A Phase 1 interventional study of INR731 and Enzalutamide in Metastatic Castration-resistant Prostate Cancer (mCRPC), sponsored by Novartis Pharmaceuticals. Recruiting at 13 sites in 8 countries. Open to male participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-10-23.
Sponsored by Novartis Pharmaceuticals (part of Novartis) · Phase 1, Interventional, and Treatment
The purpose of this study is to assess the safety, tolerability, pharmacokinetics/pharmacodynamics, preliminary anti-tumor activity, and recommended dose of INR731 as a single agent and in combination with standard-of-care androgen receptor pathway inhibitors (ARPIs) in adult patients with metastatic prostate cancer.
This is a first-in-human, open-label, phase I, multi-center study which consists of three treatment arms: INR731 single agent (Arm A), and INR731 in combination with enzalutamide (Arm B) or abiraterone (Arm C).
The single agent arm has a dose escalation part followed by a dose expansion part. Once the single agent recommended dose(s) is determined during dose escalation, the study may proceed to dose expansion to further explore safety, tolerability and preliminary anti-tumor activity. The single agent dose expansion part will include a post-standard of care (SOC) metastatic castration resistant prostate cancer (mCRPC) group and patients with time to castration resistance (TTCR) \<12 months.
The combination arms have a dose escalation of INR731 in combination with enzalutamide or abiraterone followed by a dose expansion of INR731 in combination with enzalutamide only. The combination dose escalation will be conducted in patients with mCRPC who have progressed following standard of care (post-SOC). During combination escalation, once the safety and tolerability of INR731 with the combination agent(s) is assessed, the study may proceed to dose expansion. The combination dose expansion part will include first-line (1L) mCRPC patients with no prior treatment in the mCRPC setting.
7,046 studies on the registry are indexed under Prostatic Neoplasms; 1,580 are open to participants now.
This study's planned enrollment of 208 is above the median of 60 across 5,348 interventional studies indexed under Prostatic Neoplasms.
Browse Prostatic Neoplasms studies →Novartis Pharmaceuticals is the lead sponsor of 2,718 studies on the registry; 221 are open to participants now.
Of its 585 completed or terminated interventional studies of FDA-regulated products, 438 (75%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Other protocol-defined inclusion/exclusion criteria may apply.
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
ECOG performance status
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Metastases
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
QT and QTc
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The dose escalation part with single agent INR731 may be followed by a dose expansion part.
Drug: INR731 · Drug: Androgen deprivation therapy (ADT)
The dose escalation part with INR731 in combination with enzalutamide may be followed by a dose expansion part.
Drug: INR731 · Drug: Enzalutamide · Drug: Androgen deprivation therapy (ADT)
Dose escalation of INR731 in combination with abiraterone.
Drug: INR731 · Drug: Abiraterone · Drug: Androgen deprivation therapy (ADT)
Oral administration
Oral administration
Oral administration
Background therapy. Patients will continue receiving ADT throughout this clinical study as part of the standard of care.
Incidence and severity of dose-limiting toxicities (DLTs)
A DLT is defined as an adverse event or abnormal laboratory value of Common Terminology Criteria for Adverse Events (CTCAE) grade ≥ 3 that occurs within the first 28 days and not clearly and incontrovertibly assessed as due to disease progression, intercurrent illness, concomitant medication, or extraneous causes with the exceptions defined in the study protocol. Other clinically significant toxicities may be considered to be DLTs, even if not CTCAE grade 3 or higher.
Time frame: 28 days
Incidence and severity of Adverse Events (AEs) and Serious Adverse Events (SAEs)
Incidence and severity of AEs and SAEs, including changes in laboratory values, vital signs and electrocardiograms (ECGs) qualifying and reported as AEs.
Time frame: Up to approximately 24 months
Frequency of dose interruptions and reductions
Number of participants with dose interruptions and/or reductions to assess the tolerability.
Time frame: Up to approximately 24 months
Dose intensity
Dose intensity defined as the ratio of actual cumulative dose received and actual duration of exposure.
Time frame: Up to approximately 24 months
Overall Response Rate (ORR)
ORR is defined as proportion of patients achieving a confirmed complete response (CR) or partial response (PR) per Prostate Cancer Working Group 3 (PCWG3)-modified Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST v1.1) as assessed by the investigator.
Time frame: Up to approximately 24 months
Disease Control Rate (DCR)
DCR is defined as proportion of patients achieving a CR, PR or stable disease (SD) per PCWG3-modified RECIST v1.1 as assessed by the investigator.
Time frame: Up to approximately 24 months
Radiological Progression Free Survival (rPFS)
rPFS is defined as the time from the date of start of treatment to the date of the first documented radiological progression according to PCWG3-modified RECIST v1.1 or death due to any cause.
Time frame: Up to approximately 24 months
Prostate-Specific Antigen 50% response rate (PSA50 rate)
PSA50 rate is defined as the proportion of patients who achieve a ≥50% decrease in prostate-specific antigen (PSA) from baseline at any timepoint, confirmed by a second PSA measurement ≥3 weeks later without any PSA progression in between.
Time frame: Up to approximately 24 months
Area under the plasma concentration-time curve (AUC) of INR731
Pharmacokinetic (PK) parameters based on plasma concentrations of INR731.
Time frame: From pre-dose up to 24 hours after dosing on Cycle 1 Day 1 and Day 15. One cycle = 28 days.
Maximum plasma concentration (Cmax) of INR731
PK parameters based on plasma concentrations of INR731.
Time frame: From pre-dose up to 24 hours after dosing on Cycle 1 Day 1 and Day 15. One cycle = 28 days.
Time to reach maximum plasma concentration (Tmax) of INR731
PK parameters based on plasma concentrations of INR731.
Time frame: From pre-dose up to 24 hours after dosing on Cycle 1 Day 1 and Day 15. One cycle = 28 days.
Trough concentration (Ctrough) of INR731
PK parameters based on plasma concentrations of INR731.
Time frame: From pre-dose up to 24 hours after dosing on Cycle 1 Day 1 and Day 15. One cycle = 28 days.
Plasma concentrations of study drugs
Concentration versus time profiles of study drugs.
Time frame: From pre-dose up to 24 hours after dosing on Cycle 1 Day 1 and Day 15. One cycle = 28 days.
Progression Free Survival (PFS)
PFS is defined as time from date of start of treatment to the first documented progression (radiological, clinical, or PSA progression) or death from any cause, whichever occurs first.
Time frame: Up to approximately 24 months
Plan to share: No — Novartis is committed to sharing with qualified external researchers, access to patient-level data and supporting clinical documents from eligible studies. These requests are reviewed and approved by an independent review panel on the basis of scientific merit. All data provided is anonymized to respect the privacy of patients who have participated in the trial in line with applicable laws and regulations. This trial data availability is according to the criteria and process described on www.clinicalstudydatarequest.com.
No publications or documents are linked to this record.
Started May 2026 (actual). Primary completion is estimated for Jun 2030, 48 months after the start.
Of 212 industry-sponsored phase 1 interventional studies under Prostatic Neoplasms, half reached primary completion within 37 months of starting (the median), counting those still running; a quarter within 20 and three quarters within 62. This study's planned 48 months is above that.
Counting every sponsor, half of 455 studies reached it within 43 months; a quarter within 23 and three quarters within 68.
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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