A Phase 1/2 interventional study of Pembrolizumab and RT Boost in Breast Cancer, sponsored by Stephen Shiao. Active, not recruiting at 1 site in United States. Open to female participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-04-20.
Sponsored by Stephen Shiao · Phase 1/2, Interventional, and Treatment
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Among 85 studies testing pembrolizumab in Breast Neoplasms — 22 open to participants now, 45 under way, 8 of them phase 3. pembrolizumab · Breast Neoplasms.
Among the 85 studies testing pembrolizumab in Breast Neoplasms, this one is the 28th largest by enrollment, is one of 16 that started in 2017, is one of 13 in phase 1/2, reaches primary completion later than 10 of the 44 other live ones, and was the 34th registered.
14,832 studies on the registry are indexed under Breast Neoplasms; 3,320 are open to participants now.
Browse Breast Neoplasms studies →22 of the 85 studies testing pembrolizumab in Breast Neoplasms are open now, in 11 countries. Recruiting first, the newest first:
London Health Sciences Centre Research Institute OR Lawson Research Institute of St. Joseph's · Sites in Canada
Ages 18+
M.D. Anderson Cancer Center · Sites in United States
Ages 18+
UNICANCER · Sites in Belgium, France
Ages 18+
UNICANCER · Sites in France, Spain
Ages 18+
M.D. Anderson Cancer Center · Sites in United States
Ages 18+
By country, each count listing its studies:
pembrolizumab: first FDA approval 2014 (KEYTRUDA), first EMA approval 2015. What it is approved for, and how studies give it, is on its page →
Of the 2,399 Breast Neoplasms studies recruiting now, 1,570 (65%) set no upper age limit and 592 (25%) stop at 75 or younger; 103 take children under 18; 215 take healthy volunteers.
This study: 18 Years and older · female · no healthy volunteers.
The full table on the hub →This tab as a report to print or save as PDF → With an account.
On this site’s reading of the record, pembrolizumab is the treatment under test here. Read study by study →
85 studies; the count open now beside each. This study's row is marked.
A study in two phases is counted once above. Listed by phase, each with its combined phases: Phase 1 21 · Phase 2 70 · Phase 3 8
First in 2010; this study’s year is marked. 16 started in 2017.
By drug class, each counting the studies that test any of its medicines:
This study's enrollment of 66 is close to the median of 72 across 10,903 interventional studies indexed under Breast Neoplasms.
Median enrollment 44 across the 85 interventional studies. Of the 32 that completed or were terminated, 20 (63%) have results posted.
This tab as a report to print or save as PDF → With an account.
5 of 85 have an industry lead sponsor. The 10 most frequent:
Stephen Shiao is the lead sponsor of 3 studies on the registry; 2 are open to participants now.
Stephen Shiao has 3 studies filed under Breast Neoplasms — fewer than ten, so there is no comparison to draw.
12 of the studies testing pembrolizumab in Breast Neoplasms that are under way reach primary completion within a year, 0 of them phase 3. Phase 3 first, then by date:
| Study | Primary completion |
|---|---|
| NCT05645380University of Kansas Medical CenterNeoadjuvant TIL- and Response-Adapted Chemoimmunotherapy for TNBC | 2026-12 |
| NCT05675579M.D. Anderson Cancer CenterA Phase II Study of Neoadjuvant Sacituzumab Govitecan and Pembrolizumab Therapy for Immunochemotherapy-resistant Early-stage Triple-negative Breast Cancer (TNBC) | 2026-12-31 |
| NCT05286437National Cancer Centre, SingaporePhase II Lenvatinib and Pembrolizumab in Endocrine Resistant Breast Cancer With Letrozole | 2026-12-31 |
| NCT04265872Baylor Research InstituteBortezomib Followed by Pembrolizumab and Cisplatin in metTNBC | 2026-12-31 |
| NCT03804944Weill Medical College of Cornell UniversityConverting HR+ Breast Cancer Into an Individualized Vaccine | 2026-12-31 |
Add all 12 to your calendar (.ics) → With an account.
Among the 85 studies testing pembrolizumab in Breast Neoplasms, from their registry updates:
This tab as a report to print or save as PDF → With an account.
This study is being done to assess the feasibility of pembrolizumab (study drug) combined with standard radiation to the tumor (tumor boost) before patients undergo standard treatment that can consist of one or more of the following: breast-conserving surgery, radiation to the entire breast/chest wall after surgery, and chemotherapy.
Study participants will receive two doses of the study drug intravenously (through the vein) before their planned breast surgery or chemotherapy. The study drug will be administered three weeks apart. At the time of the second dose, radiation to the tumor in the affected breast will be given. This type of radiation treatment is called a "tumor boost", which is a standard part of radiation therapy for breast cancer that may occur either before or after planned breast-conserving surgery. Patients will receive breast surgery or begin chemotherapy approximately six weeks after your first dose of the study drug.
With more than 1 million new cases diagnosed yearly worldwide, breast cancer is a global public health burden. Over the past decade, molecular subtyping of breast cancer has identified intrinsic subtypes that may be at enhanced risk for both local and distant recurrence. This study focuses on the immunogenicity of high-risk breast cancer subtypes that are likely to display a dense lymphocytic infiltration including including TNBC and HR+/HER2- tumors.
Immune build up via immune co-stimulatory molecules permits the ensuing immune response to strengthen and destroy cancer systemically. Thus, the effect of the anti-tumor immune response initiated by the radiation to an intact tumor by combination with checkpoint blockade is increased.
Pembrolizumab is an optimal immunotherapy agent to study, as this agent has recently been FDA approved for use in multiple tumor types. It is therefore ready to be tested for efficacy in other disease sites and in combination with other treatments.
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.
ER, PR and testing (on outside or Cedars-Sinai report), and
Screening laboratory values must meet the following criteria:
i. White blood cells (WBCs) ≥ 2000/μL ii. (ANC) ≥ 1500/μL iii. ≥ 100 x 103/μL iv. ≥ 11.0 g/dL v. Serum creatinine ≤ 2 mg/dL (or ≥ 40 ml/min) vi. ≤ 2.5 x (ULN) vii. ALT ≤ 2.5 x ULN viii. Total within normal limits (except subjects with Gilbert's syndrome, who must have total bilirubin \< 3.0 mg/dL) ix. ≤ 1.5 x ULN unless participant is receiving anticoagulant therapy as long as PT or aPTT is within therapeutic range of intended use of anticoagulant(s) x. Negative screening test xi. Negative screening tests for and . Patients with positive results that do not indicate true active or chronic infection may enroll after discussion and consensus agreement by the treating physician and principal investigator.
Exclusion Criteria:
Medical history and concurrent diseases
Prohibited Treatments and/or Therapies
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.
HER2 is a protein, made from the ERBB2 gene, that drives the growth of some cancers. A study may look for a level of the protein, extra copies of the gene, or a particular change in it.
In breast cancer, protein tests are read as HER2-positive, HER2-low or HER2-negative; other cancers use their own rules. Check which test result the study requires.
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
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.
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.
The number of neutrophils, white blood cells that help fight infection, in a given amount of blood. Too few raises the risk of infection.
It is a count, not a percentage of the white cells. Limits are written in units that mean the same: ≥ 1.5 × 10⁹/L is ≥ 1,500 per mm³ (µL). Each lab has its own reference range.
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.
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).
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
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.
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.
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.
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.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
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.
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.
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.
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.
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.
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.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Vaccines made with a weakened form of the germ, such as measles–mumps–rubella (MMR), chickenpox and yellow fever. They can be risky when the immune system is weakened. Flu injections are not live; the nasal flu spray is.
PD-1, PD-L1 and CTLA-4 are proteins that act as brakes on the immune system. Checkpoint inhibitors, such as pembrolizumab or nivolumab, block them so the immune system can attack a cancer.
PD-L1 can also be measured in a tumour sample. Some scores count stained tumour cells only (TPS); others also count certain immune cells (CPS). The study names the score and the minimum it uses.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
HER2
HER2 is a protein, made from the ERBB2 gene, that drives the growth of some cancers. A study may look for a level of the protein, extra copies of the gene, or a particular change in it.
In breast cancer, protein tests are read as HER2-positive, HER2-low or HER2-negative; other cancers use their own rules. Check which test result the study requires.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Biopsy and archival tissue
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Absolute neutrophil count (ANC)
The number of neutrophils, white blood cells that help fight infection, in a given amount of blood. Too few raises the risk of infection.
It is a count, not a percentage of the white cells. Limits are written in units that mean the same: ≥ 1.5 × 10⁹/L is ≥ 1,500 per mm³ (µL). Each lab has its own reference range.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
GFR and eGFR (kidney filtering)
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis B tests
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis C tests
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Autoimmune disease
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Live vaccines
Vaccines made with a weakened form of the germ, such as measles–mumps–rubella (MMR), chickenpox and yellow fever. They can be risky when the immune system is weakened. Flu injections are not live; the nasal flu spray is.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
PD-1, PD-L1 and checkpoint inhibitors
PD-1, PD-L1 and CTLA-4 are proteins that act as brakes on the immune system. Checkpoint inhibitors, such as pembrolizumab or nivolumab, block them so the immune system can attack a cancer.
PD-L1 can also be measured in a tumour sample. Some scores count stained tumour cells only (TPS); others also count certain immune cells (CPS). The study names the score and the minimum it uses.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Study drug plus "tumor boost" before standard of care treatment
Drug: Pembrolizumab · Radiation: RT Boost
checkpoint inhibitor
Also known as: Keytruda, MK-3475
The second dose of pembrolizumab will be given in conjunction with an RT boost, consisting of 8 Gy for 3 fractions.
Number of Patients Who do Not Necessitate a Delay in Standard of Care Treatment After Receiving the Investigational Combination of Preoperative Pembrolizumab and Radiation
Feasibility of preoperative radiation and Pembrolizumab in newly diagnosed, non-metastatic patients with triple negative breast cancer.
Time frame: 8 weeks after trial initiation
Changes in Tumor Infiltrating Lymphocyte Score (TILs)
An increase in the tumor-infiltrating lymphocyte score (TILs) as measured by Salgado criteria. An increase in TILs is an indicator of immune system engagement (range is 0-100 in percent), therefore increase indicates better outcome. A lead in with pembrolizumab alone followed by the combination of pembrolizumab with RT will allow for serial assessment of TILs. This will establish the contribution of RT to the immune response generated by pembrolizumab. The working group's consensus for Salgado criteria is that TILs may provide more biological relevant information when scored as a continuous variable. The percentage of stromal TILs is a semi quantitative parameter for this assessment (0%-100%). No formal recommendation for a clinically relevant TIL threshold(s) can be given at this stage. The consensus was that a valid methodology is currently more important than issues of thresholds for clinical use, which will be determined once a solid methodology is in place.
Time frame: 8 weeks after trial initiation
Pembrolizumab-related Adverse Events
Treatment toxicities. Number of AEs attributed to Pembrolizumab (considered at least possibly related, probably related, or related).
Time frame: 15 weeks after trial initiation
Immune-related Adverse Events
Treatment toxicities. Number of immune-related AEs (irAEs).
Time frame: Assessed up to one year post-treatment
Invasive Disease-free Survival After Preoperative Radiation and Pembrolizumab
Disease-free survival, as described from time from occurrence of surgery to time from first recurrence from or death from breast cancer
Time frame: From treatment start date until date of documented recurrence or death from breast cancer, assessed up to 19 weeks after start of treatment
Pathological Complete Response Rate
Absence of invasive disease in the breast and lymph nodes at the time of curative-intent surgery.
Time frame: From treatment start date until the time of curative-intent surgery, approximately 8 weeks.
The trial opened to accrual on 12/14/2017 with first subject enrolled on study 12/22/2017. A total of 85 patients consented, 10 subjects failed screening, 10 withdrew consent prior to starting study intervention and were replaced. 66 subjects completed study intervention but 6 were deemed unevaluable. Total target accrual of 60 subjects was met with the last subject off treatment as of 01/26/2022. Last data collection for all primary endpoints confirmed on February 6, 2025.
| Milestone | Pembrolizumab With RT Boost |
|---|---|
| Started | 66 |
| Phase 1b | 10 |
| Phase ii | 50 |
| Completed | 60 |
| Not completed | 6 |
| Withdrew: Physician decision | 1 |
| Withdrew: Unevaluable for co-primary endpoint (did not complete all required biopsies) | 5 |
Feasibility of preoperative radiation and Pembrolizumab in newly diagnosed, non-metastatic patients with triple negative breast cancer.
| Participants | Pembrolizumab With RT Boost |
|---|---|
| Number of Patients Who do Not Necessitate a Delay in Standard of Care Treatment After Receiving the Investigational Combination of Preoperative Pembrolizumab and Radiation | 36 |
An increase in the tumor-infiltrating lymphocyte score (TILs) as measured by Salgado criteria. An increase in TILs is an indicator of immune system engagement (range is 0-100 in percent), therefore increase indicates better outcome. A lead in with pembrolizumab alone followed by the combination of pembrolizumab with RT will allow for serial assessment of TILs. This will establish the contribution of RT to the immune response generated by pembrolizumab. The working group's consensus for Salgado criteria is that TILs may provide more biological relevant information when scored as a continuous variable. The percentage of stromal TILs is a semi quantitative parameter for this assessment (0%-100%). No formal recommendation for a clinically relevant TIL threshold(s) can be given at this stage. The consensus was that a valid methodology is currently more important than issues of thresholds for clinical use, which will be determined once a solid methodology is in place.
| score on a scale | PembroRT - Cohort: TNBC | PembroRT - Cohort: HR+ |
|---|---|---|
| Changes in Tumor Infiltrating Lymphocyte Score (TILs) | -6.06 ± 29.85 | -0.11 ± 8.68 |
Treatment toxicities. Number of AEs attributed to Pembrolizumab (considered at least possibly related, probably related, or related).
| Adverse Events (AEs) | Pembrolizumab With RT Boost |
|---|---|
| Pembrolizumab-related Adverse Events | 453 |
Treatment toxicities. Number of immune-related AEs (irAEs).
| Adverse Eventss (AEs) | Pembrolizumab With RT Boost |
|---|---|
| Immune-related Adverse Events | 17 |
Disease-free survival, as described from time from occurrence of surgery to time from first recurrence from or death from breast cancer
| Participants | Pembrolizumab With RT Boost |
|---|---|
| Invasive Disease-free Survival After Preoperative Radiation and Pembrolizumab | 53 |
Absence of invasive disease in the breast and lymph nodes at the time of curative-intent surgery.
| Participants | PembroRT - Cohort: TNBC | PembroRT - Cohort: HR+ |
|---|---|---|
| Pathological Complete Response Rate | 22 | 3 |
Collected over From week 1 until week 19 for all AEs, and immune-related AEs (irAEs) up until 1 year post treatment, up to 14 months.. Non-serious events are listed at a 5% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Pembrolizumab With RT Boost | 6/60 (10%) | 3/60 (5%) | 49/60 (81.7%) |
| Event | Pembrolizumab With RT Boost |
|---|---|
| Adrenal insufficiencyEndocrine disorders | 3/60 |
| HyponatremiaMetabolism and nutrition disorders | 2/60 |
| ColitisGastrointestinal disorders | 1/60 |
| Febrile neutropeniaBlood and lymphatic system disorders | 1/60 |
| FeverGeneral disorders | 1/60 |
| HypotensionVascular disorders | 1/60 |
| Lung infectionInfections and infestations | 1/60 |
| PneumonitisRespiratory, thoracic and mediastinal disorders | 1/60 |
| Rash maculo-papularSkin and subcutaneous tissue disorders | 1/60 |
| SepsisInfections and infestations | 1/60 |
| Event | Pembrolizumab With RT Boost |
|---|---|
| FatigueGeneral disorders | 49/60 |
| NauseaGastrointestinal disorders | 49/60 |
| DiarrheaGastrointestinal disorders | 29/60 |
| ConstipationGastrointestinal disorders | 26/60 |
| Peripheral sensory neuropathyNervous system disorders | 26/60 |
| Mucositis oralGastrointestinal disorders | 24/60 |
| Rash maculo-papularSkin and subcutaneous tissue disorders | 24/60 |
| HeadacheNervous system disorders | 20/60 |
| InsomniaPsychiatric disorders | 17/60 |
| MyalgiaMusculoskeletal and connective tissue disorders | 15/60 |
| Age, Categorical(Participants) | Pembrolizumab With RT Boost |
|---|---|
| <=18 years | 0 |
| Between 18 and 65 years | 45 |
| >=65 years | 15 |
| Age, Continuous(years) | Pembrolizumab With RT Boost |
|---|---|
| Median | 53 (31 to 93) |
| Age, Continuous(years) | Pembrolizumab With RT Boost |
|---|---|
| Mean | 53 ± 14 |
| Sex: Female, Male(Participants) | Pembrolizumab With RT Boost |
|---|---|
| Female | 60 |
| Male | 0 |
| Ethnicity (NIH/OMB)(Participants) | Pembrolizumab With RT Boost |
|---|---|
| Hispanic or Latino | 9 |
| Not Hispanic or Latino | 50 |
| Unknown or Not Reported | 1 |
| Race (NIH/OMB)(Participants) | Pembrolizumab With RT Boost |
|---|---|
| American Indian or Alaska Native | 0 |
| Asian | 7 |
| Native Hawaiian or Other Pacific Islander | 0 |
| Black or African American | 8 |
| White | 42 |
| More than one race | 2 |
| Unknown or Not Reported | 1 |
| Region of Enrollment(participants) | Pembrolizumab With RT Boost |
|---|---|
| United States | 60 |
PDFs hosted by the registry, ClinicalTrials.gov.
Plan to share: No
Ran from Dec 2017 to primary completion in Feb 2025, 85 months.
Of 166 non-industry phase 1/2 interventional studies under Breast Neoplasms, half reached primary completion within 67 months of starting (the median), counting those still running; a quarter within 45 and three quarters within 95. This study's 85 months is above that.
Counting every sponsor, half of 327 studies reached it within 61 months; a quarter within 45 and three quarters within 88.
How these figures are worked out, and which studies are left out of them.
This study is active, not recruiting, as verified in Apr 2026. You cannot join it, but the record below documents what was studied.
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Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Studies of the drug tested here: Pembrolizumab
Stephen Shiao