Pacritinib in Participants With Metastatic Castrate-Resistant Prostate Cancer That Progressed on or After Prior Treatment With Androgen Receptor Signaling Inhibitors

NCT07226713 | Not Yet Recruiting Phase 2 DMC FDA Drug

• 1 other identifier: IIT-KILARI-POSTPONE
• Study Type: interventional
• Target: 32
• Locations: 1 country
• Sites: 1

Brief Summary

This is a single-arm, open-label phase 2 study to evaluate the role of pacritinib for patients with metastatic castrate-resistant prostate cancer that have progressed on ARSI. Patients will receive pacritinib 200 mg twice daily. To be eligible, patients must have a biopsy of a metastatic site within 30 days of treatment that demonstrates positive STAT5 activation status

Conditions

Prostate Cancer

Outcome Measures

Primary Outcomes (1)

• Progression-free Survival

  Six-month radiographic progression-free survival is defined as the probability that a given subject will be alive and free from radiographic progression per Prostate Cancer Working Group 3 guidelines at 24 weeks.

  Six months

Study Arms (1)

Pacritinib

EXPERIMENTAL

Pacritinib is an oral drug.

Drug: Pacritinib

Interventions

Pacritinib DRUG

Pacritinib is an oral drug which will be taken daily at a dose of 200 mg twice a day (BID).

Also known as: SB1518

Pacritinib

Eligibility Criteria

• Age: 18 Years+
• Sex: male
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• I. To be eligible for screening:
• Patients aged ≥ 18 years.
• Histologically or cytologically confirmed prostate adenocarcinoma.
• Have current evidence of metastatic disease documented by either bone scan, CT/MRI and/or PSMA PET scan
• Have disease that progressed while receiving androgen deprivation therapy (ADT) (or post bilateral orchiectomy) and during or after treatment with at least one androgen receptor signaling inhibitor (ARSI) (e.g., abiraterone acetate, enzalutamide, apalutamide, darolutamide) for metastatic hormone-sensitive prostate cancer (HSPC) (mHSPC or nmHSPC) or mCRPC.
• a. Note: Participants may have received abiraterone acetate and docetaxel or darolutamide and docetaxel for HSPC. However, participants must have received no more than 6 cycles of docetaxel and had no radiographic disease progression while receiving docetaxel. Disease progression could be prostate-specific antigen (PSA) based or radiographic progression per Prostate Cancer Working Group 3 (PCWG3) guidelines.
• Screening serum testosterone \< 50 ng/dL.
• Eastern Cooperative Oncology Group (ECOG), Performance Status grade 0-1 or Karnofsky Performance Status ≥ 70
• No prior janus kinase2 (JAK2) inhibitor treatment.
• Left ventricular cardiac ejection fraction of ≥ 50% by echocardiogram or multigated acquisition (MUGA) scan.
• Adequate organ function as defined by the following laboratory values at screening:
• Serum aspartate transaminase (AST), serum glutamic oxaloacetic transaminase (SGOT), serum alanine transaminase (ALT) and serum glutamic pyruvic transaminase (SGPT) \< 2.5 x upper limit of normal (ULN).
• Total serum bilirubin ≤ 1.5 x ULN. In subjects with Gilbert's syndrome, if total bilirubin is \>1.5 × ULN, measure direct and indirect bilirubin and if direct bilirubin is ≤ 1.5 × ULN, the subject may be eligible).
• Serum potassium ≥ 3.5 mmol/L. Supplementation and re-screening is allowed.
• Estimated glomerular filtration rate (GFR) \> 45 ml/min using the Cockroft-Gault equation.

You may not qualify if:

• Patient does not have positive STAT5 activation status in PC core biopsies.
• Previously treated with pacritinib.
• Use of investigational agents within 28 days prior to randomization.
• Use of other prohibited medications within seven days prior to Cycle 1, Day 1 or 5x half-life of the drug, whichever is longer.
• Systemic treatment with a strong CYP3A4 inhibitor or inducer within 14 days prior to the start of treatment.
• Uncontrolled hypertension.
• Baseline severe hepatic impairment (Child-Pugh Class B \& C).
• An intercurrent illness that is not controlled, such as active infection, psychiatric illness, or social situations that would limit compliance with study requirements.
• Any chronic medical condition requiring a higher dose of corticosteroid than an equivalent of 10 mg prednisone/prednisolone per day.
• Significant recent bleeding history, as defined as National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE) v5.0 Grade ≥ 2 within three months prior to start of treatment, unless precipitated by an inciting event (e.g., surgery, trauma, or injury).
• Systemic treatment with medications that increase the risk of bleeding, including anticoagulants (warfarin, direct oral anticoagulant, etc.), antiplatelet agents (except for aspirin dosages of ≤ 100 mg/day), anti-vascular endothelial growth factor (anti-VEGF) agents, and daily use of COX-1 inhibiting nonsteroidal anti-inflammatory agents (NSAIDs) within 14 days prior to the start of treatment.
• Systemic treatment with medications that can prolong the QT interval within 14 days prior to the start of treatment. Shorter washout periods may be permitted with the approval of the PI, provided that the washout period is at least five half-lives of the drug prior to the start of treatment.
• QT corrected for heart rate by Fridericia's cube root formula (QTcF) prolongation \> 450 ms or other factors that increase the risk for QT interval prolongation (e.g., heart failure, hypokalemia \[defined as serum potassium \< 3.0 mEq/L that is persistent and refractory to correction\]), or history of long QT interval syndrome.
• New York Heart Association Class II, III, or IV congestive heart failure.
• Any active gastrointestinal or metabolic condition that could interfere with absorption of oral medication.

Sponsors & Collaborators

• Medical College of Wisconsin: lead

Study Sites (1)

Froedtert & the Medical College of Wisconsin

Milwaukee, Wisconsin, 53226, United States

Location

MeSH Terms

Conditions

Prostatic Neoplasms

Interventions

11-(2-pyrrolidin-1-ylethoxy)-14,19-dioxa-5,7,26-triazatetracyclo(19.3.1.1(2,6).1(8,12))heptacosa-1(25),2(26),3,5,8,10,12(27),16,21,23-decaene

Condition Hierarchy (Ancestors)

Genital Neoplasms, Male; Urogenital Neoplasms; Neoplasms by Site; Neoplasms; Genital Diseases, Male; Genital Diseases; Urogenital Diseases; Prostatic Diseases; Male Urogenital Diseases

Study Officials

• Deepak Kilari, MD

  Medical College of Wisconsin

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Medical College of Wisconsin Cancer Center Clinical Trials Office

CONTACT

866-680-0505; cccto@mcw.edu

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor

Study Record Dates

• First Submitted: November 6, 2025
• First Posted: November 10, 2025
• Study Start (Estimated): July 1, 2026
• Primary Completion (Estimated): March 1, 2029
• Study Completion (Estimated): March 1, 2031
• Last Updated: May 4, 2026

Record last verified: 2026-04

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)