Trial Outcomes & Findings for Atezolizumab + Stereotactic Radiation in Triple-negative Breast Cancer and Brain Metastasis (NCT NCT03483012)

Last Updated: 2025-12-09

Results Overview

Defined as time from first dose of atezolizumab (day 1 cycle 1) to progression or death due to any cause. Progression is defined according to the bi-compartmental model proposed in the RANO-BM publication, and is defined as the first detection of radiologic progression of intracranial (per RANO-BM criteria), extracranial (per RECIST 1.1 criteria), or both or unequivocal progression of non-measurable disease in the opinion of the treating physician; with each compartment (CNS and non-CNS) assessed separately

Recruitment status

ACTIVE_NOT_RECRUITING

Study phase

PHASE2

Target enrollment

6 participants

Primary outcome timeframe

Assessed from the first dose of atezolizumab until the date of first documented progression according to RANO-BM or date of death from any cause, whichever came first, for a maximum of 1.5 years

Results posted on

2025-12-09

Participant Flow

Participant milestones

Participant milestones
Measure	Atezolizumab + Stereotactic Radiosurgery (SRS) * Atezolizumab administered intravenously once every 3 weeks * Stereotactic radiosurgery (SRS) begin within 14 days after brain MRI obtained Atezolizumab: Atezolizumab is a protein that affects your immune system by blocking the PD-L1 pathway Stereotactic radiosurgery (SRS): Stereotactic radiosurgery (SRS) is a standard procedure used to treat patients with cancer in the brain. SRS uses many precisely focused radiation beams to treat tumors
Overall Study STARTED	6
Overall Study COMPLETED	0
Overall Study NOT COMPLETED	6

Reasons for withdrawal

Reasons for withdrawal
Measure	Atezolizumab + Stereotactic Radiosurgery (SRS) * Atezolizumab administered intravenously once every 3 weeks * Stereotactic radiosurgery (SRS) begin within 14 days after brain MRI obtained Atezolizumab: Atezolizumab is a protein that affects your immune system by blocking the PD-L1 pathway Stereotactic radiosurgery (SRS): Stereotactic radiosurgery (SRS) is a standard procedure used to treat patients with cancer in the brain. SRS uses many precisely focused radiation beams to treat tumors
Overall Study Lack of Efficacy	6

Baseline Characteristics

Atezolizumab + Stereotactic Radiation in Triple-negative Breast Cancer and Brain Metastasis

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Atezolizumab + Stereotactic Radiosurgery (SRS) n=6 Participants * Atezolizumab administered intravenously once every 3 weeks * Stereotactic radiosurgery (SRS) begin within 14 days after brain MRI obtained Atezolizumab: Atezolizumab is a protein that affects your immune system by blocking the PD-L1 pathway Stereotactic radiosurgery (SRS): Stereotactic radiosurgery (SRS) is a standard procedure used to treat patients with cancer in the brain. SRS uses many precisely focused radiation beams to treat tumors
Age, Continuous	46 years n=4 Participants
Age, Customized Age category · <50	4 Participants n=4 Participants
Age, Customized Age category · >=50	2 Participants n=4 Participants
Sex: Female, Male Female	6 Participants n=4 Participants
Sex: Female, Male Male	0 Participants n=4 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants n=4 Participants
Race (NIH/OMB) Asian	0 Participants n=4 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=4 Participants
Race (NIH/OMB) Black or African American	0 Participants n=4 Participants
Race (NIH/OMB) White	5 Participants n=4 Participants
Race (NIH/OMB) More than one race	0 Participants n=4 Participants
Race (NIH/OMB) Unknown or Not Reported	1 Participants n=4 Participants
Eastern Cooperative Oncology Group (ECOG) performance status 0-Fully active, able to carry on pre-disease performance without restriction	5 Participants n=4 Participants
Eastern Cooperative Oncology Group (ECOG) performance status 1-Restricted in strenuous physical activity but able to perform work of a light or sedentary nature	1 Participants n=4 Participants
Stage at initial diagnosis I- Cancer has spread to other tissue in small area	1 Participants n=4 Participants
Stage at initial diagnosis II- Tumor is 20-50mm with some lymph node involvement, or tumor is >50mm with no nodal involvement	4 Participants n=4 Participants
Stage at initial diagnosis Not IV but otherwise unknown- Non-metastatic but stage otherwise unknown	1 Participants n=4 Participants
Disease-free interval (interval from primary diagnosis date to metastatic diagnosis date) <2 years	2 Participants n=4 Participants
Disease-free interval (interval from primary diagnosis date to metastatic diagnosis date) >=2 years	4 Participants n=4 Participants
Hormone receptor status of primary tumor ER positive/PR negative	1 Participants n=4 Participants
Hormone receptor status of primary tumor ER and PR negative	5 Participants n=4 Participants
Hormone receptor status of metastatic tumor ER and PR negative	1 Participants n=4 Participants
Hormone receptor status of metastatic tumor Not done	5 Participants n=4 Participants
HER-2 status of primary tumor (IHC) Negative (0,1+)	4 Participants n=4 Participants
HER-2 status of primary tumor (IHC) Equivocal (2+)	1 Participants n=4 Participants
HER-2 status of primary tumor (IHC) Not done	1 Participants n=4 Participants
HER-2 status of primary tumor (ISH) Negative (copy number <4 and HER2/CEP17 ratio <2.0)	4 Participants n=4 Participants
HER-2 status of primary tumor (ISH) Not done	2 Participants n=4 Participants
Measurable disease by RECIST 1.1 at baseline Yes	5 Participants n=4 Participants
Measurable disease by RECIST 1.1 at baseline No	1 Participants n=4 Participants
Prior adjuvant or neoadjuvant endocrine therapy Yes	3 Participants n=4 Participants
Prior adjuvant or neoadjuvant endocrine therapy No	3 Participants n=4 Participants
Prior lines of chemotherapy for metastasis or recurrence 0 lines	2 Participants n=4 Participants
Prior lines of chemotherapy for metastasis or recurrence 1 line	3 Participants n=4 Participants
Prior lines of chemotherapy for metastasis or recurrence >=2 lines	1 Participants n=4 Participants

PRIMARY outcome

Timeframe: Assessed from the first dose of atezolizumab until the date of first documented progression according to RANO-BM or date of death from any cause, whichever came first, for a maximum of 1.5 years

Outcome measures

Outcome measures
Measure	Atezolizumab + Stereotactic Radiosurgery (SRS) n=6 Participants * Atezolizumab administered intravenously once every 3 weeks * Stereotactic radiosurgery (SRS) begin within 14 days after brain MRI obtained Atezolizumab: Atezolizumab is a protein that affects your immune system by blocking the PD-L1 pathway Stereotactic radiosurgery (SRS): Stereotactic radiosurgery (SRS) is a standard procedure used to treat patients with cancer in the brain. SRS uses many precisely focused radiation beams to treat tumors
Progression-Free Survival	5.8 weeks Interval 4.1 to Insufficient sample size/number of events

SECONDARY outcome

Timeframe: Assessed from the first dose of atezolizumab until disease progression, intercurrent illness, unacceptable toxicity, noncompliance/withdrawal, or general/specific worsening of condition, for a maximum of 1.5 years

Defined as the percentage of patients achieving a complete response (complete disappearance of all target and non-target lesions; no new lesions) or partial response (at least 30% decrease in the sum of the diameters of target lesions; persistence of one or more non-target lesion(s) and/or maintenance of tumor marker level above the normal limits \[i.e., "non-CR/non-PD" in non-target lesions\]; and no new lesions) based on RECIST 1.1

Outcome measures

Outcome measures
Measure	Atezolizumab + Stereotactic Radiosurgery (SRS) n=6 Participants * Atezolizumab administered intravenously once every 3 weeks * Stereotactic radiosurgery (SRS) begin within 14 days after brain MRI obtained Atezolizumab: Atezolizumab is a protein that affects your immune system by blocking the PD-L1 pathway Stereotactic radiosurgery (SRS): Stereotactic radiosurgery (SRS) is a standard procedure used to treat patients with cancer in the brain. SRS uses many precisely focused radiation beams to treat tumors
Extracranial Objective Response Rate	0 percentage of patients Interval 0.0 to 45.9

SECONDARY outcome

Timeframe: Assessed from the first dose of atezolizumab to the date of death from any cause or date last known alive, for a maximum of 3.8 years

Defined as the time from first dose of atezolizumab (day 1 cycle 1) to death from any cause. Patients who are alive at the end of the study are censored at the date of last known alive.

Outcome measures

Outcome measures
Measure	Atezolizumab + Stereotactic Radiosurgery (SRS) n=6 Participants * Atezolizumab administered intravenously once every 3 weeks * Stereotactic radiosurgery (SRS) begin within 14 days after brain MRI obtained Atezolizumab: Atezolizumab is a protein that affects your immune system by blocking the PD-L1 pathway Stereotactic radiosurgery (SRS): Stereotactic radiosurgery (SRS) is a standard procedure used to treat patients with cancer in the brain. SRS uses many precisely focused radiation beams to treat tumors
Overall Survival	42.4 weeks Interval 15.7 to Insufficient sample size/number of events

Adverse Events

Atezolizumab + Stereotactic Radiosurgery (SRS)

Serious events: 2 serious events

Other events: 5 other events

Deaths: 5 deaths

Serious adverse events

Serious adverse events
Measure	Atezolizumab + Stereotactic Radiosurgery (SRS) n=6 participants at risk * Atezolizumab administered intravenously once every 3 weeks * Stereotactic radiosurgery (SRS) begin within 14 days after brain MRI obtained Atezolizumab: Atezolizumab is a protein that affects your immune system by blocking the PD-L1 pathway Stereotactic radiosurgery (SRS): Stereotactic radiosurgery (SRS) is a standard procedure used to treat patients with cancer in the brain. SRS uses many precisely focused radiation beams to treat tumors
Nervous system disorders Intracranial hemorrhage	16.7% 1/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.
Respiratory, thoracic and mediastinal disorders Dyspnea	16.7% 1/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.
Respiratory, thoracic and mediastinal disorders Pleural effusion	16.7% 1/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.

Other adverse events

Other adverse events
Measure	Atezolizumab + Stereotactic Radiosurgery (SRS) n=6 participants at risk * Atezolizumab administered intravenously once every 3 weeks * Stereotactic radiosurgery (SRS) begin within 14 days after brain MRI obtained Atezolizumab: Atezolizumab is a protein that affects your immune system by blocking the PD-L1 pathway Stereotactic radiosurgery (SRS): Stereotactic radiosurgery (SRS) is a standard procedure used to treat patients with cancer in the brain. SRS uses many precisely focused radiation beams to treat tumors
Endocrine disorders Cushingoid	16.7% 1/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.
Gastrointestinal disorders Abdominal pain	16.7% 1/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.
Gastrointestinal disorders Bloating	16.7% 1/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.
Gastrointestinal disorders Constipation	16.7% 1/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.
Gastrointestinal disorders Dyspepsia	16.7% 1/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.
Gastrointestinal disorders Nausea	33.3% 2/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.
Gastrointestinal disorders Vomiting	16.7% 1/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.
General disorders Fatigue	50.0% 3/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.
General disorders Fever	33.3% 2/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.
General disorders Flu like symptoms	16.7% 1/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.
General disorders Non-cardiac chest pain	16.7% 1/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.
General disorders Pain	16.7% 1/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.
Infections and infestations Pharyngitis	16.7% 1/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.
Infections and infestations Urinary tract infection	16.7% 1/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.
Infections and infestations Vaginal infection	16.7% 1/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.
Investigations Alanine aminotransferase increased	16.7% 1/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.
Investigations Alkaline phosphatase increased	16.7% 1/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.
Investigations Aspartate aminotransferase increased	33.3% 2/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.
Investigations Weight loss	16.7% 1/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.
Metabolism and nutrition disorders Anorexia	33.3% 2/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.
Musculoskeletal and connective tissue disorders Generalized muscle weakness	33.3% 2/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.
Musculoskeletal and connective tissue disorders Muscle weakness left-sided	16.7% 1/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.
Musculoskeletal and connective tissue disorders Myalgia	16.7% 1/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.
Nervous system disorders Ataxia	16.7% 1/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.
Nervous system disorders Cognitive disturbance	16.7% 1/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.
Nervous system disorders Headache	16.7% 1/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.
Nervous system disorders Paresthesia	16.7% 1/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.
Nervous system disorders Seizure	16.7% 1/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.
Reproductive system and breast disorders Vaginal discharge	16.7% 1/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.
Respiratory, thoracic and mediastinal disorders Cough	50.0% 3/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.
Respiratory, thoracic and mediastinal disorders Dyspnea	16.7% 1/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.
Respiratory, thoracic and mediastinal disorders Respiratory, thoracic and mediastinal disorders	16.7% 1/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.
Skin and subcutaneous tissue disorders Rash maculo-papular	16.7% 1/6 • Adverse event data were collected on the first day of each treatment cycle, at the end of treatment, and up to 30 days post-end of treatment, for up to a maximum of 1.8 years. Death events were assessed for up to a maximum of 3.8 years.

Additional Information

Sara Tolaney, MD, MPH

Dana-Farber Cancer Institute

Phone: 617-632-5743

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place