A Phase 2 interventional study of N-803 and ETBX-71 Vaccine in Recurrent Prostate Cancer and Prostate Cancer, sponsored by National Cancer Institute (NCI). Recruiting at 1 site in United States. Open to male participants aged 18 Years to 120 Years. Per ClinicalTrials.gov, last updated 2026-10-06.
Sponsored by National Cancer Institute (NCI) · Phase 2, Interventional, and Treatment
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Among 202 studies in Prostatic Neoplasms by National Cancer Institute (NCI) — 26 open to participants now, 43 under way, none of them phase 3. Prostatic Neoplasms · National Cancer Institute (NCI).
Among the 202 studies in Prostatic Neoplasms by National Cancer Institute (NCI), this one is the 49th largest by planned enrollment of the 166 interventional ones that give a count, is one of 6 that started in 2026, is one of 100 in phase 2, reaches primary completion later than 26 of the 37 other live ones, and was the 200th registered.
7,047 studies on the registry are indexed under Prostatic Neoplasms; 1,579 are open to participants now.
Browse Prostatic Neoplasms studies →26 of the 202 studies in Prostatic Neoplasms by National Cancer Institute (NCI) are open now, in 2 countries. Recruiting first, the newest first:
National Cancer Institute (NCI) · Sites in United States
Ages 18–120 · Men only
National Cancer Institute (NCI) · Sites in United States
Ages 18–120
National Cancer Institute (NCI) · Sites in United States
Ages 45–75 · Healthy volunteers
National Cancer Institute (NCI) · Sites in United States
Ages 18–120 · Men only
National Cancer Institute (NCI) · Sites in United States
Ages 18–120 · Men only
By country, each count listing its studies:
Of the 1,228 Prostatic Neoplasms studies recruiting now, 927 (75%) set no upper age limit and 76 (6%) stop at 75 or younger; 67 take children under 18; 82 take healthy volunteers.
This study: 18 Years to 120 Years · male · no healthy volunteers.
The full table on the hub →This tab as a report to print or save as PDF → With an account.
202 studies; the count open now beside each. This study's row is marked.
A study in two phases is counted once above. Listed by phase, each with its combined phases: Phase 1 61 · Phase 2 116 · Phase 3 5
First in 1988; this study’s year is marked. 6 started in 2026.
By drug class, each counting the studies that test any of its medicines:
This study's planned enrollment of 65 is close to the median of 60 across 5,349 interventional studies indexed under Prostatic Neoplasms.
Median enrollment 41 across the 166 interventional studies, 1,016 across the 30 observational. Of the 154 that completed or were terminated, 84 (55%) have results posted.
This tab as a report to print or save as PDF → With an account.
National Cancer Institute (NCI) is the lead sponsor of 3,556 studies on the registry; 336 are open to participants now.
Of its 412 completed or terminated interventional studies of FDA-regulated products, 374 (91%) have results posted.
11 of the studies in Prostatic Neoplasms by National Cancer Institute (NCI) that are under way reach primary completion within a year, 0 of them phase 3. Phase 3 first, then by date:
| Study | Primary completion |
|---|---|
| NCT05588128National Cancer Institute (NCI)Prospective Monitoring of Subjects With Biochemically Recurrent Prostate Cancer Using 18FDCFPyL | 2026-12-31 |
| NCT04633252National Cancer Institute (NCI)A Phase I/II Study of PDS01ADC With Docetaxel and Abiraterone in Adults With Metastatic Castration Sensitive and PDS01ADC With Docetaxel in Castration Resistant Prostate Cancer | 2026-12-31 |
| NCT05828082National Cancer Institute (NCI)Testing the Effect of M1774 on Hard-to-Treat Refractory SPOP-mutant Prostate Cancer | 2027-01-01 |
| NCT01834001National Cancer Institute (NCI)Imaging Studies to Check the Local Response of Prostate Cancer to Radiation Therapy | 2027-02-25 |
| NCT03866382National Cancer Institute (NCI)Testing the Effectiveness of Two Immunotherapy Drugs (Nivolumab and Ipilimumab) With One Anti-cancer Targeted Drug (Cabozantinib) for Rare Genitourinary Tumors | 2027-02-28 |
Add all 11 to your calendar (.ics) → With an account.
Among the 202 studies in Prostatic Neoplasms by National Cancer Institute (NCI), from their registry updates:
This tab as a report to print or save as PDF → With an account.
Background:
Biochemically recurrent prostate cancer (BCR) occurs when prostate-specific antigen (PSA) levels in the blood rise after surgery or radiation. BCR affects 30,000 to 50,000 men each year. Researchers want to know if a drug (N-803) alone or combined with a vaccine (ETBX-071) can reduce PSA in BCR prostate cancer after radiation.
Objective:
To test a study drug alone and combined with a vaccine in people with BCR prostate cancer who have been treated with targeted radiation to areas of recurrent prostate cancer in the past.
Eligibility:
People aged 18 years and older with BCR prostate cancer who have previously undergone treatment with stereotactic body radiation therapy (SBRT).
Design:
Participants will be screened. They will have a physical exam with blood tests. They will have tests of their heart and kidney function. They will have 3 different imaging scans of their tumors.
N-803 is injected under the skin of the abdomen. ETBX-071 is injected under the skin of thigh.
Participants will be divided into 2 groups: 1 group will get N-803 alone; 1 group will get both N-803 and ETBX-071.
The drug or drugs will be given on the first day of 21-day treatment cycles. Participants will have 8 treatment cycles.
Participants will have a follow-up visit 3 weeks after their last dose of the study drugs. Blood tests and all 3 imaging scans will be repeated.
Follow-up visits will continue every 4 to 8 weeks for 5 years. These visits will include a positron emission tomography (PET) scan every 6 months.
Background:
Objectives:
-To estimate efficacy of N-803 alone or with ETBX-071 vaccine, each administered for 6 months, in participants with biochemically recurrent prostate cancer following PSA progression after SBRT
Eligibility:
Design:
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.
Hematological parameters:
EXCLUSION CRITERIA:
status due to:
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 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.
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.
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.
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.
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.
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 that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
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).
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 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.
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.
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.
Stem cell (bone marrow) transplants. Allogeneic uses cells from a donor; autologous uses your own cells, collected earlier and given back.
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 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.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
Allogeneic and autologous transplant
Stem cell (bone marrow) transplants. Allogeneic uses cells from a donor; autologous uses your own cells, collected earlier and given back.
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.
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.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
NYHA class (heart failure)
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
N803
Drug: N-803 · Radiation: 18F-DCFPyL
N803+ETBX-071 vaccine
Drug: N-803 · Drug: ETBX-71 Vaccine · Radiation: 18F-DCFPyL
15 mg/kg subcutaneous on Day 1 of every 3-week cycle for up to 8 cycles
The dose to be injected is 5(SqrRoot) 10\^11 viral particles (VP) per 1 mL. Injected subcutaneously on Day 1 of every 3-week cycle for a total of up to 8 cycles
Single IV dose of 18F-DCFPyL by bolus injection. The target administered activity will be 6.5 mCi with a lower limit of 6 mCi
Efficacy of N-803 alone or with ETBX-071 vaccine
PSA30 response- defined as a \>= 30% reduction in PSA from PSA at C1D1 of immunotherapy (comparing C1D1 PSA to timepoints during and after immunotherapy). The fractions with PSA30 response will be reported along with a 95% confidence interval, separately for the two randomized treatment groups.
Time frame: D1 of each cycle of immunotherapy, at the end of treatment and every 4-8 weeks during follow-up until up to 5 years
Duration of PSA50 response
Duration of PSA response will be evaluated using the Kaplan-Meier method unless all participants are identified as having an end to their response (no censoring). The median duration of PSA response will be reported, starting at the date the PSA30 response was identified, along with a 95% confidence interval for the median, separately for the two randomized treatment groups.
Time frame: D1 of each cycle of immunotherapy, at the end of treatment and every 4-8 weeks during follow-up until up to 5 years
Time to PSA progression
Time to PSA progression after immunotherapy will be evaluated using the Kaplan-Meier method unless all participants are identified as having an end to their response (no censoring). The median time to PSA progression will be reported, starting at the date Cycle 1 began, along with a 95% confidence interval for the median.
Time frame: D1 of each cycle of immunotherapy, at the end of treatment and every 4-8 weeks during follow-up until up to 5 years
PSA doubling timing
PSA doubling time at randomization, compared to PSA doubling time at the end of treatment (EOT) visit.
Time frame: D1 of each cycle of immunotherapy, at the end of treatment and every 4-8 weeks during follow-up until up to 5 years
Proportion of participants with 30% PSA decline receiving immunotherapy treatment after SBRT
The median changes in PSA doubling time (in months) will be determined separately for both treatment groups with paired differences compared within participants using a Wilcoxon signed rank test.
Time frame: D1 of each cycle of immunotherapy, at the end of treatment and every 4-8 weeks during follow-up until up to 5 years
Safety
The number, grades, and types of adverse events will be reported separately for participants assigned to each treatment group using descriptive statistics.
Time frame: C1D1 of each cycle during immunotherapy and at the end of treatment
Changes in PSMA PET scans
These will be summarized descriptively.
Time frame: Prior to treatment, at end of treatment and in follow-up every 6 months
Plan to share: Yes — This study will comply with the NIH Data Management and Sharing (DMS) Policy, which applies to all new and ongoing NIH-funded research in the IRP, as of January 25, 2023, that is associated with a ZIA, with a clinical protocol that undergoes scientific review and/or will involve genomic data sharing.
Supporting information: Study protocol, Statistical analysis plan, Informed consent form
Time frame: Data will be made available as soon as possible or at the time of associated publication. Data not published in a manuscript will be shared via public source once the data set completes QC.@@@@@@
Access criteria: Clinical data will be made available upon request and with the permission of the study PI. Genomic data are made available via dbGAP through requests to the data custodians.@@@@@@
Started Oct 2026 (actual). Primary completion is estimated for Jan 2029, 27 months after the start.
Of 610 non-industry phase 2 interventional studies under Prostatic Neoplasms, half reached primary completion within 57 months of starting (the median), counting those still running; a quarter within 39 and three quarters within 86. This study's planned 27 months is below that.
Counting every sponsor, half of 724 studies reached it within 53 months; a quarter within 34 and three quarters within 81.
Start moved 8 times since we started tracking on Sep 25, 2026: Sep 2026 → Oct 2026, last on Oct 6, 2026.
Earlier changes are on the record history on ClinicalTrials.gov ↗
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
Contact study teamGet an email when the registry record changes — status, dates, results — or when someone posts here.
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Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Studies of the drug tested here: Nogapendekin alfa inbakicept
National Cancer Institute (NCI) →