Study of JANX007 in Subjects With Metastatic Castration-Resistant Prostate Cancer (ENGAGER-PSMA-01)

About This Trial

This study is testing an experimental medicine called JANX007 to find safe doses, monitor side effects, and see if it can help fight advanced prostate cancer.
It is designed for men whose cancer has spread to other parts of the body and has continued to grow despite receiving standard hormone treatments or chemotherapy.
Because this is an early-stage study testing the drug in people for the first time, the main goal is to see how the human body handles the medicine rather than guaranteeing a cure.
Before considering this trial, patients should know that those with serious heart problems or who have already received certain advanced targeted treatments will not be eligible to participate.

This study is a first-in-human, Phase 1, open-label, multicenter study to assess the safety, tolerability, pharmacokinetic (PK), pharmacodynamic (PD), and the preliminary efficacy of JANX007 in adults with metastatic castration-resistant prostate cancer (mCRPC).

Age Range: 18 - 100 years
Gender: Male
Who This Trial is For: This study is testing an experimental medicine called JANX007 to find safe doses, monitor side effects, and see if it can help fight advanced prostate cancer.

Full Eligibility Criteria

Inclusion Criteria

Male ≥18 years of age at the time of signing informed consent
Histologically or cytologically confirmed adenocarcinoma of the prostate
For Dose Escalation and Backfill: Having mCRPC that progressed after at least one novel anti-androgen therapy and at least one taxane containing regimen. Participants who have actively refused a taxane containing regimen or are medically unsuitable to receive taxane are eligible
Adequate organ function
For Monotherapy Expansion Part a: Have received ≤ 2 anti-androgen therapies in either the HSPC or CRPC setting and no more than 1 prior taxane regimen in the HSPC or CRPC setting. Participants who have actively refused a taxane regimen or are medically unsuitable to receive taxane are eligible.
For Monotherapy Expansion Part b: Have received ≤ 2 anti-androgen therapies in either the HSPC or CRPC settings
For Monotherapy Expansion Part d: Have received ≤ 1 anti-androgen therapy and a poly(ADP-ribose) polymerase (PARP) inhibitor for mCRPC and have progressed following treatment with the PARP inhibitor
For Combination Expansion: Have received ≤ 1 anti-androgen therapy other than darolutamide in the HSPC setting and ≤ 1 taxane in the mCRPC setting. Participants who have actively refused a taxane regimen or are medically unsuitable to receive taxane are eligible.

Exclusion Criteria

Prior solid organ transplant
Prior treatment with PSMA-targeted CAR-T cell therapy or PSMA-CD3, PSMA-CD28 or other CD3 T-cell engaging bispecific antibodies or radioligand therapy
Clinically significant cardiovascular disease
For Monotherapy Expansion Part a: Prior receipt of any treatment other than an ARPI or taxane in the mCRPC setting
For Monotherapy Expansion Part b: Prior receipt of any treatment other than an anti-androgen therapy or prior receipt of a taxane containing regimen or more than 1 prior line of therapy for mCRPC
For Monotherapy Part d: More than 1 prior line of therapy for mCRPC or prior receipt of any treatment other than an anti-androgen therapy and PARP inhibitor for mCRPC or prior receipt of a taxane in the mCRPC setting
For Combination expansion: More than 1 prior line of therapy for mCRPC or prior receipt of any treatment other than a taxane for mCRPC or prior receipt of Darolutamide or prior receipt of a taxane for HSPC
Active clinically significant infection (bacterial, viral, fungal, mycobacteria or other)
Any medical condition or clinical laboratory abnormality likely to interfere with assessment of safety or efficacy of study treatment