A Phase 2 interventional study of Laboratory Biomarker Analysis and Pembrolizumab in Advanced Malignant Solid Neoplasm, Carcinoma of Unknown Primary and Metastatic Adrenal Gland Pheochromocytoma, sponsored by M.D. Anderson Cancer Center. Active, not recruiting at 1 site in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-07-17.
Sponsored by M.D. Anderson Cancer Center · Phase 2, Interventional, and Treatment
This phase II trial studies how well pembrolizumab works in treating patients with rare tumors that cannot be removed by surgery or have spread to other parts of the body. Monoclonal antibodies, such as pembrolizumab, may block specific proteins found on white blood cells which may strengthen the immune system and control tumor growth.
PRIMARY OBJECTIVES:
I. To obtain early indication of efficacy by evaluation of non-progression rate (NPR) at 27 weeks as defined as the percentage of patients who are alive and progression-free at 27 weeks as assessed by Response Evaluation Criteria in Solid Tumors (RECIST) version (v)1.1 or immune-related(ir)RECIST or method of tumor evaluation criteria best suitable and accepted for the tumor type evaluated in patients with advanced tumor types receiving pembrolizumab.
SECONDARY OBJECTIVES:
I. To correlate efficacy by evaluation of tumor size to programmed cell death 1 ligand 1 (PD-L1) status among patients with advanced tumor types receiving pembrolizumab.
II. To evaluate safety and tolerability of pembrolizumab in patients with advanced tumors.
III. To evaluate the percentage of patients with objective response (complete response [CR] or partial response [PR]), clinical benefit (CR, PR, or stable disease [SD] >= 4 months), progression free survival (PFS), overall survival (OS), and duration of response (DOR) as assessed by RECIST v1.1 in patients with advanced tumor types receiving pembrolizumab.
IV. To evaluate the percentage of patients with objective response (CR or PR), clinical benefit (CR, PR, or SD >= 4 months), PFS, and DOR as assessed by irRECIST in patients with advanced tumor types receiving pembrolizumab.
V. To correlate the NPR at 27 weeks (9 cycles), objective response (CR or PR), clinical benefit CR, PR, or SD >= 4 months), PFS, OS, and DOR to PD-L1 status among patients with advanced tumor types receiving pembrolizumab.
EXPLORATORY OBJECTIVES:
I. To evaluate the potential role of tumor-associated immune biomarkers for prediction of therapy effectiveness in patients with advanced tumor types receiving pembrolizumab.
II. To correlate the potential role of tumor-associated immune biomarkers for prediction of therapy effectiveness to PD-L1 status among patients with advanced tumor types receiving pembrolizumab.
III. To identify imaging characteristics associated with immunological changes in tumor following treatment with pembrolizumab.
IV. To compare tumor mutation burden and serial assessment of mutation status in biopsies obtained at baseline and progression in patients with advanced tumor types receiving pembrolizumab.
V. To evaluate patient-reported outcomes (PRO) utilizing the National Cancer Institute (NCI) Patient-Reported Outcomes of the Common Terminology Criteria for Adverse Events (PRO-CTCAE) questionnaires.
OUTLINE:
Patients receive pembrolizumab intravenously (IV) over 30 minutes on day 1. Treatment repeats every 21 days for up to 24 months in the absence of disease progression or toxicity. Patients with clinical response or disease stabilization may continue treatment for up to an additional 12 months.
After completion of study treatment, patients are followed up at 30 days and then every 12 weeks.
101 studies on the registry are indexed under Neoplasms, Unknown Primary; 19 are open to participants now.
This study's enrollment of 157 is above the median of 52 across 63 interventional studies indexed under Neoplasms, Unknown Primary.
Browse Neoplasms, Unknown Primary studies →M.D. Anderson Cancer Center is the lead sponsor of 3,047 studies on the registry; 578 are open to participants now.
Of its 612 completed or terminated interventional studies of FDA-regulated products, 409 (67%) 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.
Have one of the following advanced (unresectable and/or metastatic) solid tumor indications that has progressed following standard therapies, where standard therapies are available:
Exclusion Criteria:
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.
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.
The amount of disease can be tracked with a defined measurement, so the study can see whether it shrinks or grows. It might be a tumour measured on a scan or, in some blood cancers such as myeloma, a marker measured in blood or urine.
The criteria or the study team say which measurement counts — having no tumour visible on a scan does not by itself rule you out.
The standard rules for measuring tumours on CT or MRI scans, to tell whether a cancer is shrinking, stable or growing during treatment.
“Measurable disease per RECIST 1.1” usually means at least one tumour 10 mm or more at its longest on a CT scan, or a lymph node 15 mm or more across its short axis.
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
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 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).
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.
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.
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.
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.
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.
Cancer deposits in the brain from a cancer that started elsewhere in the body (CNS metastases include the spinal cord).
Studies differ: some leave out any brain metastases, some accept ones treated and stable for some weeks. Check what this study allows.
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.
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
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.
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.
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.
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.
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.
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.
Measurable disease
The amount of disease can be tracked with a defined measurement, so the study can see whether it shrinks or grows. It might be a tumour measured on a scan or, in some blood cancers such as myeloma, a marker measured in blood or urine.
The criteria or the study team say which measurement counts — having no tumour visible on a scan does not by itself rule you out.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
RECIST
The standard rules for measuring tumours on CT or MRI scans, to tell whether a cancer is shrinking, stable or growing during treatment.
“Measurable disease per RECIST 1.1” usually means at least one tumour 10 mm or more at its longest on a CT scan, or a lymph node 15 mm or more across its short axis.
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.
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.
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.
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.
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.
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.
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.
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.
Brain metastases
Cancer deposits in the brain from a cancer that started elsewhere in the body (CNS metastases include the spinal cord).
Studies differ: some leave out any brain metastases, some accept ones treated and stable for some weeks. Check what this study allows.
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.
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.
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.
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.
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.
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.
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.
Patients receive pembrolizumab IV over 30 minutes on day 1. Treatment repeats every 21 days for up to 24 months in the absence of disease progression or toxicity. Patients with clinical response or disease stabilization may continue treatment for up to an additional 12 months.
Other: Laboratory Biomarker Analysis · Biological: Pembrolizumab · Other: Questionnaire Administration
Correlative studies
Given IV
Also known as: Keytruda, Lambrolizumab, MK-3475, SCH 900475
Ancillary studies
Non-progression Rate (NPR) at 27 Weeks by irRECIST
Non-progression rate (NPR) at 27 weeks was defined as the percentage of efficacy evaluable patients who were alive and progression-free at 27 weeks as assessed by irRECIST Progression is defined using immune-related Response Evaluation Criteria in Solid Tumors (irRECIST), as an increase ≥ 20% (minimum 5 mm) in total measured tumor burden compared with nadir or progression of non-target lesions or new lesion
Time frame: At 27 weeks
Evaluation of Tumor Size (Objective Response by irRECIST) to PD-L1 Status (CPS ≥1)
Immune-related ORR is defined as the percentage of patients achieving a irCR or irPR based on irRECIST criteria. PD-L1 positivity was defined as Combined Positive Score ≥1. Evaluated objective response in PD-L1 positive patients Per irRECIST: Immune-related (ir) Complete Response (irCR), disappearance of all target and non-target lesions, nodal short axis diameter \<10 mm, no new lesions; irPartial Response (irPR), decrease of ≥30% in tumor burden relative to baseline, non-unequivocal progression of non-target lesions, no new lesions.
Time frame: Baseline and every 9 weeks thereafter. After 6 months, every 12 weeks at the physician's discretion, if patient has had CR, PR, or SD > 27 weeks, an average of 4 years.
Number of Patients Who Experienced Treatment-related Adverse Event (TRAE)
Per protocol, the number and percentage of patients with any treatment-related AE was summarized for all study patients combined. Patients were monitored for AE from the first day of administration of study medication through 30 days following last dose. Each AE (as defined by NCI CTCAE v4.03) was counted only once for a given subject. In the event a patient experienced repeated episodes of the same AE, then the event with the highest severity and/or strongest causal relationship to study treatment was used for purposes of tabulations.
Time frame: First day of administration of study medication through 30 days following last dose, an average of 4 years.
Objective Response Rate (ORR) Using Response Evaluation Criteria in Solid Tumors (RECIST) v1.1
ORR is defined as the percentage of patients achieving a complete response (CR) or partial response (PR) based on RECIST 1.1 criteria.
Time frame: Baseline and every 9 weeks thereafter. After 6 months, every 12 weeks at the physician's discretion, if patient has had CR, PR, or SD > 27 weeks, an average of 4 years.
Clinical Benefit Rate (CBR) Using RECIST v1.1
CBR is defined as the percentage of patients achieving a CR or PR, or stable disease (SD) ≥4 months based on RECIST 1.1 criteria.
Time frame: Baseline and every 9 weeks thereafter. After 6 months, every 12 weeks at the physician's discretion, if patient has had CR, PR, or SD > 27 weeks, an average of 4 years.
Progression-free Survival (PFS) Using RECIST v1.1
PFS was defined as the time from administration of the first dose to the first documented disease progression according to RECIST v1.1 or death due to any cause, whichever occurs first. Patients who were alive and had not experienced disease progression at the time of data cutoff were censored.
Time frame: Baseline and every 9 weeks thereafter. After 6 months, every 12 weeks at the physician's discretion, if patient has had CR, PR, or SD > 27 weeks, an average of 4 years.
Immune-related ORR Using Immune-related Response Evaluation Criteria in Solid Tumors (irRECIST)
Immune-related ORR is defined as the percentage of patients achieving a irCR or irPR based on irRECIST criteria.
Time frame: Baseline and every 9 weeks thereafter. After 6 months, every 12 weeks at the physician's discretion, if patient has had CR, PR, or SD > 27 weeks, an average of 4 years.
Immune-related Clinical Benefit Rate (CBR) Using irRECIST
Immune-related CBR is defined as the percentage of patients achieving a irCR or irPR, or irSD ≥4 months based on irRECIST criteria
Time frame: First day of administration of study medication through 30 days following last dose, an average of 4 years.
Immune-related Progression-free Survival (PFS) Using irRECIST
Immune-related PFS was defined as the time from administration of the first dose to the first documented disease progression according to irRECIST or death due to any cause, whichever occurs first. Patients who were alive and had not experienced disease progression at the time of data cutoff were censored.
Time frame: Baseline and every 9 weeks thereafter. After 6 months, every 12 weeks at the physician's discretion, if patient has had CR, PR, or SD > 27 weeks.
This is a single-center, open-label, phase II trial of pembrolizumab (MK-3475) in patients with and without programmed death-ligand 1 (PD-L1) positive advanced tumors conducted at the University of Texas MD Anderson Cancer Center
| Milestone | Cohort 1: Squamous Cell Carcinoma of the Skin | Cohort 2: Small Cell Malignancies of Nonpulmonary Origin | Cohort 3: Adrenocortical Carcinoma | Cohort 4: Medullary Renal Cell Carcinoma | Cohort 5: Carcinoma of Unknown Primary | Cohort 6: Penile Carcinoma | Cohort 7: Vascular Sarcoma | Cohort 8: Germ Cell Tumor | Cohort 9: Paraganglioma-pheochromocytoma | Cohort 10: Other Rare Tumor Histologies |
|---|---|---|---|---|---|---|---|---|---|---|
| Started | 20 | 12 | 24 | 5 | 29 | 3 | 11 | 12 | 13 | 28 |
| Completed | 3 | 0 | 2 | 0 | 3 | 0 | 0 | 0 | 2 | 3 |
| Not completed | 17 | 12 | 22 | 5 | 26 | 3 | 11 | 12 | 11 | 25 |
| Withdrew: Adverse event | 2 | 0 | 2 | 0 | 1 | 0 | 1 | 0 | 1 | 1 |
| Withdrew: Death | 0 | 0 | 0 | 0 | 1 | 0 | 1 | 0 | 0 | 1 |
| Withdrew: Lack of efficacy | 12 | 11 | 18 | 5 | 21 | 2 | 8 | 11 | 10 | 20 |
| Withdrew: Physician decision | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Withdrew: Withdrawal by subject | 1 | 0 | 0 | 0 | 3 | 0 | 1 | 1 | 0 | 1 |
| Withdrew: Participant choice | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 |
| Withdrew: Progression and exclusion from study due to changed diagnosis | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Withdrew: Progression and withdrew consent | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 |
| Withdrew: No evidence of tumor following radical surgery | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 |
Non-progression rate (NPR) at 27 weeks was defined as the percentage of efficacy evaluable patients who were alive and progression-free at 27 weeks as assessed by irRECIST Progression is defined using immune-related Response Evaluation Criteria in Solid Tumors (irRECIST), as an increase ≥ 20% (minimum 5 mm) in total measured tumor burden compared with nadir or progression of non-target lesions or new lesion
| Participants | Cohort 1: Squamous Cell Carcinoma of the Skin | Cohort 2: Small Cell Malignancies of Nonpulmonary Origin | Cohort 3: Adrenocortical Carcinoma | Cohort 4: Medullary Renal Cell Carcinoma | Cohort 5: Carcinoma of Unknown Primary | Cohort 6: Penile Carcinoma | Cohort 7: Vascular Sarcoma | Cohort 8: Germ Cell Tumor | Cohort 9: Paraganglioma-pheochromocytoma | Cohort 10: Other Rare Tumor Histologies |
|---|---|---|---|---|---|---|---|---|---|---|
| Non-progression Rate (NPR) at 27 Weeks by irRECIST | 7 | 0 | 6 | 0 | 8 | 0 | 2 | 1 | 4 | 9 |
Immune-related ORR is defined as the percentage of patients achieving a irCR or irPR based on irRECIST criteria. PD-L1 positivity was defined as Combined Positive Score ≥1. Evaluated objective response in PD-L1 positive patients Per irRECIST: Immune-related (ir) Complete Response (irCR), disappearance of all target and non-target lesions, nodal short axis diameter \<10 mm, no new lesions; irPartial Response (irPR), decrease of ≥30% in tumor burden relative to baseline, non-unequivocal progression of non-target lesions, no new lesions.
| Participants | Cohort 1: Squamous Cell Carcinoma of the Skin | Cohort 2: Small Cell Malignancies of Nonpulmonary Origin | Cohort 3: Adrenocortical Carcinoma | Cohort 4: Medullary Renal Cell Carcinoma | Cohort 5: Carcinoma of Unknown Primary | Cohort 6: Penile Carcinoma | Cohort 7: Vascular Sarcoma | Cohort 8: Germ Cell Tumor | Cohort 9: Paraganglioma-pheochromocytoma | Cohort 10: Other Rare Tumor Histologies |
|---|---|---|---|---|---|---|---|---|---|---|
| Evaluation of Tumor Size (Objective Response by irRECIST) to PD-L1 Status (CPS ≥1) | 6 | 0 | 1 | 0 | 5 | 0 | 1 | 0 | 0 | 1 |
Per protocol, the number and percentage of patients with any treatment-related AE was summarized for all study patients combined. Patients were monitored for AE from the first day of administration of study medication through 30 days following last dose. Each AE (as defined by NCI CTCAE v4.03) was counted only once for a given subject. In the event a patient experienced repeated episodes of the same AE, then the event with the highest severity and/or strongest causal relationship to study treatment was used for purposes of tabulations.
| Participants | All Patients Who Received at Least One Dose of the Drug |
|---|---|
| Number of Patients Who Experienced Treatment-related Adverse Event (TRAE) | 88 |
ORR is defined as the percentage of patients achieving a complete response (CR) or partial response (PR) based on RECIST 1.1 criteria.
| Participants | Cohort 1: Squamous Cell Carcinoma of the Skin | Cohort 2: Small Cell Malignancies of Nonpulmonary Origin | Cohort 3: Adrenocortical Carcinoma | Cohort 4: Medullary Renal Cell Carcinoma | Cohort 5: Carcinoma of Unknown Primary | Cohort 6: Penile Carcinoma | Cohort 7: Vascular Sarcoma | Cohort 8: Germ Cell Tumor | Cohort 9: Paraganglioma-pheochromocytoma | Cohort 10: Other Rare Tumor Histologies |
|---|---|---|---|---|---|---|---|---|---|---|
| Objective Response Rate (ORR) Using Response Evaluation Criteria in Solid Tumors (RECIST) v1.1 | 6 | 0 | 4 | 0 | 5 | 1 | 1 | 0 | 1 | 5 |
CBR is defined as the percentage of patients achieving a CR or PR, or stable disease (SD) ≥4 months based on RECIST 1.1 criteria.
| Participants | Cohort 1: Squamous Cell Carcinoma of the Skin | Cohort 2: Small Cell Malignancies of Nonpulmonary Origin | Cohort 3: Adrenocortical Carcinoma | Cohort 4: Medullary Renal Cell Carcinoma | Cohort 5: Carcinoma of Unknown Primary | Cohort 6: Penile Carcinoma | Cohort 7: Vascular Sarcoma | Cohort 8: Germ Cell Tumor | Cohort 9: Paraganglioma-pheochromocytoma | Cohort 10: Other Rare Tumor Histologies |
|---|---|---|---|---|---|---|---|---|---|---|
| Clinical Benefit Rate (CBR) Using RECIST v1.1 | 7 | 0 | 11 | 0 | 10 | 1 | 3 | 2 | 7 | 13 |
PFS was defined as the time from administration of the first dose to the first documented disease progression according to RECIST v1.1 or death due to any cause, whichever occurs first. Patients who were alive and had not experienced disease progression at the time of data cutoff were censored.
| months | All Patients Who Received at Least One Dose of the Drug |
|---|---|
| Progression-free Survival (PFS) Using RECIST v1.1 | 2.2 (2 to 2.7) |
Immune-related ORR is defined as the percentage of patients achieving a irCR or irPR based on irRECIST criteria.
| Participants | Cohort 1: Squamous Cell Carcinoma of the Skin | Cohort 2: Small Cell Malignancies of Nonpulmonary Origin | Cohort 3: Adrenocortical Carcinoma | Cohort 4: Medullary Renal Cell Carcinoma | Cohort 5: Carcinoma of Unknown Primary | Cohort 6: Penile Carcinoma | Cohort 7: Vascular Sarcoma | Cohort 8: Germ Cell Tumor | Cohort 9: Paraganglioma-pheochromocytoma | Cohort 10: Other Rare Tumor Histologies |
|---|---|---|---|---|---|---|---|---|---|---|
| Immune-related ORR Using Immune-related Response Evaluation Criteria in Solid Tumors (irRECIST) | 6 | 0 | 4 | 0 | 5 | 1 | 1 | 0 | 1 | 5 |
Immune-related CBR is defined as the percentage of patients achieving a irCR or irPR, or irSD ≥4 months based on irRECIST criteria
| Participants | Cohort 1: Squamous Cell Carcinoma of the Skin | Cohort 2: Small Cell Malignancies of Nonpulmonary Origin | Cohort 3: Adrenocortical Carcinoma | Cohort 4: Medullary Renal Cell Carcinoma | Cohort 5: Carcinoma of Unknown Primary | Cohort 6: Penile Carcinoma | Cohort 7: Vascular Sarcoma | Cohort 8: Germ Cell Tumor | Cohort 9: Paraganglioma-pheochromocytoma | Cohort 10: Other Rare Tumor Histologies |
|---|---|---|---|---|---|---|---|---|---|---|
| Immune-related Clinical Benefit Rate (CBR) Using irRECIST | 8 | 0 | 11 | 0 | 12 | 1 | 3 | 2 | 7 | 14 |
Immune-related PFS was defined as the time from administration of the first dose to the first documented disease progression according to irRECIST or death due to any cause, whichever occurs first. Patients who were alive and had not experienced disease progression at the time of data cutoff were censored.
| months | All Patients Who Received at Least One Dose of the Drug |
|---|---|
| Immune-related Progression-free Survival (PFS) Using irRECIST | 2.3 (2 to 3.6) |
Collected over First day of administration of study medication through 30 days following last dose.. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Participants With Advanced Rare Cancer | 114/156 (73.1%) | 72/156 (46.2%) | 84/156 (53.8%) |
| Event | Participants With Advanced Rare Cancer |
|---|---|
| Abdominal painGastrointestinal disorders | 8/156 |
| DyspneaRespiratory, thoracic and mediastinal disorders | 6/156 |
| FeverGeneral disorders | 5/156 |
| Lung infectionInfections and infestations | 5/156 |
| Pleural effusionRespiratory, thoracic and mediastinal disorders | 5/156 |
| PneumonitisRespiratory, thoracic and mediastinal disorders | 4/156 |
| AnemiaBlood and lymphatic system disorders | 3/156 |
| Back painMusculoskeletal and connective tissue disorders | 3/156 |
| FatigueGeneral disorders | 3/156 |
| Acute kidney injuryRenal and urinary disorders | 3/156 |
| Event | Participants With Advanced Rare Cancer |
|---|---|
| FatigueGeneral disorders | 55/156 |
| AnemiaBlood and lymphatic system disorders | 52/156 |
| ConstipationGastrointestinal disorders | 41/156 |
| Creatinine increasedInvestigations | 35/156 |
| Aspartate aminotransferase increasedInvestigations | 32/156 |
| Alanine aminotransferase increasedInvestigations | 31/156 |
| Rash maculo-papularSkin and subcutaneous tissue disorders | 31/156 |
| Alkaline phosphatase increasedInvestigations | 28/156 |
| NauseaGastrointestinal disorders | 28/156 |
| HypothyroidismEndocrine disorders | 27/156 |
| Age, Categorical(Participants) | Cohort 1: Squamous Cell Carcinoma of the Skin | Cohort 2: Small Cell Malignancies of Nonpulmonary Origin | Cohort 3: Adrenocortical Carcinoma | Cohort 4: Medullary Renal Cell Carcinoma | Cohort 5: Carcinoma of Unknown Primary | Cohort 6: Penile Carcinoma | Cohort 7: Vascular Sarcoma | Cohort 8: Germ Cell Tumor | Cohort 9: Paraganglioma-pheochromocytoma | Cohort 10: Other Rare Tumor Histologies | Total |
|---|---|---|---|---|---|---|---|---|---|---|---|
| <=18 years | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Between 18 and 65 years | 6 | 10 | 20 | 5 | 15 | 0 | 5 | 12 | 12 | 21 | 106 |
| >=65 years | 14 | 2 | 4 | 0 | 14 | 3 | 6 | 0 | 1 | 7 | 51 |
| Sex: Female, Male(Participants) | Cohort 1: Squamous Cell Carcinoma of the Skin | Cohort 2: Small Cell Malignancies of Nonpulmonary Origin | Cohort 3: Adrenocortical Carcinoma | Cohort 4: Medullary Renal Cell Carcinoma | Cohort 5: Carcinoma of Unknown Primary | Cohort 6: Penile Carcinoma | Cohort 7: Vascular Sarcoma | Cohort 8: Germ Cell Tumor | Cohort 9: Paraganglioma-pheochromocytoma | Cohort 10: Other Rare Tumor Histologies | Total |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Female | 3 | 7 | 14 | 1 | 21 | 0 | 4 | 2 | 5 | 19 | 76 |
| Male | 17 | 5 | 10 | 4 | 8 | 3 | 7 | 10 | 8 | 9 | 81 |
| Ethnicity (NIH/OMB)(Participants) | Cohort 1: Squamous Cell Carcinoma of the Skin | Cohort 2: Small Cell Malignancies of Nonpulmonary Origin | Cohort 3: Adrenocortical Carcinoma | Cohort 4: Medullary Renal Cell Carcinoma | Cohort 5: Carcinoma of Unknown Primary | Cohort 6: Penile Carcinoma | Cohort 7: Vascular Sarcoma | Cohort 8: Germ Cell Tumor | Cohort 9: Paraganglioma-pheochromocytoma | Cohort 10: Other Rare Tumor Histologies | Total |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Hispanic or Latino | 0 | 3 | 1 | 0 | 2 | 1 | 0 | 3 | 2 | 4 | 16 |
| Not Hispanic or Latino | 20 | 9 | 22 | 5 | 25 | 2 | 11 | 9 | 11 | 24 | 138 |
| Unknown or Not Reported | 0 | 0 | 1 | 0 | 2 | 0 | 0 | 0 | 0 | 0 | 3 |
| Race (NIH/OMB)(Participants) | Cohort 1: Squamous Cell Carcinoma of the Skin | Cohort 2: Small Cell Malignancies of Nonpulmonary Origin | Cohort 3: Adrenocortical Carcinoma | Cohort 4: Medullary Renal Cell Carcinoma | Cohort 5: Carcinoma of Unknown Primary | Cohort 6: Penile Carcinoma | Cohort 7: Vascular Sarcoma | Cohort 8: Germ Cell Tumor | Cohort 9: Paraganglioma-pheochromocytoma | Cohort 10: Other Rare Tumor Histologies | Total |
|---|---|---|---|---|---|---|---|---|---|---|---|
| American Indian or Alaska Native | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Asian | 0 | 0 | 3 | 0 | 1 | 1 | 1 | 0 | 0 | 2 | 8 |
| Native Hawaiian or Other Pacific Islander | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Black or African American | 0 | 0 | 1 | 3 | 3 | 0 | 0 | 1 | 1 | 3 | 12 |
| White | 20 | 10 | 19 | 1 | 22 | 2 | 8 | 8 | 10 | 18 | 118 |
| More than one race | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 1 |
| Unknown or Not Reported | 0 | 2 | 1 | 0 | 3 | 0 | 2 | 3 | 2 | 5 | 18 |
| Region of Enrollment(participants) | Cohort 1: Squamous Cell Carcinoma of the Skin | Cohort 2: Small Cell Malignancies of Nonpulmonary Origin | Cohort 3: Adrenocortical Carcinoma | Cohort 4: Medullary Renal Cell Carcinoma | Cohort 5: Carcinoma of Unknown Primary | Cohort 6: Penile Carcinoma | Cohort 7: Vascular Sarcoma | Cohort 8: Germ Cell Tumor | Cohort 9: Paraganglioma-pheochromocytoma | Cohort 10: Other Rare Tumor Histologies | Total |
|---|---|---|---|---|---|---|---|---|---|---|---|
| United States | 20 | 12 | 24 | 5 | 29 | 3 | 11 | 12 | 13 | 28 | 157 |
PDFs hosted by the registry, ClinicalTrials.gov.
Started Aug 2016 (actual). Primary completion is estimated for Dec 2028, 148 months after the start.
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Studies of the drug tested here: Pembrolizumab