A Phase 2 interventional study of External Beam Radiation Therapy and Laboratory Biomarker Analysis in Glioblastoma, Gliosarcoma and Supratentorial Glioblastoma, sponsored by Mayo Clinic. Active, not recruiting at 3 sites in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-09-22.
Sponsored by Mayo Clinic · Phase 2, Interventional, and Treatment
This phase II trial studies the side effects and how well pembrolizumab works in combination with standard therapy in treating patients with glioblastoma. Immunotherapy with monoclonal antibodies, such as pembrolizumab, may help the body's immune system attack the cancer, and may interfere with the ability of tumor cells to grow and spread. Drugs used in the chemotherapy, such as temozolomide, work in different ways to stop the growth of tumor cells, either by killing the cells, by stopping them from dividing, or by stopping them from spreading. Radiation therapy uses high energy beams to kill tumor cells and shrink tumors. Giving pembrolizumab and standard therapy comprising of temozolomide and radiation therapy may kill tumor cells.
PRIMARY OBJECTIVES:
I. To assess the safety and tolerability of pembrolizumab in combination with standard therapy (surgery, external beam radiation therapy and temozolomide [TMZ] chemotherapy) in patients with newly diagnosed glioblastoma multiforme (GBM). (Neoadjuvant [Group 1]) II. To assess the 18 month overall survival rate of pembrolizumab in combination with standard therapy (surgery, external beam radiation therapy and TMZ chemotherapy) in patients with newly diagnosed glioblastoma multiforme (GBM). (Adjuvant [Group 2])
SECONDARY OBJECTIVES:
I. To assess adverse events (AE) and toxicity profile of pembrolizumab in combination with standard therapy in patients with newly diagnosed GBM.
II. To assess time to progression in patients treated with pembrolizumab in combination with standard therapy in patients with newly diagnosed GBM. (Adjuvant only) III. To assess progression-free survival in patients treated with pembrolizumab in combination with standard therapy in patients with newly diagnosed GBM. (Adjuvant only) IV. To assess time to treatment failure in patients treated with pembrolizumab in combination with standard therapy in patients with newly diagnosed GBM. (Adjuvant only)
CORRELATIVE RESEARCH OBJECTIVES:
I. To assess the tumor PD-1/PD-L1 expression and inflammatory microenvironment profile by comparing PD-1/PD-L1 expression and T lymphocyte/monocytic infiltrates before and after administration of pembrolizumab treatment. (Neoadjuvant only) II. To assess the peripheral immunophenotype profile and GBM-associated antigen-specific T cell responses before and after receiving pembrolizumab treatment in combination with standard therapy.
OUTLINE: Patients are assigned to 1 of 2 groups.
GROUP 1:
NEOADJUVANT (CYCLE 1): Patients receive pembrolizumab intravenously (IV) over 30 minutes on day 1.
SURGERY (CYCLE 2): Patients undergo standard of care surgery within days 4-7.
CONCURRENT (CYCLE 3): Starting 21-35 days after surgery, patients receive pembrolizumab IV over 30 minutes on days 1, 22, and 43 and temozolomide orally (PO) daily on days 8-54. Patients also undergo external beam radiation therapy every 5 days per week on days 8-54.
ADJUVANT (CYCLE 4-8): Within 3-5 weeks after completing radiation therapy, patients receive pembrolizumab IV over 30 minutes on days 1, 22, and 43 and temozolomide PO daily on days 1-5 every 28 days. Treatment repeats every 63 days for up to 5 cycles in the absence of disease progression or unexpected toxicity.
GROUP 2:
CONCURRENT (CYCLE 1): Starting 21-35 days after surgery, patients receive pembrolizumab IV over 30 minutes on days 1, 22, and 43 and temozolomide PO daily on days 8-54. Patients also undergo external beam radiation therapy every 5 days per week on days 8-54.
ADJUVANT (CYCLES 2-6): Within 3-5 weeks after completing radiation therapy, patients receive pembrolizumab IV over 30 minutes on days 1, 22, and 43 of cycles 2-5 and 1 and 22 of cycle 6 (up to a total of 17 doses). Patients also receive temozolomide PO daily on days 1-5, 29-33, and 57-61 of cycles 2 and 6, days 22-26 and 50-54 of cycle 3, days 15-19 and 43-47 of cycle 4, days 8-12 and 36-40 of cycle 5. Treatment repeats every 63 days for up to 5 cycles in the absence of disease progression or unexpected toxicity.
After completion of study treatment, patients are followed up at 30 days, every 3 months until progressive disease, then every 6 months for up to 5 years.
2,132 studies on the registry are indexed under Glioblastoma; 464 are open to participants now.
This study's enrollment of 52 is above the median of 36 across 1,753 interventional studies indexed under Glioblastoma.
Browse Glioblastoma studies →Mayo Clinic is the lead sponsor of 3,269 studies on the registry; 672 are open to participants now.
Of its 452 completed or terminated interventional studies of FDA-regulated products, 321 (71%) have results posted.
Counted across the registry records on this site, refreshed daily.
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.
Histological confirmation of supratentorial glioblastoma (also known as astrocytoma grade IV, gliosarcoma)
patients only: Have an enhancing mass on magnetic resonance imaging (MRI) amenable to > 90% resection of contrast-enhancing tumor (as determined by the neurosurgeon pre-operatively) and histological diagnosis of glioblastoma or astrocytoma from a prior or surgery
Negative pregnancy test done =\< 7 days prior to registration, for persons of only (POCBP)
Willing to return to enrolling institution for follow-up (during the active monitoring phase of the study)
Exclusion Criteria:
Any of the following because this study involves an agent whose genotoxic, mutagenic and teratogenic effects on the developing fetus and newborn are unknown:
Other active =\< 5 years prior to registration
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.
Neoadjuvant treatment is given before the main treatment (usually surgery), often to shrink a tumour. Adjuvant treatment is given after it, to lower the chance of the cancer coming back.
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.
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).
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 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.
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.
How quickly the kidneys clear creatinine, a waste product, from the blood. A study may estimate it from a blood test with age, weight and sex (often by the Cockcroft–Gault formula), or measure it using blood and urine collected over a set time. Given in mL/min; higher is better.
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 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.
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.
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.
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.
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.
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.
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.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
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.
Adjuvant and neoadjuvant
Neoadjuvant treatment is given before the main treatment (usually surgery), often to shrink a tumour. Adjuvant treatment is given after it, to lower the chance of the cancer coming back.
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.
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.
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.
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.
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.
Creatinine clearance (CrCl)
How quickly the kidneys clear creatinine, a waste product, from the blood. A study may estimate it from a blood test with age, weight and sex (often by the Cockcroft–Gault formula), or measure it using blood and urine collected over a set time. Given in mL/min; higher is better.
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.
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.
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.
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.
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.
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.
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.
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.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Excipients
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
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.
NEOADJUVANT (CYCLE 1): Patients receive pembrolizumab IV over 30 minutes on day 1. SURGERY (CYCLE 2): Patients undergo standard of care surgery within days 4-7. CONCURRENT (CYCLE 3): Starting 21-35 days after surgery, patients receive pembrolizumab IV over 30 minutes on days 1, 22, and 43 and temozolomide PO daily on days 8-54. Patients also undergo external beam radiation therapy every 5 days per week on days 8-54. ADJUVANT (CYCLE 4-8): Within 3-5 weeks after completing radiation therapy, patients receive pembrolizumab IV over 30 minutes on days 1, 22, and 43 and temozolomide PO daily on days 1-5 every 28 days. Treatment repeats every 63 days for up to 5 cycles in the absence of disease progression or unexpected toxicity.
Radiation: External Beam Radiation Therapy · Other: Laboratory Biomarker Analysis · Biological: Pembrolizumab · Radiation: Radiation Therapy · Drug: Temozolomide · Procedure: Therapeutic Conventional Surgery
CONCURRENT (CYCLE 1): Starting 21-35 days after surgery, patients receive pembrolizumab IV over 30 minutes on days 1, 22, and 43 and temozolomide PO daily on days 8-54. Patients also undergo external beam radiation therapy every 5 days per week on days 8-54. ADJUVANT (CYCLES 2-6): Within 3-5 weeks after completing radiation therapy, patients receive pembrolizumab IV over 30 minutes on days 1, 22, and 43 of cycles 2-5 and 1 and 22 of cycle 6 (up to a total of 17 doses). Patients also receive temozolomide PO daily on days 1-5, 29-33, and 57-61 of cycles 2 and 6, days 22-26 and 50-54 of cycle 3, days 15-19 and 43-47 of cycle 4, days 8-12 and 36-40 of cycle 5. Treatment repeats every 63 days for up to 5 cycles in the absence of disease progression or unexpected toxicity.
Radiation: External Beam Radiation Therapy · Other: Laboratory Biomarker Analysis · Biological: Pembrolizumab · Radiation: Radiation Therapy · Drug: Temozolomide
Undergo external beam radiation therapy
Also known as: Definitive Radiation Therapy, EBRT, External Beam Radiation, External Beam Radiotherapy, External Beam RT, external radiation, External Radiation Therapy, external-beam radiation, Radiation, External Beam, Teleradiotherapy, Teletherapy, Teletherapy Radiation
Correlative studies
Given IV
Also known as: Keytruda, Lambrolizumab, MK-3475, SCH 900475
Undergo radiation therapy
Also known as: Cancer Radiotherapy, ENERGY_TYPE, Irradiate, Irradiated, Irradiation, Radiation, Radiation Therapy, NOS, Radiotherapeutics, Radiotherapy, RT, Therapy, Radiation
Given PO
Also known as: CCRG-81045, Imidazo[5,1-d]-1,2,3,5-tetrazine-8-carboxamide, 3, 4-dihydro-3-methyl-4-oxo-, M & B 39831, M and B 39831, Methazolastone, RP-46161, SCH 52365, Temcad, Temodal, Temodar, Temomedac, TMZ
Undergo surgery
Incidence of Dose Limiting Toxicities
A dose limiting toxicity DLT will be defined as an adverse event attributed (definitely, probably, or possibly) to pembrolizumab per National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE) version 4.0. Criteria: Grade 4 or higher neutropenia last at least 7 days. Grade 3 electrolyte alteration, nausea, vomiting, or diarrhea lasting at least 3 days. Grade 3 or higher neurologic toxicity. Toxicities leading to delayed treatment of at least 14 days. Inability to proceed to planned surgical resection. Inability to receive at least 75 percent of cumulative radiation dose.
Time frame: 189 days
Group 2 Overall Survival (OS) at 18 Months
Defined as the number of patients who are alive up to 18 months after beginning study therapy.
Time frame: 18 months
Incidence of Adverse Events
The overall count of participants that reported Grade 3 or higher adverse events considered at least possibly related to treatment will be calculated and reported in this section. The number of all adverse events will be tabulated and summarized in the adverse events section of this report. Group 1 dose levels are combined due to scientific interest being in the comparison of group 1, the neoadjuvant group, to group 2, the adjuvant group. Per protocol this exploratory and hypothesis generating endpoint may be analyzed by group. All patients that received the same dose level of treatment are combined to better show the adverse events encountered by the treatment population.
Time frame: 14 months
Time Until Treatment Related Grade 3+ Adverse Event
Defined as the time from treatment start date to the date of the patients first grade 3 or higher event deemed related to treatment. Group 1 dose levels are combined due to scientific interest being in the comparison of group 1, the neoadjuvant group, to group 2, the adjuvant group. Per protocol this exploratory and hypothesis generating endpoint may be analyzed by group. All patients that received the same dose level of treatment are combined to better show the adverse events encountered by the treatment population.
Time frame: 14 months
Time to Progression (Group 2)
Defined as the time from start of study treatment to disease progression. Will be assessed using the immunotherapy response assessment for neuro-oncology (iRANO) criteria.
Time frame: 36 months
Progression-free Survival (Group 2)
Defined as the time from starting study treatment to the date of disease progression or death resulting from any cause, whichever comes first. Will be assessed according to iRANO criteria.
Time frame: 36 months
Time to Treatment Failure (Group 2)
Defined as the time from beginning study therapy to documentation of disease progression, unacceptable adverse event(s), or refusal to continue participation by the patient.
Time frame: 13 months
| Milestone | Group 1 Dose Level 1 Cohort 1 | Group 1 Dose Level 1 Cohort 2 | Group 1 Dose Level 1 Cohort 3 | Group 1 Dose Level 1 Cohort 4 | Group 2 |
|---|---|---|---|---|---|
| Started | 3 | 4 | 4 | 4 | 37 |
| Completed | 3 | 3 | 3 | 3 | 35 |
| Not completed | 0 | 1 | 1 | 1 | 2 |
| Withdrew: Adverse event | 0 | 1 | 1 | 1 | 0 |
| Withdrew: Withdrawal by subject | 0 | 0 | 0 | 0 | 2 |
A dose limiting toxicity DLT will be defined as an adverse event attributed (definitely, probably, or possibly) to pembrolizumab per National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE) version 4.0. Criteria: Grade 4 or higher neutropenia last at least 7 days. Grade 3 electrolyte alteration, nausea, vomiting, or diarrhea lasting at least 3 days. Grade 3 or higher neurologic toxicity. Toxicities leading to delayed treatment of at least 14 days. Inability to proceed to planned surgical resection. Inability to receive at least 75 percent of cumulative radiation dose.
| Participants | Group 1 Dose Level 1 Cohort 1 | Group 1 Dose Level 1 Cohort 2 | Group 1 Dose Level 1 Cohort 3 | Group 1 Dose Level 1 Cohort 4 |
|---|---|---|---|---|
| Incidence of Dose Limiting Toxicities | 1 | 1 | 0 | 1 |
Defined as the number of patients who are alive up to 18 months after beginning study therapy.
| Participants | Group 2 |
|---|---|
| Group 2 Overall Survival (OS) at 18 Months | 19 |
The overall count of participants that reported Grade 3 or higher adverse events considered at least possibly related to treatment will be calculated and reported in this section. The number of all adverse events will be tabulated and summarized in the adverse events section of this report. Group 1 dose levels are combined due to scientific interest being in the comparison of group 1, the neoadjuvant group, to group 2, the adjuvant group. Per protocol this exploratory and hypothesis generating endpoint may be analyzed by group. All patients that received the same dose level of treatment are combined to better show the adverse events encountered by the treatment population.
| Participants | Group 1 | Group 2 |
|---|---|---|
| Incidence of Adverse Events | 6 | 18 |
Defined as the time from treatment start date to the date of the patients first grade 3 or higher event deemed related to treatment. Group 1 dose levels are combined due to scientific interest being in the comparison of group 1, the neoadjuvant group, to group 2, the adjuvant group. Per protocol this exploratory and hypothesis generating endpoint may be analyzed by group. All patients that received the same dose level of treatment are combined to better show the adverse events encountered by the treatment population.
| Months | Group 1 | Group 2 |
|---|---|---|
| Time Until Treatment Related Grade 3+ Adverse Event | NA (3.7 to NA) | 6.9 (4.7 to NA) |
Defined as the time from start of study treatment to disease progression. Will be assessed using the immunotherapy response assessment for neuro-oncology (iRANO) criteria.
| Months | Group 2 |
|---|---|
| Time to Progression (Group 2) | 10.7 (8.0 to 12.2) |
Defined as the time from starting study treatment to the date of disease progression or death resulting from any cause, whichever comes first. Will be assessed according to iRANO criteria.
| Months | Group 2 |
|---|---|
| Progression-free Survival (Group 2) | 10.7 (8.0 to 12.2) |
Defined as the time from beginning study therapy to documentation of disease progression, unacceptable adverse event(s), or refusal to continue participation by the patient.
| Months | Group 2 |
|---|---|
| Time to Treatment Failure (Group 2) | 8.3 (6.1 to 10.9) |
Collected over Adverse events were folllowed for 14 months and mortality was followed for 60 months. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Group 1 Dose Level 1 Cohort 1 | 3/3 (100%) | 3/3 (100%) | 3/3 (100%) |
| Group 1 Dose Level 1 Cohort 2 | 4/4 (100%) | 2/4 (50%) | 4/4 (100%) |
| Group 1 Dose Level 1 Cohort 3 | 3/4 (75%) | 2/4 (50%) | 4/4 (100%) |
| Group 1 Dose Level 1 Cohort 4 | 1/4 (25%) | 2/4 (50%) | 4/4 (100%) |
| Group 2 | 28/36 (77.8%) | 18/36 (50%) | 34/36 (94.4%) |
| Event | Group 1 Dose Level 1 Cohort 1 | Group 1 Dose Level 1 Cohort 2 | Group 1 Dose Level 1 Cohort 3 | Group 1 Dose Level 1 Cohort 4 | Group 2 |
|---|---|---|---|---|---|
| Thromboembolic eventVascular disorders | 2/3 | 0/4 | 0/4 | 0/4 | 3/36 |
| FatigueGeneral disorders | 1/3 | 0/4 | 0/4 | 0/4 | 1/36 |
| Lung infectionInfections and infestations | 1/3 | 0/4 | 0/4 | 0/4 | 0/36 |
| Generalized muscle weaknessMusculoskeletal and connective tissue disorders | 1/3 | 0/4 | 0/4 | 0/4 | 0/36 |
| DizzinessNervous system disorders | 1/3 | 0/4 | 0/4 | 0/4 | 0/36 |
| PainGeneral disorders | 0/3 | 0/4 | 1/4 | 0/4 | 0/36 |
| MeningitisInfections and infestations | 0/3 | 0/4 | 0/4 | 1/4 | 0/36 |
| Alanine aminotransferase increasedInvestigations | 0/3 | 1/4 | 1/4 | 1/4 | 3/36 |
| Aspartate aminotransferase increasedInvestigations | 0/3 | 1/4 | 0/4 | 1/4 | 3/36 |
| Blood bilirubin increasedInvestigations | 0/3 | 0/4 | 1/4 | 0/4 | 2/36 |
| Event | Group 1 Dose Level 1 Cohort 1 | Group 1 Dose Level 1 Cohort 2 | Group 1 Dose Level 1 Cohort 3 | Group 1 Dose Level 1 Cohort 4 | Group 2 |
|---|---|---|---|---|---|
| NauseaGastrointestinal disorders | 1/3 | 3/4 | 4/4 | 1/4 | 17/36 |
| FatigueGeneral disorders | 3/3 | 3/4 | 4/4 | 4/4 | 30/36 |
| Lymphocyte count decreasedInvestigations | 1/3 | 2/4 | 4/4 | 2/4 | 23/36 |
| Nervous system disorders - Oth specNervous system disorders | 3/3 | 2/4 | 0/4 | 0/4 | 1/36 |
| Rash maculo-papularSkin and subcutaneous tissue disorders | 3/3 | 2/4 | 2/4 | 3/4 | 11/36 |
| ConstipationGastrointestinal disorders | 2/3 | 0/4 | 3/4 | 1/4 | 24/36 |
| Cognitive disturbanceNervous system disorders | 2/3 | 0/4 | 3/4 | 2/4 | 18/36 |
| HeadacheNervous system disorders | 1/3 | 2/4 | 3/4 | 2/4 | 20/36 |
| VomitingGastrointestinal disorders | 2/3 | 1/4 | 1/4 | 1/4 | 9/36 |
| Alanine aminotransferase increasedInvestigations | 2/3 | 0/4 | 0/4 | 1/4 | 1/36 |
| Age, Continuous(years) | Group 1 Dose Level 1 | Group 1 Dose Level 2 | Group 1 Dose Level 3 | Group 1 Dose Level 4 | Group 2 (Pembrolizumab, Temozolomide, Radiation Therapy ) | Total |
|---|---|---|---|---|---|---|
| Mean | 58.0 ± 7.8 | 37.5 ± 7.5 | 50.3 ± 19.2 | 48.8 ± 18.7 | 57.2 ± 10.0 | 54.5 ± 12.3 |
| Sex: Female, Male(Participants) | Group 1 Dose Level 1 | Group 1 Dose Level 2 | Group 1 Dose Level 3 | Group 1 Dose Level 4 | Group 2 (Pembrolizumab, Temozolomide, Radiation Therapy ) | Total |
|---|---|---|---|---|---|---|
| Female | 2 | 1 | 3 | 3 | 9 | 18 |
| Male | 1 | 3 | 1 | 1 | 27 | 33 |
| Ethnicity (NIH/OMB)(Participants) | Group 1 Dose Level 1 | Group 1 Dose Level 2 | Group 1 Dose Level 3 | Group 1 Dose Level 4 | Group 2 (Pembrolizumab, Temozolomide, Radiation Therapy ) | Total |
|---|---|---|---|---|---|---|
| Hispanic or Latino | 0 | 0 | 0 | 0 | 2 | 2 |
| Not Hispanic or Latino | 3 | 4 | 4 | 4 | 34 | 49 |
| Unknown or Not Reported | 0 | 0 | 0 | 0 | 0 | 0 |
| Race (NIH/OMB)(Participants) | Group 1 Dose Level 1 | Group 1 Dose Level 2 | Group 1 Dose Level 3 | Group 1 Dose Level 4 | Group 2 (Pembrolizumab, Temozolomide, Radiation Therapy ) | Total |
|---|---|---|---|---|---|---|
| American Indian or Alaska Native | 0 | 0 | 0 | 0 | 0 | 0 |
| Asian | 0 | 0 | 0 | 0 | 1 | 1 |
| Native Hawaiian or Other Pacific Islander | 0 | 0 | 0 | 0 | 0 | 0 |
| Black or African American | 0 | 0 | 0 | 0 | 2 | 2 |
| White | 3 | 4 | 4 | 4 | 32 | 47 |
| More than one race | 0 | 0 | 0 | 0 | 0 | 0 |
| Unknown or Not Reported | 0 | 0 | 0 | 0 | 1 | 1 |
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Studies of the drug tested here: Pembrolizumab