18 and older, any sex, with Metastatic Breast Cancer. Patients with the condition only — healthy volunteers not accepted.
Results — posted to ClinicalTrials.gov
Per-arm endpoint measurements with 95% confidence intervals where reported. Source: trial results section.
Objective Response RatePrimary· Tumor measurements are repeated every 6 weeks for the first 24 weeks and then every 9 weeks thereafter. Treatment continued until disease progression or unacceptable toxicity. Treatment duration was 1 cycle. Response was evaluated up to 3 months.
The objective response rate (ORR) was defined as the proportion of participants achieving complete response (CR) or partial response (PR) outside the field of radiation based on RECIST 1.1 criteria on treatment. Per RECIST 1.1 for target lesions: CR is complete disappearance of all target lesions and PR is at least a 30% decrease in the sum of longest diameter (LD) of target lesions, taking as reference baseline sum LD. PR or better overall response assumes at a minimum incomplete response/stable disease (SD) for the evaluation of non-target lesions and absence of new lesions. Complete Respons
Group
Value
95% CI
Pembrolizumab With Radiation
0
0 – 31.25
Incidence of Grade 4 Treatment-Related ToxicitySecondary· Tumor measurements are repeated every 6 weeks for the first 24 weeks and then every 9 weeks thereafter. Treatment continued until disease progression or unacceptable toxicity. Response was evaluated up to 3 months.
All grade 4 adverse events (AE) with treatment attribution of possibly, probably or definite based on CTCAEv3 as reported on case report forms were counted. Incidence is the number of patients experiencing at least one treatment-related grade 4 AE of any type during the time of observation.
Group
Value
95% CI
Pembrolizumab With Radiation
0
Median Progression-free Survival (PFS)Secondary· Tumor measurements are repeated every 6 weeks for the first 24 weeks and then every 9 weeks thereafter. Treatment continued until disease progression or unacceptable toxicity. The maximum follow-up time is 3 months.
Progression-free survival based on the Kaplan-Meier method is defined as the duration of time from study entry to documented disease progression (PD) or death. Per RECIST 1.1 criteria: progressive disease (PD) is at least a 20% increase in the sum of longest diameter (LD) of target lesions taking as reference the smallest sum LD recorded since the treatment started or the appearance of one or more new lesions. PD for the evaluation of non-target lesions is the appearance of one or more new lesions and/or unequivocal progression of non-target lesions.
Group
Value
95% CI
Pembrolizumab With Radiation
1.4
0.4 – 2.1
Median Overall Survival (OS)Secondary· Tumor measurements are repeated every 6 weeks for the first 24 weeks and then every 9 weeks thereafter. Treatment continued until disease progression or unacceptable toxicity. The maximum follow-up time is 13 months.
OS based on the Kaplan-Meier method is defined as the time from study entry to death or censored at date last known alive.
Group
Value
95% CI
Pembrolizumab With Radiation
2.9
0.9 – 3.6
Adverse events — posted to ClinicalTrials.gov
Time frame: AE data collected every cycle (21 days) from time of the first dose of study treatment, through the study and until removal from study or death, whichever occurs first. AEs were observed up to 3 months..
Reporting threshold: 0%.
Adverse-event reports describe events observed during the trial — not all are caused by the drug.
This research study is studying radiation therapy in combination with an immunotherapy as a possible treatment for metastatic hormone receptor (HR) positive, HER2-negative breast cancer.
The interventions involved in this study are:
* Palliative Radiotherapy
* Pembrolizumab
Publications & conference data
8 peer-reviewed publications reference this trial (live from Europe PMC):
NCT07572123 — Evaluating the Addition of Maintenance Immunotherapy Compared to the Usual Treatment of Chemotherapy and Autologous Stem
· Phase 2, PHASE3
· not yet recruiting
NCT07275216 — Pembrolizumab in Combination With Chemotherapy for the Treatment of Frail Hodgkin Lymphoma Patients Ineligible for Stand
· Phase 2
· not yet recruiting
NCT07302347 — A Study of Pembrolizumab in Japanese Pediatric Participants With Solid Tumors or Lymphomas and Japanese Adult Participan
· Phase 1, PHASE2
· recruiting
NCT06724042 — Study of ISM5939 in Patients With Advanced and/or Metastatic Solid Tumors
· Phase 1
· not yet recruiting
NCT07383441 — Adding Biotherapy or Placebo to Standard Treatment for Advanced Kidney Cancer
· Phase 3
· not yet recruiting
Other recruiting trials for Metastatic Breast Cancer
Currently open trials in the same condition.
NCT07524855 — A Study of HLD-0117 in Patients With Metastatic Breast Cancer
· Phase 1
· recruiting
NCT07408089 — Study of the Kinesin Oral Molecular Degrader BBI-940 in Subjects With Advanced or Metastatic Breast Cancer
· Phase 1
· recruiting
NCT07233928 — Breast Cancer Organelle Properties and Protein Expression Atlas in the Three Immunohistochemical Subtypes of Breast Canc
· NA
· recruiting
NCT07347600 — A Study to Evaluate the Effectiveness and Safety of Inavolisib in Participants With Endocrine-resistant, PIK3CA-mutated,
· recruiting
Other Dana-Farber Cancer Institute trials
Trials by the same sponsor.
NCT07519200 — Sexual Health and Rehabilitation for Women With Metastatic Breast Cancer (SHARE-MC): An Educational Intervention
· NA
· not yet recruiting
NCT07499999 — Randomized Double-Blind Phase II Trial of Baby Exemestane Versus Baby Tamoxifen in Post-Menopausal Women at High Risk fo
· Phase 2
· not yet recruiting
NCT05825469 — Development and Testing of Nutritional Algorithms (NACHO)
· NA
· not yet recruiting
NCT07516353 — my.naviGATE: A Guide to After-Treatment Effects for Adolescents and Young Adults
· NA
· not yet recruiting
NCT07513324 — Risk-adapted Therapy in HPV-positive Oropharyngeal Cancer Using Circulating Tumor (ct) HPV DNA Profiling (ReACT 2.0)
· Phase 2
· not yet recruiting
Publications: Europe PMC API search by NCT ID, retrieved 10 June 2026
Drug + disease cross-links: matched in real time against Drug Landscape's normalised drug + company + condition tables
Sponsor: as reported to ClinicalTrials.gov by Dana-Farber Cancer Institute
Last refreshed: 27 April 2021
Drug Landscape aggregates and links these public records for informational use only. Always verify against the primary source before clinical or regulatory decisions. Canonical URL: https://druglandscape.com/trial/NCT03051672.