Active, not recruitingNCT05081193Updated Sep 29, 2026Results posted

Safety and Efficacy of Oral Testosterone Undecanoate Followed by Enzalutamide as Therapy for Men With Metastatic Castrate Resistant Prostate Cancer

A Phase 2 interventional study of Testosterone Undecanoate and Enzalutamide in Prostate Cancer, Castration-resistant Prostate Cancer and Metastatic Castration-resistant Prostate Cancer, sponsored by Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins. Active, not recruiting at 2 sites in United States. Open to male participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-09-29.

Sponsored by Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins · Phase 2, Interventional, and Treatment

Updated Sep 29, 2026Now Active, not recruitingResults posted+2 moreGo to Updates ↓

Phase: Phase 2
Study type: Interventional
Enrollment: 15
Allocation: Not applicable
Ages: 18 Years and older
Sex: Male

Study summary

Previous studies of high dose testosterone therapy given intramuscularly to men with metastatic castrate resistant prostate cancer suggest that high serum levels of testosterone may be required for clinical response. This injection regimen was given as one dose of 400mg injection every 28 days, which initially produces high serum testosterone levels but these levels drop to a varying degree in some men over the 28-day cycle.

In this 30 patient trial will analyze the effects of oral testosterone therapy in men with metastatic castrate resistant prostate cancer taken on a schedule of seven days of oral testosterone therapy followed by seven days of no therapy for a twenty-eight day cycle. This therapy will be given for three 28 day cycles consecutively followed by radiographic scans to evaluate the metastatic disease. Patients will be allowed to continue on this therapy until the patients show signs of radiographic progression. If the patients show signs of radiographic progression after the first three cycles, the patients will stop taking the oral testosterone therapy and begin taking enzalutamide therapy. Enzalutamide therapy will be taken for three 28 day cycles, then radiographic scans will be taken. If there are no signs of radiographic progression, patients can continue to take enzalutamide therapy for an additional 3 cycles while on study. Patients with continued PSA or objective response will come off study but continue on enzalutamide as standard of care therapy.

This study will help the investigators to understand if treating these men with the highest FDA approved dose of oral testosterone therapy will achieve similar and sustained high levels of serum testosterone that will produce similar or enhanced therapeutic response to the therapy when compared to the serum testosterone levels found in the previous injection therapy trials.

Read the detailed description

Metastatic prostate cancer is a highly significant disease that claims the lives of approximately 30,000 American men each year. Androgen Deprivation Therapy (ADT) is initially very effective but is never curative as all men eventually develop castrate resistant prostate cancer (CRPC). A major factor driving resistance is the ability of prostate cancer (PCa) cells to adapt to the chronic low androgen conditions by upregulating androgen receptor (AR) activity through overexpression, gene amplification and expression of truncated, transcriptionally active AR variants that lack the ligand-binding domain. Persistent signaling through AR makes CRPC sensitive to more potent inhibition of AR by abiraterone acetate or second generation anti-androgens such as enzalutamide. Yet these therapies have a limited duration of benefit prior to development of resistance, often through further increase in AR levels.

While this marked upregulation of AR can drive resistance, the investigators have demonstrated that it also creates a therapeutic vulnerability to exposure to high levels of androgen. However, the investigators have also found that sustained exposure of CRPC to supraphysiological levels of androgens results in downregulation of AR and acquired resistance to this therapy. Therefore the investigators have developed a therapy called Bipolar Androgen Therapy (BAT) in which testosteronecypionate 400 mg IM is administered every 28 days to result in cycling from supraphysiological (>1500 ng/dL) to near-castrate levels. The rationale for cycling was that high serum T would kill high AR expressing CRPC while low serum T would prevent adaptation to high T and kill low AR expressing CRPC.

To date the investigators have treated approximately 250 men with BAT across four completed studies in asymptomatic men with CRPC. The key findings have been that BAT: (a) could be safely administered; (b) did not produce symptomatic disease progression; (c) produced sustained PSA and objective responses in approximately 30-40% of patients; (d) re-sensitized and prolonged response of patients to subsequent antiandrogen therapy. While ADT for advanced PCa often produces debilitating sexual and metabolic side effects, another highly significant feature of this approach is that BAT can make men feel remarkably better by decreasing fatigue, increasing physical activity and restoring libido and sexual function. BAT also produced favorable effects on body composition by increasing skeletal muscle mass and decreasing subcutaneous and visceral fat. Thus, incorporation of BAT into the treatment paradigm has the potential to improve the quality of life and well-being of PCa patients and minimize the morbidity from the metabolic sequelae produced by androgen ablative therapies.

The studies performed to date demonstrate the safety and efficacy of high dose T in men with metastatic CRPC who are progressing on androgen ablative therapy. The investigators' limited data suggests that high serum levels of T may be required for clinical response. This high level has is achieved through intramuscular (IM) administration of testosterone cypionate at the highest FDA-approved dose of 400 mg every 28 days. This regimen initially produces high serum T levels but these levels drop to a varying degrees approaching near castrate levels in some men over a 28-day cycle. To date, the investigators have not tested whether more rapid cycling of serum T would produce similar or improved therapeutic response in this patient population. Additional issues with IM testosterone are (1) it requires patients to come to hospital every 28 days for injection, (2) has highly variable pharmacokinetics, (3) can cause physical discomfort from IM injections.

Recently two novel oral testosterone (OT) agents were developed for the treatment of male hypogonadism. Historically, an oral option for testosterone replacement therapy was unavailable because of risks of liver toxicity, including cholestasis and jaundice, associated with earlier developed 17-alpha-alkylated oral analogs. These novel oral agents feature specialized formulations that avoid adverse hepatic effects. In clinical trials, both oral agents produced no significant adverse effects on liver function tests. The investigators have formed a collaborative partnership with Clarus Therapeutics, the makers of Jatenzo, an oral lipoprotein-coated testosterone undecanoate (OT) formulation that was FDA-approved in December 2019 as T-replacement therapy. Published pharmacokinetic data demonstrate that OT can produce supraphysiologic serum T levels when administered at the highest FDA-approved dose. Therefore, the investigators' hypothesis is that OT, given at the highest FDA approved dose, will achieve more homogeneous and sustained supraphysiologic levels of serum T that will produce similar or enhanced therapeutic response. To avoid adaptation of CRPC to this sustained level of T, the investigators will utilize a dosing schedule of 1 week-on, 1 week-off.

Conditions studied

Prostate Cancer
Castration-resistant Prostate Cancer
Metastatic Castration-resistant Prostate Cancer

Browse trials for

Prostatic Neoplasms 6,370

Keywords

Oral Testosterone Therapy
Enzalutamide

In context

Prostatic Neoplasms

6,370 studies on the registry are indexed under Prostatic Neoplasms; 1,400 are open to participants now.

This study's enrollment of 15 is below the median of 58 across 4,822 interventional studies indexed under Prostatic Neoplasms.

Browse Prostatic Neoplasms studies →

Lead sponsor

Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins is the lead sponsor of 572 studies on the registry; 73 are open to participants now.

Of its 111 completed or terminated interventional studies of FDA-regulated products, 67 (60%) have results posted.

Counted across the registry records on this site, refreshed daily.

Who can participate

Ages eligible: 18 Years and older
Sexes eligible: Male
Accepts healthy volunteers: No

Inclusion criteria

Patient has the ability to understand and willingness to sign a written informed consent document.
Patient is a male aged 18 years or older.
Patient has histologically-confirmed adenocarcinoma of the prostate
Patient has an Eastern Cooperative Oncology Group (ECOG) performance status of ≤2 (as defined in Appendix A: Performance Status Criteria;
Patient has evidence of metastatic, measurable disease by CT scan. Measurable disease is defined by RECIST 1.1 as at least one measurable lesion ≥10mm by CT scan
Patient is progressing on continuous androgen ablative therapy (either surgical castration or LHRH agonist/antagonist)
Patient has documented castrate level of serum testosterone (\<50 ng/dl)
Patient is progressing on luteinizing hormone-releasing hormone (LHRH) agonist/antagonist plus anti-androgen or abiraterone for CSPC. (Note: Must be off anti-androgen or abiraterone for 4 weeks prior to first treatment with OT.) LHRH (luteinizing hormone-releasing hormone)
Patient has had prior docetaxel for CSPC. Note: Docetaxel is permitted if ≤ 6 doses were given in conjunction with first-line androgen deprivation therapy and >6 months since last dose of docetaxel. (CSPC-castrate sensitive prostate cancer)
Patient is currently taking prednisone and cannot be weaned entirely off. Note: Patient's dose must be maintained on lowest stable dose that relieves symptoms. Patient is receiving prednisone in conjunction with abiraterone acetate must be weaned off prednisone if possible prior to starting OT.
Patient has had a rising PSA on two successive measurements at least two weeks apart.
Patient agrees to continue on castrating therapy throughout OT treatment.
Patient's screening lab values are within the following parameters:
1. Absolute neutrophil count (ANC) ≥ 1500 cells/mm3 (1.5 ×109/L)
2. Platelet count ≥ 100,000 platelet/mm3 (100 ×109/L)
3. Hemoglobin ≥ 9 g/dL
4. Serum creatinine \< 2.5 times ULN
5. Bilirubin \< 2.5 times institutional upper limit of normal (ULN)
6. Aspartate aminotransferase (AST) and Alanine Aminotransferase (ALT) \< 2.5 times ULN
Patient has had surgery, has completed at least 4 weeks of recovery and has no persistent toxicity > grade 1.

Exclusion criteria

Exclusion Criteria:

Patient has pain due to metastatic prostate cancer requiring opioid analgesics.
Patient has had prior treatment with any agent for metastatic castration-resistant prostate cancer. (Includes docetaxel, cabazitaxel, anti-androgen, abiraterone, or investigational agents)
Patient requires urinary catheterization for voiding due to obstruction secondary to prostatic enlargement thought to be due to prostate cancer or benign prostatic hyperplasia. Note: Patients with indwelling catheter/suprapubic catheter to relieve obstruction are eligible.
Patient has evidence of disease in sites or extent that, in the opinion of the investigator, would put the patient at risk from therapy with testosterone (e.g. femoral metastases with concern over fracture risk, epidural spinal metastases with concern over spinal cord compression, lymph node disease with concern for ureteral obstruction).
Patient has evidence of disease in sites or extent that, in the opinion of the investigator, would put the patient at risk from therapy with testosterone (e.g. femoral metastases with concern over fracture risk, epidural spinal metastases with concern over spinal cord compression, lymph node disease with concern for ureteral obstruction).
Patient has active uncontrolled infection, such as HIV/AIDS or chronic hepatitis B or untreated chronic hepatitis C.
Patient has had prior history of a thromboembolic event within the past two years and not currently on systemic anticoagulation.
Patient is on Coumadin. Note: If anticoagulation therapy is mandatory, patient must be switched to an alternative medication) Patients receiving anticoagulation therapy with warfarin, rivaroxaban or apixaban are not eligible for study. [Patients on enoxaparin or edoxaban are eligible for study. Patients on warfarin, rivaroxaban or apixaban, who can be transitioned to enoxaparin prior to starting study treatments, will be eligible.
Patient has hematocrit >50%, untreated severe obstructive sleep apnea, uncontrolled or poorly controlled heart failure [per Endocrine Society Clinical Practice Guidelines].

Study design

Phase: Phase 2
Primary purpose: Treatment
Allocation: Not applicable
Intervention model: Single group
Masking: None (open label)
Enrollment: 15 participants (actual)

Study arms

Experimental
Oral Testosterone Therapy given until radiographic progression followed by Enzalutamide Therapy
Oral Testosterone Therapy-396 mg given twice per day on days 1-7 and 15-21 of a 28 day cycle until radiographic progression. After a 21 day washout period, Enzalutamide therapy given at 160 mg once daily will be taken for a maximum of 6 cycles while on study.
Drug: Testosterone Undecanoate · Drug: Enzalutamide

Interventions

DrugTestosterone Undecanoate
198mg taken twice daily
Also known as: Jatenzo
DrugEnzalutamide
160mg taken once daily
Also known as: Xtandi

What researchers measure

Primary outcomes

Objective Response Rate of Oral Testosterone Undecanoate (CT Scan)
Radiographic responses to Oral Testosterone therapy using CT scan measurements. Radiographic progression is assessed by RECIST (Response Evaluation Criteria in Solid Tumors). Per RECIST, progression is defined as ≥ 20% and ≥ 5 mm from nadir of the sum of the diameters of target lesions.
Time frame: Up to 2 years post Oral Testosterone

Secondary outcomes

PSA50 Response to Oral Testosterone Therapy
Number of participants with PSA50 response to Oral Testosterone therapy defined as at least a 50% decline in Prostate Specific Antigen (PSA) from baseline value.
Time frame: Up to 2 years post Oral Testosterone
Time to PSA Progression While on Oral Testosterone
Number of months from baseline until PSA progression
Time frame: Up to 2 years post Oral Testosterone
Time to Clinical or Radiographic Progression While on Oral Testosterone
Number of months from baseline until radiographic or clinical progression, whichever comes first. Radiographic progression is assessed by Response Evaluation Criteria in Solid Tumors (RECIST) and Prostate Cancer Working Group 3 (PCWG3) criteria. Per RECIST, progression is defined as ≥ 20% and ≥ 5 mm from nadir of the sum of the diameters of target lesions. Per PCWG3 criteria, radiographic progression is defined as ≥ 20% sum of the longest diameter of target lesions, or ≥ 2 new lesions on bone scan from baseline. Clinical progression is defined as new spinal cord or nerve root compression, new pathologic fracture or use of opioid analgesics for cancer-related pain.
Time frame: Up to 2 years post Oral Testosterone
PSA50 Response to Enzalutamide Therapy
Number of participants with PSA50 response to enzalutamide therapy defined as at least a 50% decline in Prostate Specific Antigen (PSA) from baseline value.
Time frame: Up to 2 years post Enzalutamide
Objective Response Rate of Enzalutamide Therapy (CT Scan)
Radiographic responses to Enzalutamide therapy using CT scan measurements after 3 cycles and after 6 cycles of therapy. Radiographic progression is assessed by RECIST (Response Evaluation Criteria in Solid Tumors) criteria ). Per RECIST, progression is defined as ≥ 20% and ≥ 5 mm from nadir of the sum of the diameters of target lesions.
Time frame: Up to 2 years post Enzalutamide
Trough Testosterone Level
Mean trough testosterone level (ng/dL) measured within 24, 48, 72 or 96 hours after cycle 1 day 7 dose of oral testosterone therapy
Time frame: Up to 96 hours after cycle 1 day 7 dose
PBMC Immunologic and Metabolic Phenotype
Phenotype of peripheral blood mononucleated cell (PBMC) as defined by number of cluster of differentiation 4 (CD4) Tcells, cluster of differentiation 8 (CD8) Tcells, FOXP3+ Treg cells, B cells, Natural Killer (NK) cells, monocytes, dendritic cells, and myeloid derived suppressor cells. PBMCs will be immunophenotyped using multiparameter flow cytometry.
Time frame: 2 years
Change in Quality of Life as Assessed by The-FACIT-Fatigue Questionnaire
The Functional Assessment of Chronic Illness Therapy - Fatigue has a score range of 0-52 with higher scores indicating better quality of life.
Time frame: Up to 2 years post Oral Testosterone
Change in Quality of Life as Assessed by the- Short Form 36 (SF-36) Questionnaire
All questions are scored on a scale from 0 to 100. The total score from all of the questions answered is divided by the total number of the questions answered yielding a global score from 0-100 with 100 representing the highest level of functioning possible.
Time frame: Up to 2 years post Oral Testosterone
Safety of Trial Therapy as Assessed by Adverse Event Reporting
Safety as assessed by related adverse event reporting. Grading of adverse events will be done by utilizing the NCI Common Terminology Criteria for Adverse Events (CTCAE) v4.03. Determination of relationship of the adverse event to the study procedures or study drug will be performed by the PI using the standard attribution terminology (e.g. unrelated, possibly related, etc.).
Time frame: Up to 28 days post all treatment
Tolerability of Trial Therapy as Assessed by Adverse Event Reporting
Tolerability as assessed by related adverse event reporting. Grading of adverse events will be done by utilizing the NCI Common Terminology Criteria for Adverse Events (CTCAE) v4.03. Determination of relationship of the adverse event to the study procedures or study drug will be performed by the PI using the standard attribution terminology (e.g. unrelated, possibly related, etc.).
Time frame: Up to 28 days post all treatment
Time to PSA Progression While on Enzalutamide
Number of weeks from start of enzalutamide treatment until PSA progression.
Time frame: Up to 2 years post enzalutamide
Time to PSA Progression While on Enzalutamide From Start of Oral Testosterone Therapy
Number of weeks from start of oral testosterone therapy until PSA progression while on enzalutamide treatment.
Time frame: Up to 2 years post all treatment

Results

Posted Sep 29, 2026

Participant flow

Intervention 1 (1 Year)

Participant flow — Intervention 1 (1 Year)
Milestone	Oral Testosterone Undecanoate Followed by Enzalutamide as Therapy
Started	15
Completed	12
Not completed	3
Withdrew: Did not start treatment	2
Withdrew: Withdrawal by subject	1

Washout (21 Days)

Participant flow — Washout (21 Days)
Milestone	Oral Testosterone Undecanoate Followed by Enzalutamide as Therapy
Started	11
Completed	11
Not completed	0

Intervention 2 (90 Days)

Participant flow — Intervention 2 (90 Days)
Milestone	Oral Testosterone Undecanoate Followed by Enzalutamide as Therapy
Started	10
Completed	10
Not completed	0

Outcome measures

PrimaryObjective Response Rate of Oral Testosterone Undecanoate (CT Scan)

Radiographic responses to Oral Testosterone therapy using CT scan measurements. Radiographic progression is assessed by RECIST (Response Evaluation Criteria in Solid Tumors). Per RECIST, progression is defined as ≥ 20% and ≥ 5 mm from nadir of the sum of the diameters of target lesions.

Time frame:: Up to 2 years post Oral Testosterone
Reported as:: Count of participants · Participants

Objective Response Rate of Oral Testosterone Undecanoate (CT Scan)
Participants	Oral Testosterone Undecanoate Followed by Enzalutamide as Therapy
Objective Response Rate of Oral Testosterone Undecanoate (CT Scan)	2

SecondaryPSA50 Response to Oral Testosterone Therapy

Number of participants with PSA50 response to Oral Testosterone therapy defined as at least a 50% decline in Prostate Specific Antigen (PSA) from baseline value.

Time frame:: Up to 2 years post Oral Testosterone
Reported as:: Count of participants · Participants

PSA50 Response to Oral Testosterone Therapy
Participants	Oral Testosterone Undecanoate Followed by Enzalutamide as Therapy
PSA50 Response to Oral Testosterone Therapy	4

SecondaryTime to PSA Progression While on Oral Testosterone

Number of months from baseline until PSA progression

Time frame:: Up to 2 years post Oral Testosterone
Reported as:: Median · months

Time to PSA Progression While on Oral Testosterone
months	Oral Testosterone Undecanoate Followed by Enzalutamide as Therapy
Time to PSA Progression While on Oral Testosterone	4.7 (1.87 to 7.43)

SecondaryTime to Clinical or Radiographic Progression While on Oral Testosterone

Number of months from baseline until radiographic or clinical progression, whichever comes first. Radiographic progression is assessed by Response Evaluation Criteria in Solid Tumors (RECIST) and Prostate Cancer Working Group 3 (PCWG3) criteria. Per RECIST, progression is defined as ≥ 20% and ≥ 5 mm from nadir of the sum of the diameters of target lesions. Per PCWG3 criteria, radiographic progression is defined as ≥ 20% sum of the longest diameter of target lesions, or ≥ 2 new lesions on bone scan from baseline. Clinical progression is defined as new spinal cord or nerve root compression, new pathologic fracture or use of opioid analgesics for cancer-related pain.

Time frame:: Up to 2 years post Oral Testosterone
Reported as:: Median · months

Time to Clinical or Radiographic Progression While on Oral Testosterone
months	Oral Testosterone Undecanoate Followed by Enzalutamide as Therapy
Time to Clinical or Radiographic Progression While on Oral Testosterone	5.6 (2.8 to NA)

SecondaryPSA50 Response to Enzalutamide Therapy

Number of participants with PSA50 response to enzalutamide therapy defined as at least a 50% decline in Prostate Specific Antigen (PSA) from baseline value.

Time frame:: Up to 2 years post Enzalutamide
Reported as:: Count of participants · Participants

PSA50 Response to Enzalutamide Therapy
Participants	Oral Testosterone Undecanoate Followed by Enzalutamide as Therapy
PSA50 Response to Enzalutamide Therapy	7

SecondaryObjective Response Rate of Enzalutamide Therapy (CT Scan)

Radiographic responses to Enzalutamide therapy using CT scan measurements after 3 cycles and after 6 cycles of therapy. Radiographic progression is assessed by RECIST (Response Evaluation Criteria in Solid Tumors) criteria ). Per RECIST, progression is defined as ≥ 20% and ≥ 5 mm from nadir of the sum of the diameters of target lesions.

Time frame:: Up to 2 years post Enzalutamide
Reported as:: Count of participants · Participants

Objective Response Rate of Enzalutamide Therapy (CT Scan)
Participants	Oral Testosterone Undecanoate Followed by Enzalutamide as Therapy
Objective Response Rate of Enzalutamide Therapy (CT Scan)	5

SecondaryTrough Testosterone Level

Mean trough testosterone level (ng/dL) measured within 24, 48, 72 or 96 hours after cycle 1 day 7 dose of oral testosterone therapy

Time frame:: Up to 96 hours after cycle 1 day 7 dose
Reported as:: Median · ng/dL

Trough Testosterone Level
ng/dL	Oral Testosterone Undecanoate Followed by Enzalutamide as Therapy
Trough Testosterone Level	471.5 ± 229

SecondaryPBMC Immunologic and Metabolic Phenotype

Phenotype of peripheral blood mononucleated cell (PBMC) as defined by number of cluster of differentiation 4 (CD4) Tcells, cluster of differentiation 8 (CD8) Tcells, FOXP3+ Treg cells, B cells, Natural Killer (NK) cells, monocytes, dendritic cells, and myeloid derived suppressor cells. PBMCs will be immunophenotyped using multiparameter flow cytometry.

Time frame:: 2 years

Results for this outcome have not been posted.

SecondaryChange in Quality of Life as Assessed by The-FACIT-Fatigue Questionnaire

The Functional Assessment of Chronic Illness Therapy - Fatigue has a score range of 0-52 with higher scores indicating better quality of life.

Time frame:: Up to 2 years post Oral Testosterone
Reported as:: Mean · score on a scale

Change in Quality of Life as Assessed by The-FACIT-Fatigue Questionnaire
score on a scale	Oral Testosterone Undecanoate Followed by Enzalutamide as Therapy
Change in Quality of Life as Assessed by The-FACIT-Fatigue Questionnaire	-0.333 ± 5.39

SecondaryChange in Quality of Life as Assessed by the- Short Form 36 (SF-36) Questionnaire

All questions are scored on a scale from 0 to 100. The total score from all of the questions answered is divided by the total number of the questions answered yielding a global score from 0-100 with 100 representing the highest level of functioning possible.

Time frame:: Up to 2 years post Oral Testosterone
Reported as:: Mean · score on a scale

Change in Quality of Life as Assessed by the- Short Form 36 (SF-36) Questionnaire
score on a scale	Oral Testosterone Undecanoate Followed by Enzalutamide as Therapy
Change in Quality of Life as Assessed by the- Short Form 36 (SF-36) Questionnaire	-1.6 ± 12.6

SecondarySafety of Trial Therapy as Assessed by Adverse Event Reporting

Safety as assessed by related adverse event reporting. Grading of adverse events will be done by utilizing the NCI Common Terminology Criteria for Adverse Events (CTCAE) v4.03. Determination of relationship of the adverse event to the study procedures or study drug will be performed by the PI using the standard attribution terminology (e.g. unrelated, possibly related, etc.).

Time frame:: Up to 28 days post all treatment
Reported as:: Number · related events

Safety of Trial Therapy as Assessed by Adverse Event Reporting
related events	Oral Testosterone Undecanoate Followed by Enzalutamide as Therapy
Safety of Trial Therapy as Assessed by Adverse Event Reporting	6

SecondaryTolerability of Trial Therapy as Assessed by Adverse Event Reporting

Tolerability as assessed by related adverse event reporting. Grading of adverse events will be done by utilizing the NCI Common Terminology Criteria for Adverse Events (CTCAE) v4.03. Determination of relationship of the adverse event to the study procedures or study drug will be performed by the PI using the standard attribution terminology (e.g. unrelated, possibly related, etc.).

Time frame:: Up to 28 days post all treatment
Reported as:: Number · related events

Tolerability of Trial Therapy as Assessed by Adverse Event Reporting
related events	Oral Testosterone Undecanoate Followed by Enzalutamide as Therapy
Tolerability of Trial Therapy as Assessed by Adverse Event Reporting	6

SecondaryTime to PSA Progression While on Enzalutamide

Number of weeks from start of enzalutamide treatment until PSA progression.

Time frame:: Up to 2 years post enzalutamide

Results for this outcome have not been posted.

SecondaryTime to PSA Progression While on Enzalutamide From Start of Oral Testosterone Therapy

Number of weeks from start of oral testosterone therapy until PSA progression while on enzalutamide treatment.

Time frame:: Up to 2 years post all treatment

Results for this outcome have not been posted.

Adverse events

Collected over from the start of treatment up to 2 years post treatment. Non-serious events are listed at a 5% frequency threshold.

Adverse event summary by group
Group	Deaths	Serious	Other
Oral Testosterone Therapy Given Until Radiographic Progression Followed by Enzalutamide Therapy	0/15 (0%)	2/15 (13.3%)	10/15 (66.7%)

Most frequent serious events

Most frequent serious events
Event	Oral Testosterone Therapy Given Until Radiographic Progression Followed by Enzalutamide Therapy
Back PainMusculoskeletal and connective tissue disorders	1/15
Chest wall painMusculoskeletal and connective tissue disorders	1/15

Most frequent other events

Showing 10 of 30

Most frequent other events
Event	Oral Testosterone Therapy Given Until Radiographic Progression Followed by Enzalutamide Therapy
HeadacheNervous system disorders	3/15
FatigueGeneral disorders	3/15
DiarrheaGastrointestinal disorders	3/15
Urinary frequencyRenal and urinary disorders	2/15
Flu like symptomsGeneral disorders	2/15
Creatinine increasedInvestigations	2/15
Back painMusculoskeletal and connective tissue disorders	2/15
AnorexiaMetabolism and nutrition disorders	2/15
VomitingGastrointestinal disorders	1/15
Upper respiratory infectionInfections and infestations	1/15

Baseline characteristics

Age, Categorical
Age, Categorical(Participants)	Oral Testosterone Therapy Given Until Radiographic Progression Followed by Enzalutamide Therapy
<=18 years	0
Between 18 and 65 years	2
>=65 years	10

Age, Continuous
Age, Continuous(years)	Oral Testosterone Therapy Given Until Radiographic Progression Followed by Enzalutamide Therapy
Mean	71.5 (60 to 85)

Sex: Female, Male
Sex: Female, Male(Participants)	Oral Testosterone Therapy Given Until Radiographic Progression Followed by Enzalutamide Therapy
Female	0
Male	12

Ethnicity (NIH/OMB)
Ethnicity (NIH/OMB)(Participants)	Oral Testosterone Therapy Given Until Radiographic Progression Followed by Enzalutamide Therapy
Hispanic or Latino	0
Not Hispanic or Latino	12
Unknown or Not Reported	0

Race (NIH/OMB)
Race (NIH/OMB)(Participants)	Oral Testosterone Therapy Given Until Radiographic Progression Followed by Enzalutamide Therapy
American Indian or Alaska Native	0
Asian	0
Native Hawaiian or Other Pacific Islander	0
Black or African American	4
White	8
More than one race	0
Unknown or Not Reported	0

Region of Enrollment
Region of Enrollment(Participants)	Oral Testosterone Therapy Given Until Radiographic Progression Followed by Enzalutamide Therapy
United States	12

Study locations

2 sites

Johns Hopkins Hospital
Baltimore, Maryland 21231, United States
Allegheny Health Network
Pittsburgh, Pennsylvania 15212, United States

References and documents

Study documents

Protocol and statistical analysis plan · Feb 7, 2023

Documents are hosted by the registry — open the source record to download them.

Updates

1 registry update since Sep 25, 2026

Status

Completed→Active, not recruiting

changed Sep 29, 2026

Results

Results posted

posted Sep 29, 2026

Study completion

Aug 4, 2025→Dec 4, 2026

Sep 29, 2026

Also revised

primary outcomes

Show all 1 update

Sep 29, 2026
Completed→Active, not recruiting
Results posted
Study completion Aug 4, 2025→Dec 4, 2026
Primary outcomes Revised (1 change)
+ 4 other changes: index terms, verification date, secondary outcomes and documents

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 ↗

Registry details

Key details

Study ID: NCT05081193
Lead sponsor: Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins
Collaborators: Clarus Therapeutics, Inc., Allegheny Health Network
Responsible party: Sponsor
First posted: Oct 18, 2021
Start date: Mar 7, 2022
Primary completion: Aug 4, 2025
Completion: Dec 4, 2026 (estimated)
Results posted: Sep 29, 2026
Last update: Sep 29, 2026

Study contacts

Samuel Denmeade, MD

principal investigator · Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins

Oversight

Data monitoring committee: Yes
FDA-regulated drug: Yes
FDA-regulated device: No

View the source record on ClinicalTrials.gov ↗

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Safety and Efficacy of Oral Testosterone Undecanoate Followed by Enzalutamide as Therapy for Men With Metastatic Castrate Resistant Prostate Cancer

Study summary

Conditions studied

Browse trials for

Keywords

In context

Prostatic Neoplasms

Lead sponsor

Who can participate

✓Inclusion criteria

✕Exclusion criteria

Study design

Study arms

Interventions

What researchers measure

Primary outcomes

Secondary outcomes

Results

Participant flow

Outcome measures

Adverse events

Baseline characteristics

Study locations

References and documents

Study documents

Updates

Registry details

Key details

Study contacts

Oversight

Not currently enrolling

Follow this study

Discussion

Other studies in this condition

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Inclusion criteria

Exclusion criteria