Skip to content

Prostvac in Patients With Biochemically Recurrent Prostate Cancer

Prostvac in Patients With Biochemically Recurrent Prostate Cancer

Status
Completed
Phases
Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT02649439
Enrollment
97
Registered
2016-01-07
Start date
2015-12-22
Completion date
2022-10-01
Last updated
2022-11-14

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Prostate Cancer

Keywords

Vaccine, PSA, Surveillance, Immunotherapy

Brief summary

Background: Some people who have been treated for prostate cancer still have high prostate-specific antigen (PSA) levels. This may indicate cancer. These people have non-metastatic castration sensitive prostate cancer (nmCSPC) or biochemical recurrent prostate cancer. Researchers think the immune system can be taught to fight and kill cancer cells. They think an immunotherapy vaccine called prostvac could help reduce PSA levels in people with this type of prostate cancer. Objective: To test if prostvac can decrease tumor growth rate as measured by PSA compared to getting surveillance alone. Eligibility: Men ages 18 or older who have nmCSPC or biochemical recurrent prostate cancer Design: Participants will be screened with: Medical history Physical exam Blood and urine tests Bone scan Computed tomography (CT) scan, or magnetic resonance imaging (MRI) and positron emission tomography (PET) scan: They lie in a machine that takes pictures of the body. Electrocardiogram: Soft electrodes are stuck to the skin to record heart signals. Participants will be part of 1 of 2 arms: Arm A will get prostvac for 6 months. Arm B will have surveillance for 6 months followed by prostvac for 6 months. During the prostvac period, participants will get prostvac as a shot under the skin on weeks 1, 3, and 5, and then monthly for a total of 5 months. Participants will have follow-up visits at least every month until they recover from prostvac side effects or their cancer worsens. Visits may include repeats of screening tests. Participants will be followed for up to 15 years. They will have a physical exam every year for the first 5 years. They will have phone calls once a year.

Detailed description

BACKGROUND * Androgen deprivation therapy (ADT) and surveillance are treatment options for prostate cancer patients with biochemical progression after localized therapy (biochemically recurrent prostate cancer). The primary goal in these patients is to prevent morbidity from their cancer and to do so with limited toxicity. * Prostvac (Prostvac; developed by the National Cancer Institute \[NCI\] and licensed to BN Immunotherapeutics, Mountain View, CA) is a novel candidate prostate cancer immunotherapy for the treatment of prostate cancer. It is a viral vector based therapeutic cancer vaccine that is administered via subcutaneous injections. In a randomized controlled Phase 2 trial, Prostvac therapy was associated with a prolongation of survival in men with metastatic castrate-resistant prostate cancer. A phase III trial recently completed accrual of patients in this same population. * There is also rationale to use therapeutic cancer vaccines such as Prostvac in earlier stage prostate cancer patients to maximize the potential therapeutic effect of immune stimulating therapy. * Analysis of previous trials using therapeutic cancer vaccines alone suggests that such therapies may alter tumor growth rate. OBJECTIVE Primary Objective: -Determine if the therapeutic cancer vaccine prostvac can decrease tumor growth rate as measured by prostate-specific antigen (PSA) rise after 6 months compared to a group getting surveillance alone. KEY ELIGIBILITY CRITERIA * Histologically confirmed adenocarcinoma of the prostate * Patients with negative computed tomography (CT) Scan and Tc-99m Bone Scan * Patients with a PSA over 0.8 ng/ml for patients following radical prostatectomy or for patients following definitive radiation therapy: a rise in PSA of greater than or equal to 2 ng/mL above the nadir * Patients with a PSA doubling time of 5-15 months * No history of active autoimmune disease or history of organ compromising autoimmune disease * Eastern Cooperative Oncology Group (ECOG) 0 -1 DESIGN * Randomized study * Accrual goal is 36 evaluable patients per arm; randomized 1:1 to: * Arm A: Prostvac for 6 months with an additional optional year of maintenance for eligible patients OR * Arm B: Surveillance for 6 months, then Prostvac for 6 months with an additional year of maintenance for eligible patients

Interventions

BIOLOGICALPROSTVAC -V

Recombinant Vaccinia Virus Vector Vaccine of the Genus Orthopoxvirus

BIOLOGICALPROSTVAC-F

Recombinant Fowlpox Virus Vector Vaccine of the Genus Avipoxvirus

Sponsors

National Cancer Institute (NCI)
Lead SponsorNIH

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
MALE
Age
18 Years to 100 Years
Healthy volunteers
No

Inclusion criteria

* INCLUSION CRITERIA: * Histopathological documentation of prostate cancer confirmed in either the Laboratory of Pathology at the National Institutes of Health (NIH) Clinical Center, Walter Reed National Military Medical Center, Memorial Sloan Kettering Cancer Center (MSKCC), Dana-Farber Cancer Institute (DFCI) or Beth Israel Deaconess Medical Center (BIDMC) prior to enrollment. If no pathologic specimen is available, patients may enroll with a pathologists report showing a histologic diagnosis of prostate cancer and a clinical course consistent with the disease. * Biochemical progression after definitive radiation or surgery defined as follows: * For patients following definitive therapy: a rise in prostate-specific antigen (PSA) of greater than or equal to 2ng/mL above the nadir (per Radiation Therapy Oncology Group (RTOG)-American Society for Therapeutic Radiology and Oncology (ASTRO) consensus criteria). * For patients following radical prostatectomy: rising PSA after surgical procedure. (Patients must have a PSA greater than or equal to 0.8 ng/ml) * Eastern Cooperative Oncology Group (ECOG) performance status of 0 1 (Karnofsky greater than or equal to 80%). * Patients must have a PSA doubling time of 5-15 months. * Patients must have a rising PSA as confirmed by 3 values done at least 1 week apart and over no less than 1 month. * Recovery from acute toxicity related to prior therapy, including surgery and radiation, or no toxicity greater than or equal to grade 2. * Negative computed tomography (CT) scan/magnetic resonance imaging (MRI) and bone scan for metastatic prostate cancer. * Hematological eligibility parameters (within 16 days before starting therapy) * Granulocyte count greater than or equal to 1000/mm\^3 * Platelet count greater than or equal to 100 000/mm\^3 * Hemoglobin (Hgb) greater than or equal to 10g/dL * Biochemical eligibility parameters (within 16 days before starting therapy): --Hepatic function: bilirubin less than or equal to 1.5mg/dL (OR in patients with Gilbert's syndrome normal. * No other active malignancies within the past 36 months (with the exception of nonmelanoma skin cancers or carcinoma in situ of the bladder) or life-threatening illnesses, in the opinion of the investigator * Willing to travel to the National Institutes of Health (NIH), MSKCC, DFCI, BIDMC for follow-up visits. * 18 years of age or older. * Able to understand and sign informed consent. * Baseline testosterone greater than or equal to 100 ng/dl * PSA less than or equal to 30 ng/mL. * The effects PROSTVAC on the developing human fetus are unknown. For this reason, men must agree to use adequate contraception (hormonal or barrier method of birth control; abstinence) prior to study entry, for the duration of study therapy and at least one month post therapy. Should a woman become pregnant or suspect she is pregnant while her partner is participating in this study, she should inform her treating physician immediately.

Exclusion criteria

* Immunocompromised status due to: * Human immunodeficiency virus (HIV) positivity. * Active autoimmune diseases such as Addison's disease, Hashimoto's thyroiditis, systemic lupus erythematosus, Sjogren syndrome, scleroderma, myasthenia gravis, Goodpasture syndrome or active Grave's disease. Patients with a history of autoimmunity that has not required systemic immunosuppressive therapy or does not threaten vital organ function including central nervous system (CNS), heart, lungs, kidneys, skin, and gastrointestinal (GI) tract will be allowed. * Other immunodeficiency diseases * Splenectomy * Chronic administration (defined as daily or every other day for continued use \> 14 days) of corticosteroids deemed systemic by investigator within 28 days before the first planned dose of PROSTVAC. Use of inhaled steroids, nasal sprays, intra-articular injections and topical creams for small body areas is allowed. * Serious intercurrent medical illness that, in the judgment of the investigator, would interfere with patient s ability to carry out the treatment program. * Other medications used for urinary symptoms including 5-alpha reductase inhibitors (finasteride and dutasteride) and alternative medications known to alter PSA (eg phytoestrogens and saw palmetto) * History of prior chemotherapy * History of prior immunotherapy within the last 3 years * Major surgery within 4 weeks prior to enrollment (Day 1 visit). * History of allergic reactions attributed to compounds of similar chemical or biologic composition to poxviral vaccines (e.g., vaccinia vaccine) * Known allergy to eggs, egg products, aminoglycoside antibiotics (for example, gentamicin or tobramycin). * History of atopic dermatitis or active skin condition (acute, chronic, exfoliative) that disrupts the epidermis * Previous serious adverse reactions to smallpox vaccination * Unable to avoid close contact or household contact with the following high-risk individuals for three weeks after the Day 1 vaccination: Day 1 vaccination: (a) children less than or equal to 3 years of age, (b) pregnant or nursing women, (c) individuals with current or extensive eczema or other eczemoid skin disorders, or (d) immunocompromised individuals, such as those with HIV. * Receipt of an investigational agent within 28 days (or 56 days for an antibody-based therapy) before the first planned dose of study drugs. * Patients who test positive for hepatitis B virus (HBV) or hepatitis C virus (HCV) * Uncontrolled hypertension (systolic blood pressure (SBP)\>170/ DBP\>105) * Recruitment Strategies This study will be listed on available websites (www.clinicaltrials.gov, https://ccr.cancer.gov/clinical-trials-search-start) and participants will be recruited from the current patient population at NIH.

Design outcomes

Primary

MeasureTime frameDescription
Tumor Growth Rate as Measured by Prostate-specific Antigen (PSA) Rise After 6 Months When PROSTVAC is Initiated Compared to a Group on Surveillance for 6 Months6 monthsTumor growth rate was measured using the equation PSA (log growth rate) +/- SE (standard error).

Secondary

MeasureTime frameDescription
Effects of Vaccine on Prostate-specific Antigen (PSA) Growth Rate When PROSTVAC is Initiated After 6 Months on SurveillanceAfter the participants in the Arm/Group B/ Delayed PROSTVAC Treatment received treatment for 6 months after their 6 month surveillance (e.g., 12 months total).Tumor growth rate was measured using the equation PSA (log growth rate) +/- SE (standard error).
Number of Participants With Prostate-specific Antigen (PSA) Specific T-Cells at Baseline and 6 MonthsBaseline and 6 monthsNormal PSA is 0 nanograms per milliliter (ng/mL). Above 0 ng/mL is considered an increase in tumor growth.

Other

MeasureTime frameDescription
Number of Participants With Serious and Non-serious Adverse Events Assessed by the Common Terminology Criteria for Adverse Events (CTCAE v4.0)Date treatment consent signed to date off study, approximately 55 months and 13 days for Arm/Group A, and 57 months and 22 days for Arm/Group B.Here is the number of participants with serious and non-serious adverse events assessed by the Common Terminology Criteria for Adverse Events (CTCAE v4.0). A non-serious adverse event is any untoward medical occurrence. A serious adverse event is an adverse event or suspected adverse reaction that results in death, a life-threatening adverse drug experience, hospitalization, disruption of the ability to conduct normal life functions, congenital anomaly/birth defect or important medical events that jeopardize the patient or subject and may require medical or surgical intervention to prevent one of the previous outcomes mentioned.
Peripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC), and naïve CD4 and CD8 T Cells After PROSTVACBaseline (Day 1) and one month (Day 29) after vaccine or surveillance (in the Delayed PROSTVAC group)Blood samples collected were analyzed by multicolor flow cytometry in PBMCs for cluster of differentiation 4 (CD4), cluster of differentiation 8 (CD8), Natural Killer (NK), myeloid-derived suppressor cell (MDSC), Tregs, and naïve CD4 and naïve CD8 T cells. P values were calculated using the Wilcoxon signed rank test.
Median Late Change in Peripheral Blood Mononuclear Cells (PBMCs) in Refined Subsets Monocyte Nonclassical, Monocyte Nonclassical Programmed Death Ligand 1 (PD-L1+), and Monocyte PD-1+ After PROSTVACDay 29 (Post vaccination) vs Pre (Baseline)Blood samples collected were analyzed by multicolor flow cytometry in PBMCs for refined subsets of Monocytes. Changes in levels of PBMC subsets was a descriptive result with median percent change and interquartile range reported. P values were calculated using the Mann Whitney Test.
Median Late Change in Peripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC) After PROSTVACDay 29 (Post vaccination) vs Pre (Baseline)Blood samples collected were analyzed by multicolor flow cytometry in PBMCs for cluster of differentiation 4 (CD4), cluster of differentiation 8 (CD8), Natural Killer (NK), myeloid-derived suppressor cell (MDSC) and Tregs. P values were calculated using the Mann Whitney Test.

Countries

United States

Participant flow

Recruitment details

A total of 97 participants were enrolled and 17/97 were screen failures who were enrolled and not treated. They are not included in the table because potential participants who are screened for the purpose of determining eligibility, but do not participate, are not considered enrolled unless otherwise specified by the protocol, and that is not otherwise specified in the protocol.

Participants by arm

ArmCount
A/PROSTVAC Treatment
PROSTVAC treatment for 6 months with an additional optional year of maintenance for eligible patients PROSTVAC -V: Recombinant Vaccinia Virus Vector Vaccine of the Genus Orthopoxvirus PROSTVAC-F: Recombinant Fowlpox Virus Vector Vaccine of the Genus Avipoxvirus
40
B/ Delayed PROSTVAC Treatment
Surveillance for 6 months followed by PROSTVAC treatment for 6 months with an additional year of maintenance for eligible patients PROSTVAC -V: Recombinant Vaccinia Virus Vector Vaccine of the Genus Orthopoxvirus PROSTVAC-F: Recombinant Fowlpox Virus Vector Vaccine of the Genus Avipoxvirus
40
Total80

Withdrawals & dropouts

PeriodReasonFG000FG001
Overall StudyCompleted treatment phase but refused the protocol specified follow up10
Overall StudyDisease progression on study1213
Overall StudyNo treatment, per protocol10
Overall StudyPatient decision10
Overall StudyPatient going out of country10
Overall StudyPhysician Decision10
Overall StudyPSA DT makes ineligible01
Overall StudyRefused further follow up27
Overall StudyRefused further treatment10
Overall StudyRising PSA01
Overall StudyRising PSA No Mets01
Overall StudySigned follow up protocol01
Overall StudySwitched to alternative treatment64
Overall StudyTo start finasteride10

Baseline characteristics

CharacteristicA/PROSTVAC TreatmentTotalB/ Delayed PROSTVAC Treatment
Age, Categorical
<=18 years
0 Participants0 Participants0 Participants
Age, Categorical
>=65 years
28 Participants50 Participants22 Participants
Age, Categorical
Between 18 and 65 years
12 Participants30 Participants18 Participants
Age, Continuous67.06 years
STANDARD_DEVIATION 6.48
67.04 years
STANDARD_DEVIATION 6.52
67.02 years
STANDARD_DEVIATION 6.56
Ethnicity (NIH/OMB)
Hispanic or Latino
1 Participants3 Participants2 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
32 Participants63 Participants31 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
7 Participants14 Participants7 Participants
Median Prostate Specific Antigen (PSA)2.98 ng/ml2.9 ng/ml2.82 ng/ml
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Asian
1 Participants4 Participants3 Participants
Race (NIH/OMB)
Black or African American
4 Participants8 Participants4 Participants
Race (NIH/OMB)
More than one race
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Unknown or Not Reported
2 Participants3 Participants1 Participants
Race (NIH/OMB)
White
33 Participants65 Participants32 Participants
Region of Enrollment
United States
40 participants80 participants40 participants
Sex: Female, Male
Female
0 Participants0 Participants0 Participants
Sex: Female, Male
Male
40 Participants80 Participants40 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
0 / 400 / 40
other
Total, other adverse events
40 / 4039 / 40
serious
Total, serious adverse events
3 / 406 / 40

Outcome results

Primary

Tumor Growth Rate as Measured by Prostate-specific Antigen (PSA) Rise After 6 Months When PROSTVAC is Initiated Compared to a Group on Surveillance for 6 Months

Tumor growth rate was measured using the equation PSA (log growth rate) +/- SE (standard error).

Time frame: 6 months

ArmMeasureValue (NUMBER)
A/PROSTVAC TreatmentTumor Growth Rate as Measured by Prostate-specific Antigen (PSA) Rise After 6 Months When PROSTVAC is Initiated Compared to a Group on Surveillance for 6 Months-2.528 Unitless
B/ Delayed PROSTVAC TreatmentTumor Growth Rate as Measured by Prostate-specific Antigen (PSA) Rise After 6 Months When PROSTVAC is Initiated Compared to a Group on Surveillance for 6 Months-2.449 Unitless
p-value: 0.4852Wilcoxon signed rank test
Secondary

Effects of Vaccine on Prostate-specific Antigen (PSA) Growth Rate When PROSTVAC is Initiated After 6 Months on Surveillance

Tumor growth rate was measured using the equation PSA (log growth rate) +/- SE (standard error).

Time frame: After the participants in the Arm/Group B/ Delayed PROSTVAC Treatment received treatment for 6 months after their 6 month surveillance (e.g., 12 months total).

Population: 33/40 were evaluable in the first group.

ArmMeasureValue (NUMBER)
A/PROSTVAC TreatmentEffects of Vaccine on Prostate-specific Antigen (PSA) Growth Rate When PROSTVAC is Initiated After 6 Months on Surveillance-2.513 Unitless
B/ Delayed PROSTVAC TreatmentEffects of Vaccine on Prostate-specific Antigen (PSA) Growth Rate When PROSTVAC is Initiated After 6 Months on Surveillance-2.449 Unitless
p-value: 0.3269Wilcoxon signed rank test
Secondary

Number of Participants With Prostate-specific Antigen (PSA) Specific T-Cells at Baseline and 6 Months

Normal PSA is 0 nanograms per milliliter (ng/mL). Above 0 ng/mL is considered an increase in tumor growth.

Time frame: Baseline and 6 months

Population: 35/40 and 32/40 participants are reported because these are the numbers of participants with sufficient samples for analysis.

ArmMeasureGroupValue (COUNT_OF_PARTICIPANTS)
A/PROSTVAC TreatmentNumber of Participants With Prostate-specific Antigen (PSA) Specific T-Cells at Baseline and 6 MonthsBaseline22 Participants
A/PROSTVAC TreatmentNumber of Participants With Prostate-specific Antigen (PSA) Specific T-Cells at Baseline and 6 Months6 Months14 Participants
B/ Delayed PROSTVAC TreatmentNumber of Participants With Prostate-specific Antigen (PSA) Specific T-Cells at Baseline and 6 MonthsBaseline20 Participants
B/ Delayed PROSTVAC TreatmentNumber of Participants With Prostate-specific Antigen (PSA) Specific T-Cells at Baseline and 6 Months6 Months11 Participants
Other Pre-specified

Median Late Change in Peripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC) After PROSTVAC

Blood samples collected were analyzed by multicolor flow cytometry in PBMCs for cluster of differentiation 4 (CD4), cluster of differentiation 8 (CD8), Natural Killer (NK), myeloid-derived suppressor cell (MDSC) and Tregs. P values were calculated using the Mann Whitney Test.

Time frame: Day 29 (Post vaccination) vs Pre (Baseline)

Population: 7/40 and 29/40 participants were evaluable in the first and second group, respectively, based on availability of peripheral blood mononuclear cells (PBMCs) before and after vaccination.

ArmMeasureGroupValue (MEDIAN)
A/PROSTVAC TreatmentMedian Late Change in Peripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC) After PROSTVACClassic Subset CD81.2 Percent change
A/PROSTVAC TreatmentMedian Late Change in Peripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC) After PROSTVACClassic Subset NK26.2 Percent change
A/PROSTVAC TreatmentMedian Late Change in Peripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC) After PROSTVACClassic Subset Treg44.7 Percent change
A/PROSTVAC TreatmentMedian Late Change in Peripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC) After PROSTVACClassic Subset MDSC39.5 Percent change
A/PROSTVAC TreatmentMedian Late Change in Peripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC) After PROSTVACClassic Subset CD4-7.1 Percent change
B/ Delayed PROSTVAC TreatmentMedian Late Change in Peripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC) After PROSTVACClassic Subset MDSC20.9 Percent change
B/ Delayed PROSTVAC TreatmentMedian Late Change in Peripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC) After PROSTVACClassic Subset CD4-3.3 Percent change
B/ Delayed PROSTVAC TreatmentMedian Late Change in Peripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC) After PROSTVACClassic Subset CD82.8 Percent change
B/ Delayed PROSTVAC TreatmentMedian Late Change in Peripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC) After PROSTVACClassic Subset Treg0.7 Percent change
B/ Delayed PROSTVAC TreatmentMedian Late Change in Peripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC) After PROSTVACClassic Subset NK24.1 Percent change
p-value: 0.7317Mann Whitney Test
p-value: 0.7545Mann Whitney Test
p-value: 0.531Mann Whitney Test
p-value: 0.8451Mann Whitney Test
p-value: 0.9377Mann Whitney Test
Other Pre-specified

Median Late Change in Peripheral Blood Mononuclear Cells (PBMCs) in Refined Subsets Monocyte Nonclassical, Monocyte Nonclassical Programmed Death Ligand 1 (PD-L1+), and Monocyte PD-1+ After PROSTVAC

Blood samples collected were analyzed by multicolor flow cytometry in PBMCs for refined subsets of Monocytes. Changes in levels of PBMC subsets was a descriptive result with median percent change and interquartile range reported. P values were calculated using the Mann Whitney Test.

Time frame: Day 29 (Post vaccination) vs Pre (Baseline)

Population: 7/40 and 29/40 participants were evaluable in the first and second group, respectively, based on availability of peripheral blood mononuclear cells (PBMCs) before and after vaccination.

ArmMeasureGroupValue (MEDIAN)
A/PROSTVAC TreatmentMedian Late Change in Peripheral Blood Mononuclear Cells (PBMCs) in Refined Subsets Monocyte Nonclassical, Monocyte Nonclassical Programmed Death Ligand 1 (PD-L1+), and Monocyte PD-1+ After PROSTVACMonocyte Nonclassical Refined Subset-29.8 Percent change
A/PROSTVAC TreatmentMedian Late Change in Peripheral Blood Mononuclear Cells (PBMCs) in Refined Subsets Monocyte Nonclassical, Monocyte Nonclassical Programmed Death Ligand 1 (PD-L1+), and Monocyte PD-1+ After PROSTVACMonocyte Nonclassical PD-L1+ Refined Subset-57.5 Percent change
A/PROSTVAC TreatmentMedian Late Change in Peripheral Blood Mononuclear Cells (PBMCs) in Refined Subsets Monocyte Nonclassical, Monocyte Nonclassical Programmed Death Ligand 1 (PD-L1+), and Monocyte PD-1+ After PROSTVACMonocyte PD-1+ Refined Subset-55.7 Percent change
B/ Delayed PROSTVAC TreatmentMedian Late Change in Peripheral Blood Mononuclear Cells (PBMCs) in Refined Subsets Monocyte Nonclassical, Monocyte Nonclassical Programmed Death Ligand 1 (PD-L1+), and Monocyte PD-1+ After PROSTVACMonocyte Nonclassical Refined Subset9.3 Percent change
B/ Delayed PROSTVAC TreatmentMedian Late Change in Peripheral Blood Mononuclear Cells (PBMCs) in Refined Subsets Monocyte Nonclassical, Monocyte Nonclassical Programmed Death Ligand 1 (PD-L1+), and Monocyte PD-1+ After PROSTVACMonocyte Nonclassical PD-L1+ Refined Subset17.3 Percent change
B/ Delayed PROSTVAC TreatmentMedian Late Change in Peripheral Blood Mononuclear Cells (PBMCs) in Refined Subsets Monocyte Nonclassical, Monocyte Nonclassical Programmed Death Ligand 1 (PD-L1+), and Monocyte PD-1+ After PROSTVACMonocyte PD-1+ Refined Subset-17.2 Percent change
p-value: 0.0255Mann Whitney Test
p-value: 0.0021Mann Whitney Test
p-value: 0.0486Mann Whitney Test
Other Pre-specified

Number of Participants With Serious and Non-serious Adverse Events Assessed by the Common Terminology Criteria for Adverse Events (CTCAE v4.0)

Here is the number of participants with serious and non-serious adverse events assessed by the Common Terminology Criteria for Adverse Events (CTCAE v4.0). A non-serious adverse event is any untoward medical occurrence. A serious adverse event is an adverse event or suspected adverse reaction that results in death, a life-threatening adverse drug experience, hospitalization, disruption of the ability to conduct normal life functions, congenital anomaly/birth defect or important medical events that jeopardize the patient or subject and may require medical or surgical intervention to prevent one of the previous outcomes mentioned.

Time frame: Date treatment consent signed to date off study, approximately 55 months and 13 days for Arm/Group A, and 57 months and 22 days for Arm/Group B.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
A/PROSTVAC TreatmentNumber of Participants With Serious and Non-serious Adverse Events Assessed by the Common Terminology Criteria for Adverse Events (CTCAE v4.0)40 Participants
B/ Delayed PROSTVAC TreatmentNumber of Participants With Serious and Non-serious Adverse Events Assessed by the Common Terminology Criteria for Adverse Events (CTCAE v4.0)39 Participants
Other Pre-specified

Peripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC), and naïve CD4 and CD8 T Cells After PROSTVAC

Blood samples collected were analyzed by multicolor flow cytometry in PBMCs for cluster of differentiation 4 (CD4), cluster of differentiation 8 (CD8), Natural Killer (NK), myeloid-derived suppressor cell (MDSC), Tregs, and naïve CD4 and naïve CD8 T cells. P values were calculated using the Wilcoxon signed rank test.

Time frame: Baseline (Day 1) and one month (Day 29) after vaccine or surveillance (in the Delayed PROSTVAC group)

Population: 36 and 12participants were evaluable in the first and second group, respectively, based on availability of peripheral blood mononuclear cells (PBMCs) before and after vaccination or surveillance (in the Delayed PROSTVAC group).

ArmMeasureGroupValue (MEDIAN)
A/PROSTVAC TreatmentPeripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC), and naïve CD4 and CD8 T Cells After PROSTVACCD429.83 Percentage of PBMC
A/PROSTVAC TreatmentPeripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC), and naïve CD4 and CD8 T Cells After PROSTVACNaive CD47.23 Percentage of PBMC
A/PROSTVAC TreatmentPeripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC), and naïve CD4 and CD8 T Cells After PROSTVACMDSC4.60 Percentage of PBMC
A/PROSTVAC TreatmentPeripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC), and naïve CD4 and CD8 T Cells After PROSTVACCD88.87 Percentage of PBMC
A/PROSTVAC TreatmentPeripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC), and naïve CD4 and CD8 T Cells After PROSTVACNaïve CD81.51 Percentage of PBMC
A/PROSTVAC TreatmentPeripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC), and naïve CD4 and CD8 T Cells After PROSTVACTreg0.58 Percentage of PBMC
A/PROSTVAC TreatmentPeripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC), and naïve CD4 and CD8 T Cells After PROSTVACNK8.04 Percentage of PBMC
B/ Delayed PROSTVAC TreatmentPeripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC), and naïve CD4 and CD8 T Cells After PROSTVACNaive CD46.93 Percentage of PBMC
B/ Delayed PROSTVAC TreatmentPeripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC), and naïve CD4 and CD8 T Cells After PROSTVACNK9.28 Percentage of PBMC
B/ Delayed PROSTVAC TreatmentPeripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC), and naïve CD4 and CD8 T Cells After PROSTVACTreg0.59 Percentage of PBMC
B/ Delayed PROSTVAC TreatmentPeripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC), and naïve CD4 and CD8 T Cells After PROSTVACMDSC6.02 Percentage of PBMC
B/ Delayed PROSTVAC TreatmentPeripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC), and naïve CD4 and CD8 T Cells After PROSTVACNaïve CD81.26 Percentage of PBMC
B/ Delayed PROSTVAC TreatmentPeripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC), and naïve CD4 and CD8 T Cells After PROSTVACCD89.98 Percentage of PBMC
B/ Delayed PROSTVAC TreatmentPeripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC), and naïve CD4 and CD8 T Cells After PROSTVACCD429.16 Percentage of PBMC
B/ Delayed PROSTVAC Treatment Day 1Peripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC), and naïve CD4 and CD8 T Cells After PROSTVACNK10.35 Percentage of PBMC
B/ Delayed PROSTVAC Treatment Day 1Peripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC), and naïve CD4 and CD8 T Cells After PROSTVACCD432.44 Percentage of PBMC
B/ Delayed PROSTVAC Treatment Day 1Peripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC), and naïve CD4 and CD8 T Cells After PROSTVACCD812.71 Percentage of PBMC
B/ Delayed PROSTVAC Treatment Day 1Peripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC), and naïve CD4 and CD8 T Cells After PROSTVACTreg1.03 Percentage of PBMC
B/ Delayed PROSTVAC Treatment Day 1Peripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC), and naïve CD4 and CD8 T Cells After PROSTVACMDSC5.74 Percentage of PBMC
B/ Delayed PROSTVAC Treatment Day 1Peripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC), and naïve CD4 and CD8 T Cells After PROSTVACNaive CD47.44 Percentage of PBMC
B/ Delayed PROSTVAC Treatment Day 1Peripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC), and naïve CD4 and CD8 T Cells After PROSTVACNaïve CD81.54 Percentage of PBMC
B/ Delayed PROSTVAC Treatment Day 29Peripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC), and naïve CD4 and CD8 T Cells After PROSTVACTreg0.99 Percentage of PBMC
B/ Delayed PROSTVAC Treatment Day 29Peripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC), and naïve CD4 and CD8 T Cells After PROSTVACNaïve CD81.39 Percentage of PBMC
B/ Delayed PROSTVAC Treatment Day 29Peripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC), and naïve CD4 and CD8 T Cells After PROSTVACNaive CD47.12 Percentage of PBMC
B/ Delayed PROSTVAC Treatment Day 29Peripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC), and naïve CD4 and CD8 T Cells After PROSTVACCD813.00 Percentage of PBMC
B/ Delayed PROSTVAC Treatment Day 29Peripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC), and naïve CD4 and CD8 T Cells After PROSTVACCD429.07 Percentage of PBMC
B/ Delayed PROSTVAC Treatment Day 29Peripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC), and naïve CD4 and CD8 T Cells After PROSTVACMDSC5.52 Percentage of PBMC
B/ Delayed PROSTVAC Treatment Day 29Peripheral Blood Mononuclear Cells (PBMCs) in Cluster of Differentiation 4 (CD4), Cluster of Differentiation 8 (CD8), Regulatory T-cells (Treg), Natural Killer (NK), and Myeloid-derived Suppressor Cells (MDSC), and naïve CD4 and CD8 T Cells After PROSTVACNK10.17 Percentage of PBMC
p-value: 0.2012Wilcoxon signed rank test
p-value: 0.4891Wilcoxon signed rank test
p-value: 0.4609Wilcoxon signed rank test
p-value: 0.0012Wilcoxon signed rank test
p-value: 0.0825Wilcoxon signed rank test
p-value: 0.5988Wilcoxon signed rank test
p-value: 0.592Wilcoxon signed rank test
p-value: 0.6221Wilcoxon signed rank test
p-value: 0.7334Wilcoxon signed rank test
p-value: 0.791Wilcoxon signed rank test
p-value: 0.5186Wilcoxon signed rank test
p-value: 0.5186Wilcoxon signed rank test
p-value: 0.9097Wilcoxon signed rank test
p-value: 0.7334Wilcoxon signed rank test

Source: ClinicalTrials.gov · Data processed: Feb 24, 2026