Castration-Resistant Prostatic CancerPhase 2TamarackNCT05551117
A Study of Vobramitamab Duocarmazine in Participants With Metastatic Castration Resistant Prostate Cancer and Other Solid Tumors
A Phase 2 study testing vobramitamab duocarmazine 2.0 mg (Arm A), vobramitamab duocarmazine 2.7 mg (Arm B) and vobramitamab duocarmazine in people with Castration-Resistant Prostatic Cancer and Androgen-Independent Prostatic Cancer, run by MacroGenics at 63 sites in 9 countries.
Trial 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. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Castration-Resistant Prostatic Cancer, Androgen-Independent Prostatic Cancer, Androgen-Insensitive Prostatic Cancer
- What is being tested?
- vobramitamab duocarmazine 2.0 mg (Arm A), vobramitamab duocarmazine 2.7 mg (Arm B) and vobramitamab duocarmazine
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 192 participants
- Where
- 63 sitesin 9 countries
- Study dates
- 13 Jun 2023to 23 Jan 2025
- Phase
- Phase 2
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- 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.
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- 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.
Who cannot join
- 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.
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- 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.
Trial locations and contacts
63 sites in 9 countries.
63 sites in 9 countries
United States14 sites
The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins
Baltimore, Maryland, 21231
Gabrail Cancer Center
Canton, Ohio, 44718
University of Virginia Comprehensive Cancer Center
Charlottesville, Virginia, 22908
Pontchartrain Cancer Center
Covington, Louisiana, 70433
Barbara Ann Karmanos Cancer Institute - Hudson-Webber Cancer Research Center
Detroit, Michigan, 48201
Virginia Cancer Specalists
Fairfax, Virginia, 22031
Compassionate Cancer Care Medical Group
Fountain Valley, California, 92708
The University of Florida Health System - UF Health Urology - Jacksonville
Jacksonville, Florida, 32209
University of California Los Angeles (UCLA) Community Cancer Care
Los Angeles, California, 90095
Masonic Cancer Center, University of Minnesota
Minneapolis, Minnesota, 55455
Carolina Urologic Research Center
Myrtle Beach, South Carolina, 29572
Mid Florida Hematology and Oncology Center
Orange City, Florida, 32763
VA Portland Health Care Services
Portland, Oregon, 97239
Fred Hutchinson Cancer Center
Seattle, Washington, 98109
France11 sites
Institut Bergonié
Bordeaux, Gironde, 33076
CHRU Brest
Brest, 29200
Clinique Victor Hugo
Le Mans, Sarthe, 72000
Institut régional du Cancer de Montpellier - ICM Val d'Aurelle
Montpellier, Herault, 34298
Centre Antoine-Lacassagne
Nice, AM, 06189
Institut Mutualiste Montsouris
Paris, 75014
Centre Hospitalier Privé Saint-Grégoire
Saint-Grégoire, Ille Et Vilaine, 35760
Hôpital d'Instruction des Armées Bégin
Saint-Mandé, Île-de-France Region, 94160
Institut de Cancerologie Strasbourg Europe (ICANS)
Strasbourg, Bas Rhin, 67200
Hopital Foch
Suresnes, Île-de-France Region, 92150
Gustave Roussy
Villejuif, Val De Marne, 94800
South Korea8 sites
Kyungpook National University Chilgok Hospital
Bugok, Daegu, 41404
National Cancer Center
Goyang-si, Gyeonggi-do, 10408
Chonnam National University Hospital
Gwangju, 61469
Seoul National University Hopital
Seoul, 03080
Yonsei University Health System, Severance Hospital
Seoul, 03722
Samsung Meical Cemter
Seoul, 06351
Ewha Womans University Mokdong Hospital
Seoul, 07985
Asan Medical Center
Seoul, 5505
Spain8 sites
Hospital Del Mar
Barcelona, 08003
Hospital Clinic de Barcelona
Barcelona, 08036
Hospital de la Santa Creu I Sant Pau
Barcelona, 08036
Institut Catala d'Oncologia Hospitalet
Barcelona, 08036
Hospital Universitario Lucus Augusti
Lugo, 27002
Hospital Universitario 12 de Octubre
Madrid, 28041
Hospital Universitari Parc Taulí
Sabadell, Barcelona, 08208
Hospital Universitario Virgen del Rocio
Seville, Seville, 41013
Poland6 sites
Przychodnia Lekarska "KOMED"
Konin, WLKP, 62-500
Szpital Wojewodzki im. Mikolaja Kopernika
Koszalin, West Pomeranian Voivodeship, 75-581
Szpital im. Fryderyka Chopina
Otwock, Masovian Voivodeship, 05-400
Magodent Szpital Elblaska
Warsaw, Masovian Voivodeship, 01-748
Medical Concierge Centrum Medyczne
Warsaw, Masovian Voivodeship, 02-798
Grochowski Hospital
Warsaw, Masovian Voivodeship, 04-073
Belgium5 sites
(Grand Hopital de Charleroi) GHDC
Charleroi, Hainaut, 6000
Algemeen Ziekenhuis Maria Middelares
Ghent, 9000
Centre Hospitalier Universitaire (CHU) - Universite Catholique de Louvain (UCL) - Namur - Site Godinne (Cliniques Universitaires UCL de Mont-Godinne)
Godinne, Namur, 5300
Centre Hospitalier de Ardenne - Libramont - Clinique du Sein
Libramont, Luxembourg, 6800
Cliniques Universitaires Saint-Luc
Woluwe-Saint-Lambert, Brussles, 1200
Italy5 sites
Radiation Oncology Unit, Azienda Ospedaliera Universitaria Careggi, University of Florence
Florence, 50134
Ospedale dell'Angelo
Mestre, Venice, 30174
AOU San Luigi Gonzaga Oncology Department
Orbassano, TO, 10049
Istituto Oncologico Veneto
Padova, 35128
Azienda Provinciale per i Servizi Sanitari - Presidio Ospedaliero S. Chiara
Trento, 38122
Australia4 sites
Cabrini Health- Malvern
Malvern, Victoria, 3144
Peter MacCallum Cancer Centre
Melbourne, Victoria, 3000
Ramsay Health Care - Westmead Private Hospital
Westmead, New South Wales, 2145
The University of Queensland (UQ) - Princess Alexandra Hospital (PAH)
Woolloongabba, Queensland, 4102
United Kingdom2 sites
Oxford University Hospitals NHS- Churchill Hospital
Oxford, OX3 7LE
The Royal Marsden NHS Trust
Sutton, Surrey, SM2 5PT
About this study
Official title: A Phase 2, Open-label, Study of Vobramitamab Duocarmazine in Participants With Metastatic Castration-resistant Prostate Cancer and Other Solid Tumors
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.
Read more
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.
- Conditions
- Castration-Resistant Prostatic Cancer, Androgen-Independent Prostatic Cancer, Androgen-Insensitive Prostatic Cancer, Androgen-Resistant Prostatic Cancer, Hormone Refractory Prostatic Cancer, Anal Cancer
- Being tested
- vobramitamab duocarmazine 2.0 mg (Arm A), vobramitamab duocarmazine 2.7 mg (Arm B), vobramitamab duocarmazine, Abiraterone, Enzalutamide
- Medical subject headings
- Prostatic Neoplasms, Castration-Resistant, Anus Neoplasms, Squamous Cell Carcinoma of Head and Neck, Melanoma, Carcinoma, Non-Small-Cell Lung, Small Cell Lung Carcinoma, Carcinoma, Small Cell
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
vobramitamab duocarmazine 2.0 mg (Arm A)Biological
Also called MGC018
2.0 mg/kg intravenous (IV) every 4 weeks
vobramitamab duocarmazine 2.7 mg (Arm B)Biological
Also called MGC018
2.7 mg.kg IV every 4 weeks
vobramitamab duocarmazineBiological
Also called MGC018
2.7 mg.kg IV every 4 weeks
AbirateroneDrug
1000 mg once daily
EnzalutamideDrug
160 mg daily
| Study group | Role | What they receive |
|---|---|---|
| Part 1: MGC018 2.0 mg (Arm A) | Experimental | MGC018 2.0 mg/kg every 4 weeks Receives: Biological: vobramitamab duocarmazine 2.0 mg (Arm A) |
| Part 1: MGC018 2.7 mg (Arm B) | Experimental | MGC018 2.7 mg/kg every 4 weeks Receives: Biological: vobramitamab duocarmazine 2.7 mg (Arm B) |
| Part 2 | Experimental | MGC018 2.7 mg/kg every 4 weeks Receives: Biological: vobramitamab duocarmazine |
| Part 1: Control Arm | Active comparator | Patients are administered abiraterone or enzalutamide Receives: Drug: Abiraterone; Drug: Enzalutamide |
What is being measured
The primary outcome is the main question the study is designed to answer.
Part 1: Six-month Radiographic Progression Free Survival (rPFS) as Determined by the Investigator
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.
Measured: Assessed every 8 weeks for six months. Six month data reported.
Part 2: Objective Response Rate (ORR) Per Investigator Assessment of Response Evaluation Criteria in Solid Tumours (RECIST) 1.1 Criteria
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.
Measured: Every 8 weeks for the first 24 weeks, then every 12 weeks. Average duration of participation, 10 months.
Secondary outcomes (12)
Part 1: ORR Per PCWG3 Criteria as Determined by the Investigator
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
Measured: Every 8 weeks for the first 24 weeks, then every 12 weeks. Average duration of participation, 10 months,
Part 1: Median Duration of Response (DoR) Per PCWG3 Criteria as Determined by the Investigator
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.
Measured: Every 8 weeks for the first 24 weeks, then every 12 weeks. Average duration of participation, 10 months.
Part 1: Mean Best Tumor Size Change Over Time
Measured: Every 8 weeks for the first 24 weeks, then every 12 weeks. Average duration of participation, 10 months.
Part 1: Prostate-specific Cancer Antigen (PSA) Response Rate Per PCWG3 Criteria
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%.
Measured: Every 4 weeks throughout study participation. Average duration 10 months.
Part 1: Time to PSA Progression Per PCWG3 Criteria
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.
Measured: Every 4 weeks throughout study participation. Average duration of participation, 10 months.
Part 1: Duration of PSA Response Per PCWG3 Criteria
Duration of PSA response is defined as the time from the date of first documented PSA response to the earliest date of PSA progression.
Measured: Every 4 weeks throughout study participation. Average duration of participation, 10 months.
Part 1: Best PSA Percent Change
Measured: Every 4 weeks throughout study participation. Average duration of participation, 10 months.
Part 1: Time to First Symptomatic Skeletal Event (SSE)
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.
Measured: Every 4 weeks throughout the study. Average duration of participation, 10 months.
Number of Participants With Adverse Event (AEs), Serious AEs (SAEs), and AEs Leading to Study Treatment Discontinuation.
Measured: Throughout the study, average duration of participation, 10 months.
Number of Participants Who Develop Anti-drug Antibodies (ADA)
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.
Measured: Every 4 weeks throughout the study, average duration of participation was 10 months.
Part 2: Median DoR Per Investigator Assessment of RECIST 1.1 Criteria
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.
Measured: Every 8 weeks for the first 24 weeks, then every 12 weeks. Average duration of participation, 10 months.
Part 2: Median Progression Free Survival (PFS) Per Investigator Assessment of RECIST 1.1 Criteria
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.
Measured: Every 8 weeks for the first 24 weeks, then every 12 weeks. Average duration of participation, 10 months.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted22 Sep 2022
- Study start13 Jun 2023
- Primary completion4 Jul 2024
- Study completion23 Jan 2025
Why it stopped: Business reasons
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Other trials for Castration-Resistant Prostatic CancerStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 2
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 192 participants (actual)
Sponsor and investigators
- Lead sponsor
- MacroGenics
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Liudmila Schafer, M.D., Study director, MacroGenics
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05551117
- Sponsor's protocol ID
- CP-MGC018-03
- Acronym
- Tamarack
- Status last verified
- Jan 2026
- First submitted
- 19 Sep 2022
- Last updated
- 9 Feb 2026
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 9 Feb 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Phase 2, Open-label, Study of Vobramitamab Duocarmazine in Participants With Metastatic Castration-resistant Prostate Cancer and Other Solid Tumors
- ClinicalTrials.gov ID
- NCT05551117
- Acronym / sponsor ID
- Tamarack / CP-MGC018-03
- Conditions
- Castration-Resistant Prostatic Cancer, Androgen-Independent Prostatic Cancer, Androgen-Insensitive Prostatic Cancer, Androgen-Resistant Prostatic Cancer, Hormone Refractory Prostatic Cancer, Anal Cancer
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- TerminatedReason stopped: Business reasons
- Enrolment
- 192 participants (actual)
- Lead sponsor
- MacroGenicsIndustry (pharma, biotech, devices)
- Study start
- 13 Jun 2023 (actual)
- Primary completion
- 4 Jul 2024 (actual)
- Study completion
- 23 Jan 2025 (actual)
- First posted
- 22 Sep 2022 (actual)
- Results
- Posted 9 Feb 2026
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
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.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 4
| Arm | Type | Receives |
|---|---|---|
| Part 1: MGC018 2.0 mg (Arm A) | Experimental | Biological: vobramitamab duocarmazine 2.0 mg (Arm A)MGC018 2.0 mg/kg every 4 weeks |
| Part 1: MGC018 2.7 mg (Arm B) | Experimental | Biological: vobramitamab duocarmazine 2.7 mg (Arm B)MGC018 2.7 mg/kg every 4 weeks |
| Part 2 | Experimental | Biological: vobramitamab duocarmazineMGC018 2.7 mg/kg every 4 weeks |
| Part 1: Control Arm | Active comparator | Drug: Abiraterone, Drug: EnzalutamidePatients are administered abiraterone or enzalutamide |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (10 listed)
- 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.
Key exclusion criteria (10 listed)
- 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.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| vobramitamab duocarmazine 2.0 mg (Arm A)Also: MGC0182.0 mg/kg intravenous (IV) every 4 weeks | Biological | Part 1: MGC018 2.0 mg (Arm A) |
| vobramitamab duocarmazine 2.7 mg (Arm B)Also: MGC0182.7 mg.kg IV every 4 weeks | Biological | Part 1: MGC018 2.7 mg (Arm B) |
| vobramitamab duocarmazineAlso: MGC0182.7 mg.kg IV every 4 weeks | Biological | Part 2 |
| Abiraterone1000 mg once daily | Drug | Part 1: Control Arm |
| Enzalutamide160 mg daily | Drug | Part 1: Control Arm |
Primary outcome
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.
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.
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.
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.
12 secondary outcomes
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,
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.
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.
Part 1: Prostate-specific Cancer Antigen (PSA) Response Rate Per PCWG3 Criteria
Time frame: Every 4 weeks throughout study participation. Average duration 10 months.
Part 1: Time to PSA Progression Per PCWG3 Criteria
Time frame: Every 4 weeks throughout study participation. Average duration of participation, 10 months.
Part 1: Duration of PSA Response Per PCWG3 Criteria
Time frame: Every 4 weeks throughout study participation. Average duration of participation, 10 months.
Part 1: Best PSA Percent Change
Time frame: Every 4 weeks throughout study participation. Average duration of participation, 10 months.
Part 1: Time to First Symptomatic Skeletal Event (SSE)
Time frame: Every 4 weeks throughout the study. Average duration of participation, 10 months.
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.
Number of Participants Who Develop Anti-drug Antibodies (ADA)
Time frame: Every 4 weeks throughout the study, average duration of participation was 10 months.
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.
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.
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 9 Feb 2026.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- Individual participant dataSharing planned: No
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Metastatic Castration-resistant Prostate Cancer
Active, not recruitingPhase 2
Study of TGF-β Receptor Inhibitor Galunisertib (LY2157299) and Enzalutamide in Metastatic Castration-resistant Prostate Cancer
Prostate Cancer
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Liudmila Schafer, M.D. study director
MacroGenics
63 sites in 9 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing vobramitamab duocarmazine 2.0 mg (Arm A), vobramitamab duocarmazine 2.7 mg (Arm B) and vobramitamab duocarmazine in people with Castration-Resistant Prostatic Cancer and Androgen-Independent Prostatic Cancer, run by MacroGenics at 63 sites in 9 countries.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 10 inclusion and 10 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: stopped early, as of the sponsor's last update on 9 Feb 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 63 sites in United States, France, South Korea, Spain, Poland and 4 more countries. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
Yes. Results are posted in the registry (first posted 9 Feb 2026). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome 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.). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 9 Feb 2026.