Open Actively Recruiting

A Study of Two Dose Levels of Vobramitamab Duocarmazine in Participants With Metastatic Castration Resistant Prostate Cancer


Brief Summary

Study CP-MGC018-03 is a randomized, open-label, Phase 2 study. 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 taxane-containing regimen, but no other chemotherapy agents.

The study will assess efficacy and tolerability of two vobramitamab duocarmazine (MGC018) experimental arms (2.0 mg/kg every 4 weeks [Q4W] and 2.7 mg/kg Q4W) . Approximately 100 participants will be randomized 1:1. Vobramitamab duocarmazine will be administered intravenously (IV) in clinic on Day 1 of each 4-week cycle. Vobramitamab duocarmazine will be administered for up to 26 cycles, approximately 2 years, 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. An analysis of radiographic progression-free survival (rPFS) will occur after 100 participants have been on-study for at least 6 months.
Primary Purpose
Study Type
Phase II/III


Healthy Volunteers
Minimum Age
18 Years
Maximum Age

Inclusion Criteria:

  • Histologically confirmed adenocarcinoma of the prostate without evidence of neuroendocrine differentiation, signet cell, or small cell features.
  • Participants must have ≥ 1 metastatic lesion that is present on magnetic resonance imaging (MRI), computed tomography (CT), or bone scan obtained ≤ 28 days prior to initiation of study treatment.
  • Tumor progression at study entry documented by PSA or imaging per PCWG3 criteria
  • 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.
  • Availability of archival or formalin-fixed paraffin-embedded (FFPE) tumor tissue sample for participants with metastasis to internal organs
  • Acceptable physical condition and laboratory values.

Exclusion Criteria:

  • Any underlying medical or psychiatric condition impairing participant's ability to receive, tolerate, or comply with the planned treatment or study procedures.
  • Received >1 prior taxane-containing regimen for prostate cancer. A second taxane regimen of <60 days used as bridging for lutetium-177 is permitted.
  • Received >3 total prior therapies for mCRPC
  • 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.
  • Use of products that have published anti-prostate cancer activity or are known to decrease PSA.

Join this Trial

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Study Stats
Protocol No.
Prostate Cancer
Principal Investigator
Sandy Hernandez Centeno
  • UCLA Santa Monica
For Providers
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