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FPI-2265 (225Ac-PSMA-I&T) for Patients With PSMA-Positive Metastatic Castration-Resistant Prostate Cancer (mCRPC)

Phase 2
Recruiting
Conditions
Metastatic Castration-resistant Prostate Cancer
Interventions
Registration Number
NCT06402331
Lead Sponsor
Fusion Pharmaceuticals Inc.
Brief Summary

This is an open-label, randomized, multicenter study of FPI-2265 (225Ac-PSMA-I\&T). Patient population is adult participants with PSMA positive mCRPC who have had previous treatment with with 177Lu-PSMA-617 or another 177Lu-PSMA radioconjugate (RC). The purpose of the study is to determine the safety and tolerability, and recommended dose and regiment of FPI-2265.

Detailed Description

This is an open-label, randomized, multicenter study of FPI-2265 (225Ac-PSMA-I\&T). The purpose of the dose optimization segment (Phase 2) is to determine the recommended FPI-2265 dose and regimen. Conclusions from Phase 2 will be based on safety, tolerability, and anti-tumor activity.

Screening Period: At screening, participants will be assessed for eligibility and undergo a positron emission tomography (PET)/computed tomography (CT) scan to evaluate PSMA positivity. Only participants with PSMA positive cancer and confirmed eligibility criteria will be randomized.

Participants randomized will enter the treatment period and receive investigational doses of FPI2265 according to the dose level and schedule as specified per proposed dose arm.

Part A participants will enroll 1:1:1 at three dose level/schedules, to arms 1, 2 or 3

Part B participants will enroll after completion of part A, in a 1:1 randomization scheme to arms 6 or 7.

Once Part A is fully enrolled and participants have been followed for at least 12 weeks, data from Arm 1 and 2 will be analyzed to assess the the feasibility of enrolling participants to arms 4 and 5.

All participants will be monitored and assessed for efficacy response, disease progression and adverse events.

Supportive care will be allowed in all arms at the discretion of the investigator and includes available care for the eligible participant according to best institutional practice for mCRPC treatment, including androgen deprivation therapy (ADT).

Follow-up after end of treatment visit will proceed for 5 years.

5 participants will be enrolled into a dosimetry substudy (open at select sites only). Dosimetry substudy participants will be administered one dose at of FPI2265 and proceed with dosimetric assessments will be taken at a number of timepoints after dose administration.

Recruitment & Eligibility

Status
RECRUITING
Sex
Male
Target Recruitment
100
Inclusion Criteria
  • Phase 2: Eastern Cooperative Oncology Group (ECOG) Performance Status 0 or 1
  • Diagnosis of adenocarcinoma of prostate proven by histopathology.
  • Must have had prior orchiectomy and/or ongoing androgen-deprivation therapy and a castrate level of serum/plasma testosterone
  • Progressive mCRPC at time of study entry.
  • Must have been previously treated with lutetium-PSMA therapy (lutetium-177 vipivotide tetraxetan or other lutetium-177-PSMA RLT). Treatment must have been completed >6 weeks prior to the first dose of study drug.
  • Participants with known BRCA mutations should have received FDA-approved therapies such as PARP inhibitors, per Investigator discretion.
  • Positive PSMA PET/CT scan
  • Adequate organ function
  • For participants who have partners of childbearing potential: Partner and/or participant must not be planning to conceive and must use a method of birth control with adequate barrier protection deemed acceptable by the Principal Investigator during the study treatment and for six months after last study drug administration.

Key

Exclusion Criteria
  • Participants who received more than two prior lines of cytotoxic chemotherapy for CRPC.
  • Phase 2: participants who progress prior to administration of the 3rd cycle of prior treatment with 177Lu-PSMA therapy
  • All prior treatment-related adverse events must have resolved to Grade ≤1 (CTCAE v5.0). Alopecia and stable persistent Grade 2 peripheral neuropathy may be allowed at the discretion of the Investigator.
  • Participants with known, unresolved, urinary tract obstruction are excluded.
  • Administration of any systemic cytotoxic or investigational therapy ≤30 days of the first dose of study treatment or five half-lives, whichever is shorter. Completion of large-field external beam radiotherapy ≤four weeks of the first dose of study treatment.
  • Participants with a history of central nervous system (CNS) metastases are excluded except those who have received therapy
  • Participants with any liver metastases will be excluded from the Phase 2 segment of the study.
  • Participants with skeletal metastases presented as a superscan on a ⁹⁹ᵐTc bone scan.
  • Previous or concurrent cancer that is distinct from the cancer under investigation in primary site or histology, except treated cutaneous basal cell carcinoma or squamous cell carcinoma and superficial bladder tumors. Any cancer curatively treated >two years prior to the first dose of treatment is permitted.
  • Concurrent serious (as determined by the investigator) medical conditions
  • Major surgery ≤30 days prior to the first dose of study treatment.

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Part A Arm 1FPI-2265-
Part A Arm 2FPI-2265-
Part A Arm 3FPI-2265-
Part B Arm 7FPI-2265-
Part B Arm 4FPI-2265to be utilized based on analysis of Part A
Part B Arm 5FPI-2265to be utilized based on analysis of Part A
Part B Arm 6FPI-2265-
Primary Outcome Measures
NameTimeMethod
Frequency, duration, and severity of treatment-emergent adverse events (TEAEs)From first dose until end of long-term follow-up, 5 years from end of treatment visit.

Frequencies and percentages of participants with TEAEs will be summarized. Analysis will also be completed regarding duration of TEAEs and their severity.

Frequency and proportion of participants with PSA50 responseFrom first dose until 12 weeks after the first administered dose of FPI-2265.

PSA50 response is defined as a decline in PSA levels by at least 50% and is used to evaluate anti-tumor activity.

Secondary Outcome Measures
NameTimeMethod

Trial Locations

Locations (18)

City of Hope Comprehensive Cancer Center

🇺🇸

Duarte, California, United States

Hoag Health Center Irvine

🇺🇸

Irvine, California, United States

VA Greater Los Angeles Healthcare System

🇺🇸

Los Angeles, California, United States

University of California Los Angeles

🇺🇸

Los Angeles, California, United States

UCSF School of Medicine

🇺🇸

San Francisco, California, United States

Biogenix Molecular, LLC

🇺🇸

Miami, Florida, United States

University of Iowa Hospitals and Clinics

🇺🇸

Iowa City, Iowa, United States

United Theranostics

🇺🇸

Glen Burnie, Maryland, United States

BAMF Health

🇺🇸

Grand Rapids, Michigan, United States

SSM Health Saint Louis University Hospital

🇺🇸

Saint Louis, Missouri, United States

XCancer

🇺🇸

Omaha, Nebraska, United States

New Mexico Oncology Hematology Consultants Ltd.

🇺🇸

Albuquerque, New Mexico, United States

Laura and Isaac Perlmutter Cancer Center at NYU Langone

🇺🇸

New York, New York, United States

Memorial Sloan Kettering Cancer Center - NYC

🇺🇸

New York, New York, United States

Oregon Health and Science University (OHSU, Knight Cancer Center)

🇺🇸

Portland, Oregon, United States

VA North Texas Health Care System, Nuclear Medicine Service

🇺🇸

Dallas, Texas, United States

The University of Texas Southwestern Medical Center

🇺🇸

Dallas, Texas, United States

U.T. MD Anderson Cancer Center

🇺🇸

Houston, Texas, United States

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