The Present Study Aims to Compare Patients Who Receive the Investigational Product (177Lu-DOTA-rosopatamab) Plus Standard of Care, in Comparison to Standard of Care Only

NCT04876651 | Terminated Phase 3 DMC

• 1 other identifier: 177Lu-TLX591-002
• Study Type: interventional
• Target: 16
• Locations: 2 countries
• Sites: 6

Brief Summary

This multinational, multicenter, prospective, randomized, controlled, open label Phase 3 study is designed to investigate and confirm the benefits and risks associated with the PSMA-targeted antibody, 177Lu DOTA rosopatamab administered together with Standard of Care (SoC), as compared to the best SoC alone. The phase 3 will be conducted in patients with metastatic castration-resistant PC (mCRPC) that expresses PSMA and has progressed despite prior treatment with a novel androgen axis drug (NAAD).

Conditions

Metastatic Prostate Cancer

Keywords

prostate cancer; 177Lu-DOTA-TLX591; progression free survival; overall survival; safety; gallium-68 labeled PSMA-11 (68Ga-PSMA-11) PET/CT Scan; novel androgen axis drug

Outcome Measures

Primary Outcomes (1)

• Comparison of radiographic progression-free survival (rPFS)

  Radiographic progression-free survival (rPFS) defined as the time from randomization to disease progression confirmed by central independent radiology review according to RECIST 1.1 (for soft tissue disease) and/or PCWG3 criteria (for bone disease), or death (whichever occurs first).

  Day 1 to 5 years after two administrations of 177Lu-DOTA-rosopatamab

Secondary Outcomes (24)

• Overall survival

  Day 1 to 5 years after two administrations of 177Lu-DOTA-rosopatamab

• Tumour objective response rate (ORR)

  Day 1 to 5 years after two administrations of 177Lu-DOTA-rosopatamab

• Time to a first Symptomatic Skeletal Event (SSE)

  Day 1 to 5 years after two administrations of 177Lu-DOTA-rosopatamab

• Progression-free survival

  Day 1 to 5 years after two administrations of 177Lu-DOTA-rosopatamab

• Number of participants with treatment-related adverse events as assessed by CTCAE v5.0

  Day 1 to 5 years after two administrations of 177Lu-DOTA-rosopatamab

Study Arms (3)

Group A

EXPERIMENTAL

Two single intravenous (IV) injections of 76 mCi each (equivalent to a 45 mCi/m2 dose in a standard 1.7m2 individual) of 177Lu-DOTA- rosopatamab, given 14 days apart, plus best Standard of Care

Other: 177Lu-DOTA-rosopatamb

Group B

ACTIVE COMPARATOR

Participants will receive the Standard of Care

Drug: Standard of Care

Biodistribution and Dosimetry Sub-Study

EXPERIMENTAL

Two single intravenous (IV) injections of 76 mCi each (equivalent to a 45 mCi/m2 dose in a standard 1.7m2 individual) of 177Lu-DOTA- rosopatamab, given 14 days apart, plus best Standard of Care

Other: 177Lu-DOTA-rosopatamb

Interventions

177Lu-DOTA-rosopatamb OTHER

Two single intravenous (IV) injections of 76 mCi each (equivalent to a 45 mCi/m2 dose in a standard 1.7m2 individual) of 177Lu-DOTA- rosopatamab, given 14 days apart, plus best SoC

Also known as: 177Lu-TLX591

Biodistribution and Dosimetry Sub-Study; Group A

Standard of Care DRUG

enzalutamide or abiraterone \[+ prednisone/prednisolone)\] or docetaxel

Group B

Eligibility Criteria

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

You may qualify if:

• Be a male, at least 18 years old, with metastatic adenocarcinoma of the prostate defined by histological / pathological confirmation of PC.
• Be of ECOG Performance Status 0, 1, or 2 and have an estimated life expectancy of ≥6 months.
• Have metastatic disease (≥1 metastatic lesions present on baseline CT, MRI, or bone scan imaging).
• Have castration-resistant PC (defined as disease progressing despite castration by orchiectomy or ongoing use of luteinizing hormone-releasing hormone \[LHRH\]) and must have a castrate level of serum/plasma testosterone (\<50 ng/dL or \<1.7 nmol/L).
• In the mCRPC setting, must have received a minimum of 12 weeks of prior therapy with a NAAD, either enzalutamide or abiraterone plus prednisone.
• Should have received one line of prior taxane therapy or have refused or be ineligible for taxanes
• Have a disease that is progressing at study entry, despite a castrate testosterone level (\<50 ng/dL or \<1.7 nmol/L), by the demonstration of at least one of the following:
• Rising PSA values done in sequence at least 1 week apart and with a minimal starting value of 2.0 ng/mL.
• Progressive disease or new lesion(s) in the viscera or lymph nodes as per RECIST1.1 or in bone as per Prostate Cancer Working Group 3 \[PCWG3; Scher et al., 2016\]). Any ambiguous results are to be confirmed by other imaging modality (e.g., CT or MRI scan).
• Have disease that is PSMA positive, as demonstrated by a 68Ga-PSMA11 PET/CT scan and confirmed as eligible by the Sponsor's central reader (patient must have at least one site of metastatic disease with SUVmax ≥1.5 times the SUV of normal liver). If the disease meets the criteria for PSMA positivity, but there is one or more soft tissue lesion of ≥ 2 cm that is not PSMA positive, then the patient is to be excluded on the grounds that there is substantial disease which might not respond to the therapy.
• Must have recovered to ≤ Grade 2 from all clinically significant toxicities related to prior therapies (i.e., surgery, local radiotherapy, NAAD, chemotherapy, etc.).
• Can be receiving a bisphosphonate or denosumab regimen provided that the patient has been receiving and tolerating this treatment for ≥30 days prior to randomization.
• Have adequate organ function at Screening:
• a. Bone marrow: i. Platelets ≥150×109/L. ii. Absolute neutrophil count \>1.5×109/L. iii. Hemoglobin ≥10g/dL (no red blood cell transfusion in the previous 4 weeks).
• b. Liver function: i. Total bilirubin \< 1.5×the upper limit of normal (ULN). For patients with known Gilbert's Syndrome \<3×ULN is permitted. ii. Alanine aminotransferase (ALT) or aspartate aminotransferase (AST) \<3×ULN OR \<5×ULN for patients with liver metastases. c. Renal function: i. Serum/plasma creatinine \<1.5×ULN or creatinine clearance ≥50 mL/min determined using the Cockcroft \& Gault formula.

You may not qualify if:

• Are unable to understand or are unwilling to sign a written informed consent document or to follow investigational procedures in the opinion of the Investigator.
• Have PC associated with pathological findings consistent with small cell or any histology other than adenocarcinoma of the prostate. If there are minor elements of neuroendocrine histology, this is acceptable.
• Uncontrolled pain.
• Diagnosed with other malignancies that are expected to alter life expectancy or may interfere with disease assessment. However, patients with a prior history of malignancy that has been adequately treated and who have been disease-free for more than 3 years are eligible, as are patients with adequately treated non-melanoma skin cancer, and superficial bladder cancer.
• Are at increased risk of hemorrhage or bleeding, or with a recent history of a thrombolytic event (e.g., deep vein thrombosis \[DVT\]/ pulmonary embolism \[PE\]) and have been administered long-term anti-coagulant or anti-platelet agents.
• Have received prior treatment with monoclonal antibody (mAb) J591 or HuJ591 or any other PSMA targeted therapy.
• Have known allergies, hypersensitivity, or intolerance to the investigational drug or its excipients.
• Have received prior systemic anti-cancer therapy (e.g., chemotherapy, immunotherapy, or biological therapy) and/or radiation therapy within 4 weeks of randomization OR if any significant AEs have not resolved to National Cancer Institute (NCI) AE Criteria ≤2; OR are receiving other concurrent cytotoxic chemotherapy, immunotherapy, radioligand therapy, or investigational therapy.
• Have received prior treatment with radioisotopes, including but not limited to: 89Strontium, 153Samarium, 186Rhenium, 188Rhenium, 223Radium, or hemi-body irradiation within 6 months prior to randomization.
• Have received other investigational therapy within 4 weeks of randomization.
• Have known brain metastases or hepatic metastases.
• Have a history of seizure and/or stroke within past 6 months.
• Have clinical or radiologic findings indicative of impending cord compression or experience symptomatic cord compression.
• Have a serious active or sub-clinical infection or angina pectoris (New York Heart Association \[NYHA\] Class III or IV), significantly prolonged QT interval or other serious illness(es) involving the cardiac, respiratory, central nervous system, renal, hepatic or hematological organ systems, which might impair the ability to complete this study or could interfere with determination of causality of any adverse effects experienced in this study, or which require treatment that could interact with study treatment, particularly with enzalutamide.
• Have received treatment with any PARP inhibitors (i.e., Olaparib) or with any platinum based anti-neoplastic drugs.

Sponsors & Collaborators

• Telix Pharmaceuticals (Innovations) Pty Ltd: lead

Study Sites (6)

Westmead Hospital

Westmead, New South Wales, 2145, Australia

Location

Princess Alexandra Hospital

Woolloongabba, Queensland, 4102, Australia

Location

Monash Health

Clayton, Victoria, 3168, Australia

Location

Austin Health

Melbourne, Victoria, 3083, Australia

Location

'GenesisCare Murdoch'

Murdoch, Western Australia, 6150, Australia

Location

Auckland City Hospital

Auckland, 1023, New Zealand

Location

MeSH Terms

Conditions

Prostatic Neoplasms

Interventions

Standard of Care

Condition Hierarchy (Ancestors)

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

Intervention Hierarchy (Ancestors)

Quality Indicators, Health Care; Quality of Health Care; Health Services Administration; Health Care Quality, Access, and Evaluation

Study Design

• Study Type: interventional
• Phase: phase 3
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Model Details: Approximately 387 eligible patients will be randomized to one of two groups in a 2:1 ratio to receive one of the following treatments: * Group A: Two single intravenous (IV) injections of 76 mCi each (equivalent to a 45 mCi/m2 dose in a standard 1.7m2 individual) of 177Lu-DOTA- rosopatamab, given 14 days apart, plus best SoC * Group B: Best SoC. Additionally, up to 10 patients, in New Zealand only, will be recruited for evaluation of biodistribution and dosimetry of 177Lu- DOTA-TLX591(m17 allotype) in combination with the SoC. These patients will receive two single intravenous (IV) injections of 76 mCi (±10%) each (equivalent to a 45 mCi/m2 dose in a standard 1.7m2 individual) of 177Lu-DOTA-TLX591 (m17), given 14 days apart, plus best SoC (abiraterone/prednisolone or enzalutamide or docetaxel). After the first dose, the patients will undergo single-photon emission computerized tomography/computerized tomography (SPECT/CT).

Study Record Dates

• First Submitted: May 3, 2021
• First Posted: May 6, 2021
• Study Start: August 29, 2023
• Primary Completion: July 1, 2025
• Study Completion: July 1, 2025
• Last Updated: February 20, 2026

Record last verified: 2026-02

Data Sharing

• IPD Sharing: Will not share

Locations

AU (5); NZ (1)