A Phase 2 interventional study of Pembrolizumab in Cancer of Unknown Primary Site, sponsored by Imperial College London. Completed at 3 sites in United Kingdom. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-05-04.
Sponsored by Imperial College London · Phase 2, Interventional, and Treatment
Abbreviated Title : CUPem Clinical Indication : A Phase II, Two-Stage, Trial of Pembrolizumab in Cancer of unknown primary Trial Type : Single Arm, non-randomised; Two-stage; Hypothesis generating Type of control : None Route of administration : IV Trial Blinding : N/A
Treatment Groups :Two cohorts:
(i) First Cohort: One or more lines of prior therapy (ii) Second Cohort: First Line untreated CUP patients Number of trial subjects : i) First Cohort: 20 ii) Second Cohort: 57 Eligibility Criteria : The Eligibility Criteria are the same as used in the A trial of chemotherapy for cancer of unknown primary (CUP-ONE) trial in the United Kingdom (UK), please see below.
Estimated recruitment period : 2 years Estimated duration of trial : 3.9 years including set up, recruitment, follow up and close down.
Duration of Participation : Cohort 1 = 6-8 months; Cohort 2 = 8-18 months Estimated average length of treatment per patient =6 months
An open label, non-randomised, single arm, sequential phase (two sequential cohorts) study, evaluating the preliminary efficacy of Pembrolizumab in Cancer of unknown Primary (CUP).
Cohort 1:
Cohort 1 will enrol a maximum of 20 patients, who have had at least one prior line / regimen of chemotherapy (at least 2 cycles) appropriate for CUP and who have not had a RECIST response to first-line chemotherapy, or are progressing after an initial response, or are treatment intolerant to first-line chemotherapy, due to unacceptable toxicity.
As soon as there has been one documented response in cohort 1, the study then proceeds to enrol cohort 2 in parallel. Cohort 2 will not be initiated, if have been no cohort 1 (0/20) patients who have benefitted and 20 cohort 1 patients have completed at least 12 weeks of therapy. Benefit for this study is defined as either a RECIST or irRECIST response; stable disease for a minimum of 12 weeks. This allows a go / no-go decision to proceed/ not proceed to enrolling cohort 2 by the trial management group
Cohort 2:
Cohort 2 will enrol a maximum of 57 patients who are chemo-naïve (first-line setting) for CUP*, with a PS 0-2. Benefit for this study is defined as either a RECIST or irRECIST response or stable disease at 12 weeks.
*Previous chemotherapy for other cancers is allowed
For both cohorts, patients will undergo screening procedures during a standard 28-days time window from initiation of the study, under standard Good Clinical Practice (GCP) and informed consent. Restaging will be performed by computerized tomography using ir-RECIST criteria at 3 months from initiation of systemic treatment and on an 8 weekly basis thereafter until radiological proven disease progression or intolerance or patient choice.
The EORTC Quality of Life Questionnaire (QLQ-C30) questionnaire (to assess the quality of life) will be done at baseline after 3 months and then at discontinuation of study treatment.
Correlative translational study samples (blood) and tissue (used for histological confirmation and to document Programmed Death-Ligand 1 (PD-L1) expression) will be collected at baseline, and blood and serum samples monthly (after an informed optional consent and banked for retrospective immune-modulating and other biomarkers for future research and analysis).
101 studies on the registry are indexed under Neoplasms, Unknown Primary; 19 are open to participants now.
This study's enrollment of 35 is below the median of 52 across 63 interventional studies indexed under Neoplasms, Unknown Primary.
Browse Neoplasms, Unknown Primary studies →Imperial College London is the lead sponsor of 843 studies on the registry; 180 are open to participants now.
Of its 9 completed or terminated interventional studies of FDA-regulated products, 6 (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.
Cohort 1 - have had at least one prior line / regimen of chemotherapy appropriate for CUP (at least 2 cycles), have not had a RECIST response to chemotherapy, or are progressing after an initial response, or are treatment intolerant to first-line chemotherapy, due to unacceptable toxicity.
Cohort 2 - be chemo-naive for CUP*
*Previous chemotherapy for other cancers is allowed
Adequate organ and bone marrow function (all screening tests should be performed within 10 days of treatment initiation):
Serum creatinine ≤ 1.5 x (ULN) or * ≥ 60 mL/min for patients with creatinine levels > 1.5 x ULN
* Creatinine clearance should be calculated per institutional standard
Female subjects of childbearing potential must be willing to use an adequate method of as outlined in Section 6.9.2 - Contraception, for the course of the study through 120 days after the last dose of study medication.
Note: Abstinence is acceptable if this is the usual lifestyle and preferred contraception for the subject.
Note: Abstinence is acceptable if this is the usual lifestyle and preferred contraception for the subject.
Exclusion Criteria:
Has had prior chemotherapy, targeted small molecule therapy, or radiation therapy within 2 weeks prior to study Day 1 or who has not recovered (i.e., ≤ Grade 1 or at baseline) from adverse events due to a previously administered agent.
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.
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 line of therapy is one course of treatment, which may combine several drugs. First-line is the first course given; second-line follows when that stops working or is not tolerated.
“Two prior lines” means two courses that count separately under the study’s rules — not simply two drugs. Ask the study team if you are unsure how yours are counted.
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).
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.
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.
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.
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
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.
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.
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.
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.
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.
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.
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.
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.
Line of therapy
A line of therapy is one course of treatment, which may combine several drugs. First-line is the first course given; second-line follows when that stops working or is not tolerated.
“Two prior lines” means two courses that count separately under the study’s rules — not simply two drugs. Ask the study team if you are unsure how yours are counted.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
All trial treatments will be administered on an outpatient basis. Pembrolizumab 200 mg will be administered as a 30 minute IV infusion every 3 weeks. Sites should make every effort to target infusion timing to be as close to 30 minutes as possible. However, given the variability of infusion pumps from site to site, a window of -5 minutes and +10 minutes is permitted (i.e., infusion time is 30 minutes: -5 min/+10 min).
Drug: Pembrolizumab
Pembrolizumab has high affinity and potent receptor blocking activity for PD-1, based on preclinical in vitro data. Pembrolizumab has an acceptable preclinical and clinical safety profile and is in clinical development as an IV immunotherapy for advanced malignancies. The PD-1 pathway represents a major immune control switch, which may be engaged by tumour cells to overcome active T-cell immune surveillance. Pembrolizumab is a potent and highly selective humanized mAb of the Immunoglobulin (IgG4)/kappa isotype designed to directly block the interaction between PD-1 and its ligands, PD-L1 and PD-L2. This blockade enhances functional activity of the target lymphocytes to facilitate tumor regression and ultimately immune rejection.
Also known as: Keytruda
Overall Response Rate (ORR) by RECIST Criteria v1.1 in the Second-line & First-line Setting.
The Response Evaluation Criteria in Solid Tumours (RECIST) criteria v1.1. classifies response based on the assessment of target and non-target lesions on CT scans as: Complete Response (CR): requires all of: * disappearance of all target and non-target lesions * pathological lymph nodes must have reduced to \<10 mm in short axis * no new lesions Partial Response (PR): requires all of: * at least 30% decrease in sum of diameters (SOD) of target lesions compared to baseline sum diameters * non-progressive disease of non-target lesions * no new lesions Progressive Disease (PD): either one of: * any new lesions * at least 20% relative and 5 mm absolute increase of SOD of target lesions compared to smallest SOD ever recorded for the patient Stable Disease (SD): not meeting criteria for PD or PR.
Time frame: From the start of the study treatment until the end of treatment, an average of 6-8 months.
Incidence Proportion of Adverse Events up to 8 Weeks After the Last Dose of Pembrolizumab in the Second Line Setting
The number of patients with any recorded adverse events (AE) defined as any untoward or unfavorable medical occurrence in a participant, including any abnormal sign (for example, abnormal physical exam or laboratory finding), symptom, or disease, temporally associated with the participant's participation in the research, whether or not considered related to the participant's participation in the trial. The incidence proportion or cumulative incidence is the percentage (%) of patients developing new AEs out of the total number at risk followed during that time frame.
Time frame: 6-8 months, based on average length of treatment per patient
Incidence of Adverse Events up to 8 Weeks After the Last Dose of Pembrolizumab in Performance Status 2 (PS2) Patients in Any Setting
The number of patients whose Performance Status was equal to two at baseline, with any recorded adverse events (AE) defined as any untoward or unfavorable medical occurrence in a participant, including any abnormal sign (for example, abnormal physical exam or laboratory finding), symptom, or disease, temporally associated with the participant's participation in the research, whether or not considered related to the participant's participation in the trial. The incidence proportion or cumulative incidence is the percentage (%) of patients developing new AEs out of the total number at risk followed during that time frame.
Time frame: 6-8 months (based on average length of treatment per patient)
Identification of Potential Genomic Biomarkers Predictive of Immune Response to Pembrolizumab
This would be a retrospective analysis of blood samples collected for future research purposes only. Research bloods will be used to examine DNA and measure various blood biomarkers. These biomarkers may predict possible response to study treatment. As these samples are being taken before, during and after treatment, they will help us understand how the study treatments work. This will also enable us to learn whether or not the treatments have the desired effect, and to understand if these effects may be beneficial for the treatment of cancer of unknown primary (CUP). This information may also be used to develop and test other new treatments in the future. The panel of potential biomarkers against which the blood plasma will be tested has not been established yet. Information gained from this research component is not directly beneficial to patients taking part in this clinical trial.
Time frame: 12 months (post study completion)
| Milestone | Pembrolizumab |
|---|---|
| Started | 35 |
| Completed | 35 |
| Not completed | 0 |
The Response Evaluation Criteria in Solid Tumours (RECIST) criteria v1.1. classifies response based on the assessment of target and non-target lesions on CT scans as: Complete Response (CR): requires all of: * disappearance of all target and non-target lesions * pathological lymph nodes must have reduced to \<10 mm in short axis * no new lesions Partial Response (PR): requires all of: * at least 30% decrease in sum of diameters (SOD) of target lesions compared to baseline sum diameters * non-progressive disease of non-target lesions * no new lesions Progressive Disease (PD): either one of: * any new lesions * at least 20% relative and 5 mm absolute increase of SOD of target lesions compared to smallest SOD ever recorded for the patient Stable Disease (SD): not meeting criteria for PD or PR.
| Participants | Pembrolizumab |
|---|---|
| Complete Response (CR) | 0 |
| Partial Response (PR) | 4 |
| Stable Disease (SD) | 9 |
| Progressive Disease (PD) | 13 |
| Not Evaluable (NE) | 9 |
The number of patients with any recorded adverse events (AE) defined as any untoward or unfavorable medical occurrence in a participant, including any abnormal sign (for example, abnormal physical exam or laboratory finding), symptom, or disease, temporally associated with the participant's participation in the research, whether or not considered related to the participant's participation in the trial. The incidence proportion or cumulative incidence is the percentage (%) of patients developing new AEs out of the total number at risk followed during that time frame.
| Participants | Pembrolizumab |
|---|---|
| Incidence Proportion of Adverse Events up to 8 Weeks After the Last Dose of Pembrolizumab in the Second Line Setting | 34 |
The number of patients whose Performance Status was equal to two at baseline, with any recorded adverse events (AE) defined as any untoward or unfavorable medical occurrence in a participant, including any abnormal sign (for example, abnormal physical exam or laboratory finding), symptom, or disease, temporally associated with the participant's participation in the research, whether or not considered related to the participant's participation in the trial. The incidence proportion or cumulative incidence is the percentage (%) of patients developing new AEs out of the total number at risk followed during that time frame.
| Participants | Pembrolizumab |
|---|---|
| Incidence of Adverse Events up to 8 Weeks After the Last Dose of Pembrolizumab in Performance Status 2 (PS2) Patients in Any Setting | 5 |
This would be a retrospective analysis of blood samples collected for future research purposes only. Research bloods will be used to examine DNA and measure various blood biomarkers. These biomarkers may predict possible response to study treatment. As these samples are being taken before, during and after treatment, they will help us understand how the study treatments work. This will also enable us to learn whether or not the treatments have the desired effect, and to understand if these effects may be beneficial for the treatment of cancer of unknown primary (CUP). This information may also be used to develop and test other new treatments in the future. The panel of potential biomarkers against which the blood plasma will be tested has not been established yet. Information gained from this research component is not directly beneficial to patients taking part in this clinical trial.
Results for this outcome have not been posted.
Collected over From the start of the study treatment until the end of treatment, an average of 6-8 months.. Non-serious events are listed at a 5% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Pembrolizumab | 27/35 (77.1%) | 20/35 (57.1%) | 15/35 (42.9%) |
| Event | Pembrolizumab |
|---|---|
| Alanine aminotransferase increasedInvestigations | 2/35 |
| DiarrhoeaGastrointestinal disorders | 2/35 |
| Abdominal painGastrointestinal disorders | 2/35 |
| HyponatraemiaMetabolism and nutrition disorders | 1/35 |
| ConfusionPsychiatric disorders | 1/35 |
| Pericardial effusionCardiac disorders | 1/35 |
| Peripheral swellingCardiac disorders | 1/35 |
| HypoaesthesiaNervous system disorders | 1/35 |
| Haemoglobin decreasedInvestigations | 1/35 |
| Pleural effusionRespiratory, thoracic and mediastinal disorders | 1/35 |
| Event | Pembrolizumab |
|---|---|
| FatigueGeneral disorders | 14/35 |
| Abdominal painGastrointestinal disorders | 9/35 |
| ConstipationGastrointestinal disorders | 8/35 |
| VomitingGastrointestinal disorders | 8/35 |
| Decreased appetiteMetabolism and nutrition disorders | 6/35 |
| HypothyroidismEndocrine disorders | 6/35 |
| ArthralgiaMusculoskeletal and connective tissue disorders | 5/35 |
| NauseaGastrointestinal disorders | 5/35 |
| PyrexiaGeneral disorders | 5/35 |
| DyspnoeaRespiratory, thoracic and mediastinal disorders | 4/35 |
| Age, Continuous(years) | Pembrolizumab |
|---|---|
| Median | 58 (50 to 66) |
| Sex: Female, Male(Participants) | Pembrolizumab |
|---|---|
| Female | 21 |
| Male | 14 |
| Ethnicity (NIH/OMB)(Participants) | Pembrolizumab |
|---|---|
| Hispanic or Latino | 0 |
| Not Hispanic or Latino | 33 |
| Unknown or Not Reported | 2 |
| Region of Enrollment(participants) | Pembrolizumab |
|---|---|
| United Kingdom | 35 |
| Histology(Participants) | Pembrolizumab |
|---|---|
| Poorly differentiated adenocarcinoma or carcinoma | 11 |
| Well or Moderately Differentiated Adenocarcinoma | 9 |
| Undifferentiated Adenocarcinoma or Carcinoma | 8 |
| Squamous cell carcinoma | 7 |
| Eastern Cooperative Oncology Group (ECOG) Performance Status(Participants) | Pembrolizumab |
|---|---|
| 0 to 1 | 30 |
| 2 | 5 |
| EORTC QLQ-C30 Summary Score(units on a scale) | Pembrolizumab |
|---|---|
| Mean | 70 ± 18 |
PDFs hosted by the registry, ClinicalTrials.gov.
Plan to share: No
Ran from Feb 2019 to primary completion in Mar 2025, 73 months.
Results were first posted in May 2026, 1 year 1 month after primary completion.
How these figures are worked out, and which studies are left out of them.
This study is completed, as verified in Apr 2026. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Pembrolizumab