent, death, or 3 years after the last patient has been randomised, whichever is earlier.

To compare the QoL using the FACT-B total score: Area under the curve (AUC) of the FACT-B Total score from baseline to 48 weeks

Time from randomisation to progression of disease resulting in a failure of treatment strategy or death by any cause assessed until withdrawal of consent, death, or 3 years after the last patient has been randomised, whichever is earlier.

Colaboradores e Investigadores

Aquí es donde encontrará personas y organizaciones involucradas en este estudio.

Investigadores

  • Investigador principal: A/Prof Steven David, Peter MacCallum Cancer Centre, Australia

Publicaciones y enlaces útiles

La persona responsable de ingresar información sobre el estudio proporciona voluntariamente estas publicaciones. Estos pueden ser sobre cualquier cosa relacionada con el estudio.

Publicaciones Generales

Fechas de registro del estudio

Estas fechas rastrean el progreso del registro del estudio y los envíos de resultados resumidos a ClinicalTrials.gov. Los registros del estudio y los resultados informados son revisados ​​por la Biblioteca Nacional de Medicina (NLM) para asegurarse de que cumplan con los estándares de control de calidad específicos antes de publicarlos en el sitio web público.

Fechas importantes del estudio

Inicio del estudio (Estimado)

1 de noviembre de 2026

Finalización primaria (Estimado)

1 de noviembre de 2032

Finalización del estudio (Estimado)

1 de noviembre de 2032

Fechas de registro del estudio

Enviado por primera vez

8 de diciembre de 2024

Primero enviado que cumplió con los criterios de control de calidad

12 de marzo de 2025

Publicado por primera vez (Actual)

18 de marzo de 2025

Actualizaciones de registros de estudio

Última actualización publicada (Actual)

18 de septiembre de 2026

Última actualización enviada que cumplió con los criterios de control de calidad

15 de septiembre de 2026

Última verificación

1 de septiembre de 2026

Más información

Términos relacionados con este estudio

Plan de datos de participantes individuales (IPD)

¿Planea compartir datos de participantes individuales (IPD)?

NO

Descripción del plan IPD

Not contractually obliged but it may be considered

Información sobre medicamentos y dispositivos, documentos del estudio

Estudia un producto farmacéutico regulado por la FDA de EE. UU.

No

Estudia un producto de dispositivo regulado por la FDA de EE. UU.

No

Esta información se obtuvo directamente del sitio web clinicaltrials.gov sin cambios. Si tiene alguna solicitud para cambiar, eliminar o actualizar los detalles de su estudio, comuníquese con register@clinicaltrials.gov. Tan pronto como se implemente un cambio en clinicaltrials.gov, también se actualizará automáticamente en nuestro sitio web. .

Suscribir