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Active, not recruitingNCT04497844AMPLITUDEUpdated Nov 4, 2026Results posted

A Study of Niraparib in Combination With Abiraterone Acetate and Prednisone Versus Abiraterone Acetate and Prednisone for the Treatment of Participants With Deleterious Germline or Somatic Homologous Recombination Repair (HRR) Gene-MutatedProstatic Neoplasms (mCSPC)

A Phase 3 interventional study of Niraparib+ Abiraterone acetate fixed dose combination (FDC) and Abiraterone acetate (AA) in Prostatic Neoplasms, sponsored by Janssen Research & Development, LLC. Active, not recruiting at 387 sites in 33 countries. Open to male participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-11-04.

Sponsored by Janssen Research & Development, LLC (part of Johnson & Johnson) · Phase 3, Interventional, and Treatment

Phase
Phase 3
Study type
Interventional
Enrollment
696
Allocation
Randomized
Ages
18 Years and older
Sex
Male
01

Study summary

The purpose of the study is to determine if the combination of niraparib with Abiraterone Acetate (AA) plus prednisone compared with AA plus prednisone in participants with deleterious germline or somatic Homologous Recombination Repair (HRR) gene-mutated Metastatic Castration-Sensitive Prostate Cancer (mCSPC) provides superior efficacy in improving radiographic progression-free survival (rPFS).

02

Conditions studied

  • Prostatic Neoplasms

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03

In context

Prostatic Neoplasms

7,046 studies on the registry are indexed under Prostatic Neoplasms; 1,580 are open to participants now.

This study's enrollment of 696 is above the median of 60 across 5,348 interventional studies indexed under Prostatic Neoplasms.

Browse Prostatic Neoplasms studies →

Lead sponsor

Janssen Research & Development, LLC is the lead sponsor of 932 studies on the registry; 76 are open to participants now.

Of its 285 completed or terminated interventional studies of FDA-regulated products, 136 (48%) have results posted.

Browse Janssen Research & Development, LLC studies →All Johnson & Johnson studies →

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

04

Who can participate

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

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.

Inclusion criteria

  • Pathological diagnosis of prostate adenocarcinoma
  • Must have appropriate deleterious homologous recombination repair (HRR) gene alteration
  • disease as documented by conventional imaging with computed tomography (CT) or magnetic resonance imaging (MRI) (for soft tissue lesions) or 99mTc bone scan (for bone lesions). Participants with a single bone lesion on Technetium-99m (99mTc) bone scan with no other non-nodal metastatic disease must have confirmation of bone metastasis by CT or MRI. Participants with lymph node-only disease are not eligible
  • Androgen deprivation therapy (either medical or surgical castration) must have been started >=14 days prior to randomization and participants be willing to continue androgen deprivation therapy (ADT) through the treatment phase
  • Other allowed prior therapy for metastatic castration-sensitive prostate cancer (mCSPC): (a) maximum of 1 course of radiation and 1 surgical intervention for symptomatic control of prostate cancer (example, uncontrolled pain, impending spinal cord compression or obstructive symptoms). Participants with radiation or surgical interventions to all known sites of metastatic disease will be excluded from trial participation. Radiation must be completed prior to randomization (b) Up to a maximum of 6 months of ADT prior to randomization; (c) Up to a maximum of 45 days of abiraterone acetate + prednisone (AA-P) prior to randomization (d) Up to a maximum of 2 weeks of ketoconazole for prostate cancer prior to randomization

Exclusion criteria

Exclusion criteria:

  • Prior treatment with a poly (adenosine diphosphate-ribose) polymerase inhibitor (PARP inhibitor)
  • History of adrenal dysfunction
  • Long-term use of systemically administered (greater than [>] 5 milligrams [mg] of prednisone or the equivalent) during the study is not allowed. Short-term use (\<=4 weeks, including taper) and locally administered steroids (for example, inhaled, topical, ophthalmic, and intra-articular) are allowed, if clinically indicated
  • History or current diagnosis of myelodysplastic syndrome (MDS)/ acute myeloid leukemia (AML)
Terms in these criteria, in plain language(2)

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.

Metastases

Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.

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.

05

Study design

Phase
Phase 3
Primary purpose
Treatment
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Triple (Participant, Investigator, Outcomes assessor)
Enrollment
696 participants (actual)

Study arms

  • Experimental
    Niraparib with Abiraterone Acetate plus Prednisone (AAP)

    Participants will receive the following in each 28-day treatment cycle: niraparib 200 milligrams (mg) + abiraterone acetate (AA) 1000 mg fixed dose combination (FDC) along with placebo for AA and prednisone 5 mg once daily.

    Combination Product: Niraparib+ Abiraterone acetate fixed dose combination (FDC) · Drug: Prednisone · Drug: Placebo AA

  • Active comparator
    Placebo for Niraparib + AA FDC plus AA and prednisone (AAP)

    Participants will receive the following in each 28-day treatment cycle: matching placebo for Niraparib+AA FDC along with AA 1000 mg and prednisone 5 mg once daily.

    Drug: Abiraterone acetate (AA) · Drug: Prednisone · Drug: Placebo FDC

Interventions

  • Combination productNiraparib+ Abiraterone acetate fixed dose combination (FDC)

    Drug pages: Niraparib · Abiraterone Acetate

    Participants will receive a FDC of Niraparib 200 mg + AA 1000 mg once daily.

  • DrugAbiraterone acetate (AA)

    Participants will receive AA 1000 mg once daily.

  • DrugPrednisone

    Participants will receive prednisone 5 mg once daily.

  • DrugPlacebo FDC

    Participants will receive matching placebo for Niraparib +AA FDC once daily.

  • DrugPlacebo AA

    Participants will receive matching placebo for AA once daily.

06

What researchers measure

Primary outcomes

  1. Breast Cancer Gene (BRCA) Subgroup: Radiographic Progression-free Survival (rPFS) Assessed by Investigator

    rPFS: time interval from date of randomization to first date of radiographic progression as assessed by investigator or death due to any cause, whichever occurred first. rPFS was determined by: (1) progression of soft tissue lesions measured by computerized tomography (CT) or magnetic resonance imaging (MRI) per response evaluation criteria in solid tumors (RECIST) 1.1; (2) progression of bone lesions observed by bone scan per prostate cancer working group 3 (PCWG3) criteria: bone progression was confirmed by subsequent scan greater than or equal to (\>=) 6 weeks later. Week 8 scan was baseline to which all subsequent scans were compared to determine progression. A confirmatory scan with \>=2 new lesions indicated progression; A confirmatory scan not showing \>=2 new lesions means no progression. If Week 8 scan shows \<2 new bone lesions compared to baseline, first scan with \>=2 new lesions compared to Week 8 scan indicated progression, when confirmed by a subsequent scan \>=6 weeks later.

    Time frame: From date of randomization (Day -3 to Day 1) up to approximately 49 months

  2. HRR Effector Subgroup: Radiographic Progression-free Survival (rPFS) Assessed by Investigator

    rPFS: time interval from date of randomization to first date of radiographic progression as assessed by investigator or death due to any cause, whichever occurred first. rPFS was determined by: (1) progression of soft tissue lesions measured by CT or MRI per RECIST 1.1; (2) progression of bone lesions observed by bone scan per PCWG3 criteria: bone progression was confirmed by subsequent scan \>= 6 weeks later. Week 8 scan was baseline to which all subsequent scans were compared to determine progression. A confirmatory scan with \>=2 new lesions indicated progression; A confirmatory scan not showing \>=2 new lesions means no progression. If Week 8 scan shows \<2 new bone lesions compared to baseline, first scan with \>=2 new lesions compared to Week 8 scan indicated progression, when confirmed by a subsequent scan \>=6 weeks later.

    Time frame: From date of randomization (Day -3 to Day 1) up to approximately 49 months

  3. All HRR: Radiographic Progression-free Survival (rPFS) Assessed by Investigator

    rPFS: time interval from date of randomization to first date of radiographic progression as assessed by investigator or death due to any cause, whichever occurred first. rPFS was determined by: (1) progression of soft tissue lesions measured by CT or MRI per RECIST 1.1; (2) progression of bone lesions observed by bone scan per PCWG3 criteria: bone progression was confirmed by subsequent scan \>= 6 weeks later. Week 8 scan was baseline to which all subsequent scans were compared to determine progression. A confirmatory scan with \>=2 new lesions indicated progression; A confirmatory scan not showing \>=2 new lesions means no progression. If Week 8 scan shows \<2 new bone lesions compared to baseline, first scan with \>=2 new lesions compared to Week 8 scan indicated progression, when confirmed by a subsequent scan \>=6 weeks later.

    Time frame: From date of randomization (Day -3 to Day 1) up to approximately 49 months

Secondary outcomes

  1. BRCA Subgroup: Time to Symptomatic Progression

    Time to symptomatic progression was defined as time from the date of randomization to the date of any of the following (whichever occurred first): (a) the use of external beam radiation therapy for skeletal or pelvic symptoms, (b) the need for tumor-related orthopedic surgical intervention, (c) other cancer-related procedures (example: nephrostomy insertion, bladder catheter insertion, external beam radiation therapy, or surgery for tumor symptoms), (d) cancer-related morbid events (that is, fracture \[symptomatic and/or pathologic\], cord compression, urinary obstructive events), (e) initiation of a new systemic anti-cancer therapy because of cancer symptoms.

    Time frame: From date of randomization (Day -3 to Day 1) up to approximately 49 months

  2. HRR Effector Subgroup: Time to Symptomatic Progression

    Time to symptomatic progression was defined as time from the date of randomization to the date of any of the following (whichever occurred first): (a) the use of external beam radiation therapy for skeletal or pelvic symptoms, (b) the need for tumor-related orthopedic surgical intervention, (c) other cancer-related procedures (example: nephrostomy insertion, bladder catheter insertion, external beam radiation therapy, or surgery for tumor symptoms), (d) cancer-related morbid events (that is, fracture \[symptomatic and/or pathologic\], cord compression, urinary obstructive events), (e) initiation of a new systemic anti-cancer therapy because of cancer symptoms.

    Time frame: From date of randomization (Day -3 to Day 1) up to approximately 49 months

  3. All HRR: Time to Symptomatic Progression

    Time to symptomatic progression was defined as time from the date of randomization to the date of any of the following (whichever occurred first): (a) the use of external beam radiation therapy for skeletal or pelvic symptoms, (b) the need for tumor-related orthopedic surgical intervention, (c) other cancer-related procedures (example: nephrostomy insertion, bladder catheter insertion, external beam radiation therapy, or surgery for tumor symptoms), (d) cancer-related morbid events (that is, fracture \[symptomatic and/or pathologic\], cord compression, urinary obstructive events), (e) initiation of a new systemic anti-cancer therapy because of cancer symptoms.

    Time frame: From date of randomization (Day -3 to Day 1) up to approximately 49 months

  4. Overall Survival (OS)

    Time frame: From date of randomization (Day -3 to Day 1) up to 83 months

  5. Time to Subsequent Therapy

    Time frame: From date of randomization (Day -3 to Day 1) up to 83 months

  6. Number of Participants With Treatment-emergent Serious Adverse Events

    Time frame: From Cycle 1 Day 1 up to 83 months

  7. Number of Participants With Treatment-emergent Adverse Events by Severity

    Time frame: From Cycle 1 Day 1 up to 83 months

07

Results

Posted Jan 22, 2026

Participant flow

Participant flow — Overall Study
MilestonePlacebo With Abiraterone Acetate Plus PrednisoneNiraparib With Abiraterone Acetate Plus Prednisone
Started348348
Treated348347
Brca subgroup196191
Hrr effector subgroup226230
All hrr348348
Completed00
Not completed348348
Withdrew: Ongoing231249
Withdrew: Death10684
Withdrew: Lost to follow-up20
Withdrew: Withdrawal by subject614
Withdrew: Regional crisis31

Outcome measures

PrimaryBreast Cancer Gene (BRCA) Subgroup: Radiographic Progression-free Survival (rPFS) Assessed by Investigator

rPFS: time interval from date of randomization to first date of radiographic progression as assessed by investigator or death due to any cause, whichever occurred first. rPFS was determined by: (1) progression of soft tissue lesions measured by computerized tomography (CT) or magnetic resonance imaging (MRI) per response evaluation criteria in solid tumors (RECIST) 1.1; (2) progression of bone lesions observed by bone scan per prostate cancer working group 3 (PCWG3) criteria: bone progression was confirmed by subsequent scan greater than or equal to (\>=) 6 weeks later. Week 8 scan was baseline to which all subsequent scans were compared to determine progression. A confirmatory scan with \>=2 new lesions indicated progression; A confirmatory scan not showing \>=2 new lesions means no progression. If Week 8 scan shows \<2 new bone lesions compared to baseline, first scan with \>=2 new lesions compared to Week 8 scan indicated progression, when confirmed by a subsequent scan \>=6 weeks later.

Time frame:
From date of randomization (Day -3 to Day 1) up to approximately 49 months
Reported as:
Median · months
Breast Cancer Gene (BRCA) Subgroup: Radiographic Progression-free Survival (rPFS) Assessed by Investigator
monthsBRCA Subgroup: Placebo With Abiraterone Acetate Plus PrednisoneBRCA Subgroup: Niraparib With Abiraterone Acetate Plus Prednisone
Breast Cancer Gene (BRCA) Subgroup: Radiographic Progression-free Survival (rPFS) Assessed by Investigator25.99 (22.11 to 41.17)NA (41.20 to NA)
Statistical analysis
  • BRCA Subgroup: Placebo With Abiraterone Acetate Plus Prednisone vs BRCA Subgroup: Niraparib With Abiraterone Acetate Plus Prednisone · Log Rank · p = <0.0001 (The priori threshold for statistical significance was 0.05.) · Hazard ratio (hr): 0.515 · 95% CI 0.370 to 0.717
PrimaryHRR Effector Subgroup: Radiographic Progression-free Survival (rPFS) Assessed by Investigator

rPFS: time interval from date of randomization to first date of radiographic progression as assessed by investigator or death due to any cause, whichever occurred first. rPFS was determined by: (1) progression of soft tissue lesions measured by CT or MRI per RECIST 1.1; (2) progression of bone lesions observed by bone scan per PCWG3 criteria: bone progression was confirmed by subsequent scan \>= 6 weeks later. Week 8 scan was baseline to which all subsequent scans were compared to determine progression. A confirmatory scan with \>=2 new lesions indicated progression; A confirmatory scan not showing \>=2 new lesions means no progression. If Week 8 scan shows \<2 new bone lesions compared to baseline, first scan with \>=2 new lesions compared to Week 8 scan indicated progression, when confirmed by a subsequent scan \>=6 weeks later.

Time frame:
From date of randomization (Day -3 to Day 1) up to approximately 49 months
Reported as:
Median · months
HRR Effector Subgroup: Radiographic Progression-free Survival (rPFS) Assessed by Investigator
monthsHRR Effector Subgroup: Placebo With Abiraterone Acetate Plus PrednisoneHRR Effector Subgroup: Niraparib With Abiraterone Acetate Plus Prednisone
HRR Effector Subgroup: Radiographic Progression-free Survival (rPFS) Assessed by Investigator27.56 (25.59 to NA)NA (41.20 to NA)
Statistical analysis
  • HRR Effector Subgroup: Placebo With Abiraterone Acetate Plus Prednisone vs HRR Effector Subgroup: Niraparib With Abiraterone Acetate Plus Prednisone · Log Rank · p = =0.0003 (The priori threshold for statistical significance was 0.025.) · Hazard ratio (hr): 0.571 · 95% CI 0.421 to 0.774
PrimaryAll HRR: Radiographic Progression-free Survival (rPFS) Assessed by Investigator

rPFS: time interval from date of randomization to first date of radiographic progression as assessed by investigator or death due to any cause, whichever occurred first. rPFS was determined by: (1) progression of soft tissue lesions measured by CT or MRI per RECIST 1.1; (2) progression of bone lesions observed by bone scan per PCWG3 criteria: bone progression was confirmed by subsequent scan \>= 6 weeks later. Week 8 scan was baseline to which all subsequent scans were compared to determine progression. A confirmatory scan with \>=2 new lesions indicated progression; A confirmatory scan not showing \>=2 new lesions means no progression. If Week 8 scan shows \<2 new bone lesions compared to baseline, first scan with \>=2 new lesions compared to Week 8 scan indicated progression, when confirmed by a subsequent scan \>=6 weeks later.

Time frame:
From date of randomization (Day -3 to Day 1) up to approximately 49 months
Reported as:
Median · months
All HRR: Radiographic Progression-free Survival (rPFS) Assessed by Investigator
monthsPlacebo With Abiraterone Acetate Plus PrednisoneNiraparib With Abiraterone Acetate Plus Prednisone
All HRR: Radiographic Progression-free Survival (rPFS) Assessed by Investigator29.54 (25.82 to NA)NA (41.20 to NA)
Statistical analysis
  • Placebo With Abiraterone Acetate Plus Prednisone vs Niraparib With Abiraterone Acetate Plus Prednisone · Log Rank · p = =0.0001 (The priori threshold for statistical significance was 0.02475.) · Hazard ratio (hr): 0.625 · 95% CI 0.490 to 0.799
SecondaryBRCA Subgroup: Time to Symptomatic Progression

Time to symptomatic progression was defined as time from the date of randomization to the date of any of the following (whichever occurred first): (a) the use of external beam radiation therapy for skeletal or pelvic symptoms, (b) the need for tumor-related orthopedic surgical intervention, (c) other cancer-related procedures (example: nephrostomy insertion, bladder catheter insertion, external beam radiation therapy, or surgery for tumor symptoms), (d) cancer-related morbid events (that is, fracture \[symptomatic and/or pathologic\], cord compression, urinary obstructive events), (e) initiation of a new systemic anti-cancer therapy because of cancer symptoms.

Time frame:
From date of randomization (Day -3 to Day 1) up to approximately 49 months
Reported as:
Median · months
BRCA Subgroup: Time to Symptomatic Progression
monthsBRCA Subgroup: Placebo With Abiraterone Acetate Plus PrednisoneBRCA Subgroup: Niraparib With Abiraterone Acetate Plus Prednisone
BRCA Subgroup: Time to Symptomatic ProgressionNA (39.72 to NA)NA (NA to NA)
Statistical analysis
  • BRCA Subgroup: Placebo With Abiraterone Acetate Plus Prednisone vs BRCA Subgroup: Niraparib With Abiraterone Acetate Plus Prednisone · Log Rank · p = =0.0001 (The priori threshold for statistical significance was 0.03426.) · Hazard ratio (hr): 0.444 · 95% CI 0.290 to 0.681
SecondaryHRR Effector Subgroup: Time to Symptomatic Progression

Time to symptomatic progression was defined as time from the date of randomization to the date of any of the following (whichever occurred first): (a) the use of external beam radiation therapy for skeletal or pelvic symptoms, (b) the need for tumor-related orthopedic surgical intervention, (c) other cancer-related procedures (example: nephrostomy insertion, bladder catheter insertion, external beam radiation therapy, or surgery for tumor symptoms), (d) cancer-related morbid events (that is, fracture \[symptomatic and/or pathologic\], cord compression, urinary obstructive events), (e) initiation of a new systemic anti-cancer therapy because of cancer symptoms.

Time frame:
From date of randomization (Day -3 to Day 1) up to approximately 49 months
Reported as:
Median · months
HRR Effector Subgroup: Time to Symptomatic Progression
monthsHRR Effector Subgroup: Placebo With Abiraterone Acetate Plus PrednisoneHRR Effector Subgroup: Niraparib With Abiraterone Acetate Plus Prednisone
HRR Effector Subgroup: Time to Symptomatic ProgressionNA (NA to NA)NA (41.40 to NA)
Statistical analysis
  • HRR Effector Subgroup: Placebo With Abiraterone Acetate Plus Prednisone vs HRR Effector Subgroup: Niraparib With Abiraterone Acetate Plus Prednisone · Log Rank · p = =0.0004 (The priori threshold for statistical significance was 0.02977.) · Hazard ratio (hr): 0.495 · 95% CI 0.332 to 0.738
SecondaryAll HRR: Time to Symptomatic Progression

Time to symptomatic progression was defined as time from the date of randomization to the date of any of the following (whichever occurred first): (a) the use of external beam radiation therapy for skeletal or pelvic symptoms, (b) the need for tumor-related orthopedic surgical intervention, (c) other cancer-related procedures (example: nephrostomy insertion, bladder catheter insertion, external beam radiation therapy, or surgery for tumor symptoms), (d) cancer-related morbid events (that is, fracture \[symptomatic and/or pathologic\], cord compression, urinary obstructive events), (e) initiation of a new systemic anti-cancer therapy because of cancer symptoms.

Time frame:
From date of randomization (Day -3 to Day 1) up to approximately 49 months
Reported as:
Median · months
All HRR: Time to Symptomatic Progression
monthsPlacebo With Abiraterone Acetate Plus PrednisoneNiraparib With Abiraterone Acetate Plus Prednisone
All HRR: Time to Symptomatic ProgressionNA (43.14 to NA)NA (NA to NA)
Statistical analysis
  • Placebo With Abiraterone Acetate Plus Prednisone vs Niraparib With Abiraterone Acetate Plus Prednisone · Log Rank · p = <0.0001 (The priori threshold for statistical significance was 0.03207.) · Hazard ratio (hr): 0.503 · 95% CI 0.364 to 0.695
SecondaryOverall Survival (OS)
Time frame:
From date of randomization (Day -3 to Day 1) up to 83 months

Results for this outcome have not been posted.

SecondaryTime to Subsequent Therapy
Time frame:
From date of randomization (Day -3 to Day 1) up to 83 months

Results for this outcome have not been posted.

SecondaryNumber of Participants With Treatment-emergent Serious Adverse Events
Time frame:
From Cycle 1 Day 1 up to 83 months

Results for this outcome have not been posted.

SecondaryNumber of Participants With Treatment-emergent Adverse Events by Severity
Time frame:
From Cycle 1 Day 1 up to 83 months

Results for this outcome have not been posted.

Adverse events

Collected over All cause mortality: From screening (Day -38 up to Day -1) up to approximately 49 months. Serious adverse events (SAEs) and other AEs: From Cycle 1 Day 1 up to approximately 49 months. Non-serious events are listed at a 5% frequency threshold.

Adverse event summary by group
GroupDeathsSeriousOther
Placebo With Abiraterone Acetate Plus Prednisone108/348 (31%)96/348 (27.6%)326/348 (93.7%)
Niraparib With Abiraterone Acetate Plus Prednisone85/348 (24.4%)136/347 (39.2%)338/347 (97.4%)
Most frequent serious events
Showing 10 of 181
Most frequent serious events
EventPlacebo With Abiraterone Acetate Plus PrednisoneNiraparib With Abiraterone Acetate Plus Prednisone
AnaemiaBlood and lymphatic system disorders4/34820/347
PneumoniaInfections and infestations10/34812/347
Urinary Tract InfectionInfections and infestations6/3489/347
HypokalaemiaMetabolism and nutrition disorders2/3488/347
Acute Kidney InjuryRenal and urinary disorders4/3486/347
SepsisInfections and infestations3/3485/347
HaematuriaRenal and urinary disorders5/3484/347
Cardiac FailureCardiac disorders2/3484/347
FallInjury, poisoning and procedural complications1/3484/347
Back PainMusculoskeletal and connective tissue disorders3/3484/347
Most frequent other events
Showing 10 of 46
Most frequent other events
EventPlacebo With Abiraterone Acetate Plus PrednisoneNiraparib With Abiraterone Acetate Plus Prednisone
AnaemiaBlood and lymphatic system disorders83/348178/347
HypertensionVascular disorders113/348152/347
ConstipationGastrointestinal disorders57/348122/347
NauseaGastrointestinal disorders50/348107/347
FatigueGeneral disorders64/34891/347
HypokalaemiaMetabolism and nutrition disorders69/34887/347
Back PainMusculoskeletal and connective tissue disorders76/34866/347
NeutropeniaBlood and lymphatic system disorders28/34874/347
ArthralgiaMusculoskeletal and connective tissue disorders74/34873/347
Covid-19Infections and infestations70/34862/347

Baseline characteristics

Age, Continuous
Age, Continuous(years)Placebo With Abiraterone Acetate Plus PrednisoneNiraparib With Abiraterone Acetate Plus PrednisoneTotal
Mean66.7 ± 8.8467.8 ± 8.7567.3 ± 8.81
Sex: Female, Male
Sex: Female, Male(Participants)Placebo With Abiraterone Acetate Plus PrednisoneNiraparib With Abiraterone Acetate Plus PrednisoneTotal
Female000
Male348348696
Ethnicity (NIH/OMB)
Ethnicity (NIH/OMB)(Participants)Placebo With Abiraterone Acetate Plus PrednisoneNiraparib With Abiraterone Acetate Plus PrednisoneTotal
Hispanic or Latino434083
Not Hispanic or Latino292287579
Unknown or Not Reported132134
Race (NIH/OMB)
Race (NIH/OMB)(Participants)Placebo With Abiraterone Acetate Plus PrednisoneNiraparib With Abiraterone Acetate Plus PrednisoneTotal
American Indian or Alaska Native314
Asian6777144
Native Hawaiian or Other Pacific Islander101
Black or African American101828
White257246503
More than one race224
Unknown or Not Reported8412
Age, Categorical
Age, Categorical(Participants)Placebo With Abiraterone Acetate Plus PrednisoneNiraparib With Abiraterone Acetate Plus PrednisoneTotal
Adults (18-64 years)135116251
From 65 to 84 years212227439
85 years and over156
Region of Enrollment
Region of Enrollment(Participants)Placebo With Abiraterone Acetate Plus PrednisoneNiraparib With Abiraterone Acetate Plus PrednisoneTotal
ARGENTINA151530
AUSTRALIA91423
BELARUS617
BELGIUM459
BRAZIL302858
BULGARIA325
CANADA141529
CHINA242953
CZECH REPUBLIC336
DENMARK6410
FRANCE171532
GERMANY6612
HUNGARY437
ISRAEL31114
ITALY322456
MALAYSIA41115
MEXICO314
NETHERLANDS213
NEW ZEALAND639
POLAND121325
PORTUGAL112
RUSSIAN FEDERATION11920
SOUTH AFRICA123
SOUTH KOREA201939
SPAIN182139
SWEDEN235
TAIWAN111021
THAILAND437
TURKEY242145
UKRAINE121426
UNITED KINGDOM111122
UNITED STATES303060
08

Study locations

387 sites

Showing the first 100 of 387 sites across 33 countries. Choose a country and city above to see the rest.

09

References and documents

Publications

  • Attard G, Agarwal N, Graff JN, Sandhu S, Efstathiou E, Ozguroglu M, Pereira de Santana Gomes AJ, Vianna K, Luo H, Gotto GT, Cheng HH, Kim W, Varela CR, Schaeffer D, Kramer K, Li S, Baron B, Shen F, Mundle SD, McCarthy SA, Olmos D, Chi KN, Rathkopf DE. Niraparib and abiraterone acetate plus prednisone for HRR-deficient metastatic castration-sensitive prostate cancer: a randomized phase 3 trial. Nat Med. 2025 Dec;31(12):4109-4118. doi: 10.1038/s41591-025-03961-8. Epub 2025 Oct 7. PubMed 41057655 ↗

Study documents

PDFs hosted by the registry, ClinicalTrials.gov.

Individual participant data

Plan to share: Yes — The data sharing policy of Johnson \& Johnson Innovative Medicine is available at innovativemedicine.jnj.com/our-innovation/clinical-trials/transparency. As noted on this site, requests for access to the study data can be submitted through Yale Open Data Access (YODA) Project site at yoda.yale.edu

Data sharing details ↗ · www.jnj.com

10

Timeline

2 registry updates since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reachedSimilar studies: half by the dot; the band is the middle halfHalf of similar studies reached it by the dot; the band is the middle half, from a quarter to three quarters

Ran from Sep 2020 to primary completion in Jan 2025, 51 months.

Results were first posted in Jan 2026, 1 year after primary completion.

Of 126 industry-sponsored phase 3 interventional studies under Prostatic Neoplasms, half reached primary completion within 38 months of starting (the median), counting those still running; a quarter within 23 and three quarters within 53. This study's 51 months is above that.

Counting every sponsor, half of 265 studies reached it within 57 months; a quarter within 31 and three quarters within 100.

How these figures are worked out, and which studies are left out of them.

Registered
Jul 31, 2020
First posted
Aug 4, 2020
StartActual
Sep 23, 2020
Primary completionActual
Jan 7, 2025
CompletionEst.
Nov 1, 2027
Results first posted
Jan 22, 2026
Last update
Nov 4, 2026
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
Minor edits
Nothing that changes what the study is or who can join. Edited: verification date and site details
2 updates, last Nov 4, 2026
Show all 2 updates
  1. Nov 4, 2026
    Minor edits only
    + 2 other changes: verification date and site details
  2. Sep 28, 2026
    Minor edits only
    + 1 other change: verification date

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 ↗

11

Registry details

Key details

Study ID
NCT04497844
Lead sponsor
Janssen Research & Development, LLC
Responsible party
Sponsor
First posted
Aug 4, 2020
Start date
Sep 23, 2020
Primary completion
Jan 7, 2025
Completion
Nov 1, 2027 (estimated)
Results posted
Jan 22, 2026
Last update
Nov 4, 2026

Study contacts

Janssen Research & Development, LLC Clinical Trial
study director · Janssen Research & Development, LLC

Oversight

Data monitoring committee
Yes
FDA-regulated drug
Yes
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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Studies of the drugs tested here: Niraparib · Abiraterone Acetate

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