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NCT05551117 · REGISTRY CONDITION SEARCH

A Study of Vobramitamab Duocarmazine in Participants With Metastatic Castration Resistant Prostate Cancer and Other Solid Tumors

Found through the registry condition index, not selected as a treatment recommendation. This discovery collection was restricted to studies with posted results.

Phase
PHASE2
Status at capture
TERMINATED
Registry last update
2026-02-09

Study CP-MGC018-03 is an open-label, two-part, Phase 2 study. Part 1 of the study will enroll participants with metastatic castration-resistant prostate cancer (mCRPC) previously treated with one prior androgen receptor axis-targeted therapy (ARAT). ARAT includes abiraterone, enzalutamide, or apalutamide. Participants may have received up to 1 prior docetaxel-containing regimen, but no other chemotherapy agents. This part of the study will assess the efficacy and tolerability of vobramitamab duocarmazine (MGC018) in two experimental arms (2.0 mg/kg every 4 weeks \[Q4W\] and 2.7 mg/kg Q4W) . Approximately 100 participants will be randomized 1:1. Part 2 of the study will enroll participants with locally advanced or metastatic solid tumors. Participants must have progressive following at least 1 prior line of standard chemotherapy for advanced or metastatic disease. Participants will receive vobramitamab duocarmazine at a dose of 2.7 mg/kg every 4 weeks. Up to 200 participants may be enrolled in Part 2. In both parts, vobramitamab duocarmazine will be administered intravenously (IV) in clinic on Day 1 of each 4-week cycle. Vobramitamab duocarmazine will be administered until criteria for treatment discontinuation are met. Participants will undergo regular testing for signs of disease progression using computed tomography (CT) scans, magnetic resonance imaging (MRI), bone scans, and prostate-specific antigen (PSA) blood tests. Routine examinations and blood tests will be performed and evaluated by the study doctor.

Open the original ClinicalTrials.gov record → · Download preserved record

What did the study report?

Outcomes, safety and baseline populations are separate source sections. Quality-of-life measures appear under their original outcome titles.

flow

Participant flow

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baseline

Baseline characteristics

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outcome · POSTED

Part 1: Six-month Radiographic Progression Free Survival (rPFS) as Determined by the Investigator

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outcome · POSTED

Part 2: Objective Response Rate (ORR) Per Investigator Assessment of Response Evaluation Criteria in Solid Tumours (RECIST) 1.1 Criteria

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outcome · POSTED

Part 1: ORR Per PCWG3 Criteria as Determined by the Investigator

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outcome · POSTED

Part 1: Median Duration of Response (DoR) Per PCWG3 Criteria as Determined by the Investigator

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outcome · POSTED

Part 1: Mean Best Tumor Size Change Over Time

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outcome · POSTED

Part 1: Prostate-specific Cancer Antigen (PSA) Response Rate Per PCWG3 Criteria

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outcome · POSTED

Part 1: Time to PSA Progression Per PCWG3 Criteria

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outcome · POSTED

Part 1: Duration of PSA Response Per PCWG3 Criteria

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outcome · POSTED

Part 1: Best PSA Percent Change

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outcome · POSTED

Part 1: Time to First Symptomatic Skeletal Event (SSE)

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outcome · POSTED

Number of Participants With Adverse Event (AEs), Serious AEs (SAEs), and AEs Leading to Study Treatment Discontinuation.

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outcome · POSTED

Number of Participants Who Develop Anti-drug Antibodies (ADA)

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outcome · POSTED

Part 2: Median DoR Per Investigator Assessment of RECIST 1.1 Criteria

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outcome · POSTED

Part 2: Median Progression Free Survival (PFS) Per Investigator Assessment of RECIST 1.1 Criteria

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adverse events

Adverse events

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more info

Limitations, agreements, and source contact

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Who could take part
eligibility Criteria
Inclusion Criteria: * Part 1 only: Histologically confirmed adenocarcinoma of the prostate without evidence of neuroendocrine differentiation, signet cell, or small cell features. * Part 2 only: Histologically confirmed SCC or the anus, melanoma, HNSCC, squamous NSCLC, or SCLC. * Part 1 only: Received 1 prior ARAT for metastatic or non-metastatic, castration-sensitive or castration-resistant prostate cancer. A second ARAT regimen of \<60 days used as bridging to lutetium-177 is permitted. Up to 3 total prior lines of therapy for mCRPC are permitted.. * Part 2 only: At least 1 prior line of systemic therapy for unresectable or metastatic disease and no more than 2 prior lines of cytotoxic chemotherapy. Participants with HNSCC or melanoma must have received prior PD-1 or PD-L1 inhibitor for advanced or metastatic disease. * All participants must have ≥ 1 metastatic lesion, according to RECIST 1.1 or PCWG3 criteria, that is present on magnetic resonance imaging (MRI), computed tomography (CT), or bone scan obtained ≤ 28 days prior to initiation of study treatment. * All participants must have tumor progression, according to disease-specific criteria, following their most recent anti-cancer therapy. * All participants must have and available archival or formalin-fixed paraffin-embedded (FFPE) tumor tissue sample for participants with metastasis to internal organs * All participants have acceptable physical condition and laboratory values. * All participants of childbearing potential must agree to use highly effective methods of birth control. * All participants must not be pregnant, planning to be pregnant, or breastfeeding. Exclusion Criteria: * Any underlying medical or psychiatric condition impairing participant's ability to receive, tolerate, or comply with the planned treatment or study procedures. * Part 1 only: Received \>1 prior taxane-containing regimen for prostate cancer. A second taxane regimen of \<60 days used as bridging for lutetium-177 is permitted. * Part 1 only: Received \>3 total prior therapies for mCRPC * Part 1 only: Participants with known BRCA or ATM mutation (germline or somatic) are not eligible unless they received prior treatment with a PARP inhibitor where available, indicated and tolerated. * Another hematologic or solid tumor ≥ stage 1 malignancy that completed surgery, last dose of radiotherapy, or last dose of systemic anti-cancer therapy ≤ 2 years from first dose of study treatment. Participants who had curative therapy for non-melanomatous skin cancer or for localized malignancy are eligible. * Untreated, symptomatic central nervous system (CNS) metastasis. * Prior treatment with any B7-H3 targeted agent for cancer, * Contradictions to the use of corticosteroid treatment * Prior stem cell, tissue, or solid organ transplant. * Part 1 only: Use of products that have published anti-prostate cancer activity or are known to decrease PSA.
healthy Volunteers
false
minimum Age
18 Years
sex
ALL
std Ages
  1. ADULT
  2. OLDER_ADULT
Treatment arms and interventions
arm Groups
  1. description
    MGC018 2.0 mg/kg every 4 weeks
    intervention Names
    1. Biological: vobramitamab duocarmazine 2.0 mg (Arm A)
    label
    Part 1: MGC018 2.0 mg (Arm A)
    type
    EXPERIMENTAL
  2. description
    MGC018 2.7 mg/kg every 4 weeks
    intervention Names
    1. Biological: vobramitamab duocarmazine 2.7 mg (Arm B)
    label
    Part 1: MGC018 2.7 mg (Arm B)
    type
    EXPERIMENTAL
  3. description
    MGC018 2.7 mg/kg every 4 weeks
    intervention Names
    1. Biological: vobramitamab duocarmazine
    label
    Part 2
    type
    EXPERIMENTAL
  4. description
    Patients are administered abiraterone or enzalutamide
    intervention Names
    1. Drug: Abiraterone
    2. Drug: Enzalutamide
    label
    Part 1: Control Arm
    type
    ACTIVE_COMPARATOR
interventions
  1. arm Group Labels
    1. Part 1: MGC018 2.0 mg (Arm A)
    description
    2.0 mg/kg intravenous (IV) every 4 weeks
    name
    vobramitamab duocarmazine 2.0 mg (Arm A)
    other Names
    1. MGC018
    type
    BIOLOGICAL
  2. arm Group Labels
    1. Part 1: MGC018 2.7 mg (Arm B)
    description
    2.7 mg.kg IV every 4 weeks
    name
    vobramitamab duocarmazine 2.7 mg (Arm B)
    other Names
    1. MGC018
    type
    BIOLOGICAL
  3. arm Group Labels
    1. Part 2
    description
    2.7 mg.kg IV every 4 weeks
    name
    vobramitamab duocarmazine
    other Names
    1. MGC018
    type
    BIOLOGICAL
  4. arm Group Labels
    1. Part 1: Control Arm
    description
    1000 mg once daily
    name
    Abiraterone
    type
    DRUG
  5. arm Group Labels
    1. Part 1: Control Arm
    description
    160 mg daily
    name
    Enzalutamide
    type
    DRUG
Study design
allocation
RANDOMIZED
intervention Model
PARALLEL
masking Info
masking
NONE
primary Purpose
TREATMENT
Enrollment
count
192
type
ACTUAL
Registered outcome plans (not posted results)
primary Outcomes
  1. description
    The landmark analysis for 6 month rPFS rate will occur when all participants on Part 1 have been on study for at least 6 months.
    measure
    Part 1: Six-month Radiographic Progression Free Survival (rPFS) as Determined by the Investigator
    time Frame
    Assessed every 8 weeks for six months. Six month data reported.
  2. description
    The ORR is defined as the percentage of participants in the response evaluable population who achieve a best overall response of complete response (CR) or partial response (PR), per RECIST version 1.1 criterial CR is defined as disappearance of all target and non-target lesions. PR is defined as at least a 30% decrease from baseline in the sum of diameters of target lesions.
    measure
    Part 2: Objective Response Rate (ORR) Per Investigator Assessment of Response Evaluation Criteria in Solid Tumours (RECIST) 1.1 Criteria
    time Frame
    Every 8 weeks for the first 24 weeks, then every 12 weeks. Average duration of participation, 10 months.
secondary Outcomes
  1. description
    To qualify as an objective response, CR and PR require confirmation at least 4 weeks after initial observation of complete response (CR) or partial response (PR). CR + PR = ORR
    measure
    Part 1: ORR Per PCWG3 Criteria as Determined by the Investigator
    time Frame
    Every 8 weeks for the first 24 weeks, then every 12 weeks. Average duration of participation, 10 months,
  2. description
    The DoR will be calculated as the time from the date of initial tumor response (CR or PR) to the date of first documented PD or death from any cause, whichever occurs first.
    measure
    Part 1: Median Duration of Response (DoR) Per PCWG3 Criteria as Determined by the Investigator
    time Frame
    Every 8 weeks for the first 24 weeks, then every 12 weeks. Average duration of participation, 10 months.
  3. measure
    Part 1: Mean Best Tumor Size Change Over Time
    time Frame
    Every 8 weeks for the first 24 weeks, then every 12 weeks. Average duration of participation, 10 months.
  4. description
    PSA response is defined as a ≥ 50% decline in PSA from baseline with PSA confirmation ≥ 3 weeks after the first documented reduction in PSA of ≥ 50%.
    measure
    Part 1: Prostate-specific Cancer Antigen (PSA) Response Rate Per PCWG3 Criteria
    time Frame
    Every 4 weeks throughout study participation. Average duration 10 months.
  5. description
    In participants with a decrease in PSA from baseline, PSA progression is defined as a ≥ 25% increase and an absolute increase of ≥ 2 ng/mL above the nadir value, which is confirmed by a consecutive second value obtained ≥ 3 weeks later. In participants with no decrease in PSA from baseline, PSA progression is defined as a ≥ 25% increase and an absolute increase of ≥ 2 ng/mL above the baseline value after 12 weeks. Time to PSA progression is defined as the time from the date of randomization to the first PSA progression.
    measure
    Part 1: Time to PSA Progression Per PCWG3 Criteria
    time Frame
    Every 4 weeks throughout study participation. Average duration of participation, 10 months.
  6. description
    Duration of PSA response is defined as the time from the date of first documented PSA response to the earliest date of PSA progression.
    measure
    Part 1: Duration of PSA Response Per PCWG3 Criteria
    time Frame
    Every 4 weeks throughout study participation. Average duration of participation, 10 months.
  7. measure
    Part 1: Best PSA Percent Change
    time Frame
    Every 4 weeks throughout study participation. Average duration of participation, 10 months.
  8. description
    An SSE is defined as any of the following events: new symptomatic pathological fracture, requirement for radiation therapy to relieve bone pain, spinal cord compression, or tumor-related orthopedic surgical intervention. The time to first SSE is defined as the time from the date of randomization to the first occurrence of SSE.
    measure
    Part 1: Time to First Symptomatic Skeletal Event (SSE)
    time Frame
    Every 4 weeks throughout the study. Average duration of participation, 10 months.
  9. measure
    Number of Participants With Adverse Event (AEs), Serious AEs (SAEs), and AEs Leading to Study Treatment Discontinuation.
    time Frame
    Throughout the study, average duration of participation, 10 months.
  10. description
    Participant specimens were evaluated for the presence of ADA beginning a baseline and throughout the study. If at any time during the study, the results show evidence of ADA, they were counted as ADA positive. There was no time-to- event analysis nor by visit analysis of the data.
    measure
    Number of Participants Who Develop Anti-drug Antibodies (ADA)
    time Frame
    Every 4 weeks throughout the study, average duration of participation was 10 months.
  11. description
    The DoR will be calculated as the time from the date of initial tumor response (CR or PR) to the date of first documented progressive disease (PD) or death from any cause, whichever occurs first.
    measure
    Part 2: Median DoR Per Investigator Assessment of RECIST 1.1 Criteria
    time Frame
    Every 8 weeks for the first 24 weeks, then every 12 weeks. Average duration of participation, 10 months.
  12. description
    PFS is defined as the time from the date of the first dose to the date of first PD per RECIST 1.1 criteria or death from any cause, whichever occurs first.
    measure
    Part 2: Median Progression Free Survival (PFS) Per Investigator Assessment of RECIST 1.1 Criteria
    time Frame
    Every 8 weeks for the first 24 weeks, then every 12 weeks. Average duration of participation, 10 months.
Full study description
brief Summary
Study CP-MGC018-03 is an open-label, two-part, Phase 2 study. Part 1 of the study will enroll participants with metastatic castration-resistant prostate cancer (mCRPC) previously treated with one prior androgen receptor axis-targeted therapy (ARAT). ARAT includes abiraterone, enzalutamide, or apalutamide. Participants may have received up to 1 prior docetaxel-containing regimen, but no other chemotherapy agents. This part of the study will assess the efficacy and tolerability of vobramitamab duocarmazine (MGC018) in two experimental arms (2.0 mg/kg every 4 weeks \[Q4W\] and 2.7 mg/kg Q4W) . Approximately 100 participants will be randomized 1:1. Part 2 of the study will enroll participants with locally advanced or metastatic solid tumors. Participants must have progressive following at least 1 prior line of standard chemotherapy for advanced or metastatic disease. Participants will receive vobramitamab duocarmazine at a dose of 2.7 mg/kg every 4 weeks. Up to 200 participants may be enrolled in Part 2. In both parts, vobramitamab duocarmazine will be administered intravenously (IV) in clinic on Day 1 of each 4-week cycle. Vobramitamab duocarmazine will be administered until criteria for treatment discontinuation are met. Participants will undergo regular testing for signs of disease progression using computed tomography (CT) scans, magnetic resonance imaging (MRI), bone scans, and prostate-specific antigen (PSA) blood tests. Routine examinations and blood tests will be performed and evaluated by the study doctor.
Source references
Source notices and limitations
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    Preserved source evidence · Not medical advice