Exploratory PK and Imaging Study of PSMA-Targeted Trillium Compounds and PTI-122 in Metastatic Prostate Cancer

A Phase 0 Study of the Pharmacokinetics and Biodistribution of PSMA-Targeted [In-111]-Labeled Trillium Compounds With and Without PTI-122 in Patients With Metastatic Prostate Cancer to Inform Future Phase 1 Dosing With [Ac-225]-Trillium-PSMA Radionuclide Therapy

Exploratory study in adult males with metastatic prostate cancer intended to characterize the pharmacokinetics and biodistribution of PSMA-Targeted [In-111]-Labeled Trillium Compounds with and without the cytoprotective agent PTI-122. Up to 36 eligible subjects will be enrolled. Additional subjects may be enrolled if there is insufficient data for evaluation, for example if the original study subjects do not complete required imaging studies for reasons unrelated to adverse events.

Up to four PSMA-Targeted [In-111]-Labeled Trillium Compounds will be evaluated. Each compound will be evaluated first without the cytoprotective agent, PTI-122, then the [In-111]-labeled Trillium Compound may be co-administered with PTI-122.

Study Overview

• Status: Completed
• Conditions: Prostate Cancer
• Intervention / Treatment: Drug: PSMA-Targeted [In-111]-Labeled Trillium Compound; Drug: PTI-122

• Study Type: Interventional
• Enrollment (Actual): 23
• Phase: Early Phase 1

Contacts and Locations

Study Locations

• United States
  • Florida
    • Miami, Florida, United States, 33165
      • Biogenix Molecular
  • Maryland
    • Glen Burnie, Maryland, United States, 21061
      • Advanced Molecular Imaging & Therapy
  • Nebraska
    • Omaha, Nebraska, United States, 68130
      • XCancer Omaha/Urology Cancer Center
  • Tennessee
    • Knoxville, Tennessee, United States, 37920
      • University of Tennessee Medical Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Adult males with metastatic prostate cancer
• ECOG performance score 0-2
• Stable androgen deprivation or other hormone therapy (30 days) or therapy planned but not yet initiated

• PSMA PET scan between 3 and 28 days prior to radiotracer injection with at least 2 PSMA positive lesions and either:

  1. One soft tissue lesion measuring ≥ 15 mm in the longest diameter with SUVmax lesion ≥ SUVmean normal liver, OR
  2. Two bone lesions measuring ≥ 15 mm in the longest diameter with SUVmax lesion ≥ 2 x SUVmax normal liver
• Able to understand and adhere to study requirements, and voluntarily give informed consent

Exclusion Criteria:

• No other malignancy undergoing treatment
• No PSMA-targeted therapy ongoing
• Inability or unwillingness to undergo SPECT/CT imaging
• Serum creatinine > 1.5 mg/dL or creatinine clearance ≤50 mL/min by Cockcroft-Gault estimation
• Concurrent participation in the active treatment phase of another clinical trial of investigational medicinal product(s)
• Significant intercurrent illness, treatment-related toxicity, or psychiatric illness/social situation that could place the subject at undue risk during study participation, significantly alter study outcomes, or affect subject compliance with study requirements for dosing and evaluation, as determined by the investigator

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Non-Randomized
• Interventional Model: Sequential Assignment
• Masking: None (Open Label)

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Trillium Compound Alone; Single dose of PSMA-Targeted [In-111]-Labeled Trillium Compound	Drug: PSMA-Targeted [In-111]-Labeled Trillium Compound; Radiotracer
Experimental: Trillium Compound + Single Dose PTI-122; Single dose of PSMA-Targeted [In-111]-Labeled Trillium Compound plus single dose of PTI-122 at 5, 10 or 15 mg	Drug: PSMA-Targeted [In-111]-Labeled Trillium Compound; Radiotracer; Drug: PTI-122; Cytoprotective agent
Experimental: Trillium Compound + Multiple Dose PTI-122; Single dose of PSMA-Targeted [In-111]-Labeled Trillium Compound plus two doses of PTI-122 at the preferred dose level	Drug: PSMA-Targeted [In-111]-Labeled Trillium Compound; Radiotracer; Drug: PTI-122; Cytoprotective agent

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Amount of radiotracer absorbed by tumor	Tumor uptake measured on imaging	Over 168 hours post-injection
Amount of radioactivity in blood	Radioactivity measured pre- and post-radiotracer injection	Over 168 hours post-injection
Amount of radiotracer absorbed by organs	Organ uptake measured on imaging	Over 168 hours post-injection

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Amount of PTI-122 in blood	PTI-122 measured pre- and post-dose	Over 168 hours post-injection
Incidence of adverse events	Occurrence of adverse events during the study	Over 168 hours post-injection

Collaborators and Investigators

• Sponsor: Ratio Therapeutics, Inc.
• Investigators: Study Director: John Babich, PhD, Ratio Therapeutics, Inc.

Study record dates

Study Major Dates

• Study Start (Actual): December 8, 2022
• Primary Completion (Actual): December 12, 2023
• Study Completion (Actual): December 12, 2023

Study Registration Dates

• First Submitted: February 23, 2023
• First Submitted That Met QC Criteria: March 15, 2023
• First Posted (Actual): March 17, 2023

Study Record Updates

• Last Update Posted (Estimated): December 13, 2023
• Last Update Submitted That Met QC Criteria: December 12, 2023
• Last Verified: December 1, 2023

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Neoplasms; Urogenital Neoplasms; Neoplasms by Site; Genital Neoplasms, Male; Prostatic Diseases; Urogenital Diseases; Male Urogenital Diseases; Genital Diseases, Male; Genital Diseases; Prostatic Neoplasms
• Other Study ID Numbers: RTX-PSMA-P101

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No