Novel ACK1 Inhibitor (R)-9b in Patients With Prostate Cancer

Summary

TITLE: Phase 1 First in Human Trial to Assess Safety and Tolerability of the Novel ACK1 Inhibitor (R)-9bMS in Patients with Prostate Cancer (PHAROS)

STUDY DESCRIPTION: Prostate cancer (PC) patients receive androgen deprivation therapy (ADT), but recalcitrant disease recurs typically within 2-3 years, referred to as the Castration Resistant Prostate Cancer (CRPC). Androgen receptor (AR) targeted therapies, such as Enzalutamide (Enz) or Abiraterone (Abi), are FDA-approved therapeutics for CRPC patients. However, virtually all patients develop resistance.

A non-receptor tyrosine kinase, ACK1 act as a novel epigenetic modifier in prostate tumors, regulating AR and its splice variant, AR-V7 expression. A new class of ACK1 small molecule inhibitor, (R)-9bMS, was developed that exhibited excellent drug-like properties. Treatment with (R)-9bMS suppressed Abi and Enz-resistant tumor growth in mice. Robust immune activation against prostate tumors was also reflected in mice treated with ACK1 inhibitor, (R)-9bMS. Importantly (R)-9bMS functionally reinvigorated peripheral blood mononuclear cells (PBMCs) of CRPC patients to mount a robust immune response against CRPC organoids. Collectively, these data indicate that the ACK1 inhibitor, (R)-9bMS, fulfills a unique niche, wherein it not only suppressed AR/AR-V7 within the tumor milieu, but also activated host immune system by overcoming CSK-restrained LCK activity, to mount a robust 'dual' anti-tumor response.

OBJECTIVES: Primary Objective: To assess the safety and tolerability of (R)-9bMS in patients with metastatic castration-resistant prostate cancer.

Secondary Objectives: To determine the maximum tolerated dose (MTD) and recommended phase 2 dose (RP2D) of (R)-9bMS in patients with CRPC. To determine the pharmacokinetics (PK) of (R)-9bMS in patients after single and multiple dose oral administration. To assess clinical outcomes and anti-tumor activity in patients treated with (R)-9bMS.

ENDPOINTS: Primary Endpoint: Frequency of dose-limiting toxicities and toxicity and severe AEs per CTCAE v 5.0.

Secondary Endpoints:

* RP2D (recommended phase 2 dose)
* PK (pharmacokinetics)
* PSA responses
* Duration of responses
* ORR (objective response rate)
* OS (overall survival)
* PFS (progression free survival)
* DSS (disease specific survival)
* Toxicity and severe AEs per CTCAE v 5.0 STUDY POPULATION: Approximately 18-30 adult patients with a histologic or cytologic diagnosis of metastatic castration resistant prostate cancer will be enrolled.

PHASE: Phase I

DESCRIPTION OF SITES: This study will be open to enrollment at the University of Wisconsin Carbone Cancer Center

DESCRIPTION OF STUDY INERVENTION: (R)-9bMS will be taken by mouth twice daily until completion of 12 cycles, progression or intolerance

STUDY DURATION: 12 months for enrollment + 12 months treatment + 12 months follow-up + 12 months for data analysis = 48 months.

Conditions

• Metastatic Castration-resistant Prostate Cancer (CRPC)
• Metastatic Castration-resistant Prostate Carcinoma

Interventions

DRUG

(R)-9bMS

(R)-9bMS will be given in clinic on day 1, two doses 12 hours (+/- 30 minutes) apart, and on day 2, 12 hours (+/- 30 minutes) after the second day 1 dose. Patients will be admitted overnight for these first 3 doses. Patient must be fasting 1 hour before and 1 hour after doses for these first 3 doses. (R)-9bMS should be taken with a glass of water. Patients will be dispensed home supply after C1D2 morning dose.

Sponsors & Collaborators

• National Cancer Institute (NCI)

  collaborator NIH

• Washington University School of Medicine

  collaborator OTHER

• University of Wisconsin, Madison

  collaborator OTHER

• TechnoGenesys, Inc.

  lead INDUSTRY

Principal Investigators

• Douglas McNeel, MD, PhD · University of Wisconsin, Madison

Study Design

Allocation

NON_RANDOMIZED

Purpose

TREATMENT

Masking

NONE

Model

SEQUENTIAL

Eligibility

Min Age

18 Years

Sex

MALE

Healthy Volunteers

No

Timeline & Regulatory

Start

2026-03-13

Primary Completion

2027-12-30

Completion

2028-03-30

FDA Drug

Yes

Countries

• United States

Study Locations