A Phase 1/2 interventional study of Pembrolizumab and Stereotactic Radiation Therapy in Glioblastoma Multiforme, sponsored by Chirag G. Patil. Recruiting at 1 site in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-09-21.
Sponsored by Chirag G. Patil · Phase 1/2, Interventional, and Treatment
The purpose of this study is to assess the safety/tolerability/feasibility of pembrolizumab and radiation therapy before surgical resection in patients with recurrent glioblastoma as defined by treatment-related AEs and the number of patients who do not necessitate a delay in surgical resection, and to assess overall survival. The secondary objectives are to assess progression free survival, and to assess the T cell clonality, CD8 T cell activation and Tumor Infiltrating Lymphocyte (TIL) score after treatment
2,132 studies on the registry are indexed under Glioblastoma; 464 are open to participants now.
This study's planned enrollment of 10 is below the median of 36 across 1,753 interventional studies indexed under Glioblastoma.
Browse Glioblastoma studies →This is the only study on the registry with Chirag G. Patil as lead sponsor.
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.
Exclusion Criteria:
Complete inclusion/exclusion criteria are detailed in the protocol.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
Drug: Pembrolizumab · Radiation: Stereotactic Radiation Therapy · Procedure: Surgical Resection
Pembrolizumab 400mg administered intravenously on Day 1, and then beginning 6 weeks post-surgery, subjects will receive 400 mg pembrolizumab every 6 weeks
Standard of care stereotactic radiation of 24 grays over 3 days, administered beginning on Day 7
Standard of care surgical resection of tumor on Day 10-28
Safety and tolerability measured by the incidence of adverse events, serious adverse events and grade 3 or above treatment related adverse events.
Safety and tolerability measured by the incidence of adverse events, serious adverse events and grade 3 or above treatment related adverse events as assessed per CTCAE, Version 5.0.
Time frame: From start of study treatment until confirmation of disease progression, intolerable toxicities, withdrawal of consent. Assessed up to 2 years.
Overall survival
From start of study treatment until death, loss to follow-up, or withdrawal of consent. Subjects who are lost to survival follow-up will not be replaced, and public records may be accessed to assess Overall Survival.
Time frame: From start of study treatment until death, loss to follow-up, or withdrawal of consent. Assessed up to 2 years.
Progression free survival
From start of study treatment until confirmation of disease progression (per iRANO Criteria), intolerable toxicities, withdrawal of consent, or up to 2 years or 18 cycles of pembrolizumab, whichever comes first.
Time frame: From start of study treatment until until confirmation of disease progression, intolerable toxicities, withdrawal of consent. Assessed up to 2 years.
Immune action
To assess the T cell clonality, CD8 T cell activation and Tumor Infiltrating Lymphocyte (TIL) score after treatment. Blood draws for research purposes performed after obtaining consent but prior to neoadjuvant pembrolizumab administration, and at the time of initiation of SRT and at the time of surgery
Time frame: At baseline, prior to stereotactic radiation therapy, and prior to surgery.
PDFs hosted by the registry, ClinicalTrials.gov.
Plan to share: No
Started Dec 2021 (actual). Primary completion is estimated for Dec 2027, 72 months after the start.
Of 84 non-industry phase 1/2 interventional studies under Glioblastoma, half reached primary completion within 73 months of starting (the median), counting those still running; a quarter within 50 and three quarters within 102. This study's planned 72 months is close to that.
Counting every sponsor, half of 137 studies reached it within 66 months; a quarter within 45 and three quarters within 100.
How these figures are worked out, and which studies are left out of them.
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Studies of the drug tested here: Pembrolizumab