Treatment of advanced PSMA-positive tumors with CB307

A Phase 1 Open-Label, Dose Escalation and Expansion Trial to Investigate the Safety, Pharmacokinetics and Pharmacodynamics of CB307, a Trispecific Humabody® T-cell Enhancer, in Patients With PSMA+ Advanced and/or Metastatic Solid Tumours

Phase 1 Interventional Crescendo Biologics Ltd. · NCT04839991

This study is testing a new treatment called CB307 for people with advanced prostate cancer to see if it can help them feel better and live longer.

Quick facts

PhasePhase 1
Study typeInterventional
Enrollment70 (estimated)
Ages18 Years and up
SexAll
SponsorCrescendo Biologics Ltd. Industry-sponsored
Drugs / interventionspembrolizumab
Locations20 sites (Seattle, Washington and 19 other locations)
Trial IDNCT04839991 on ClinicalTrials.gov

What this trial studies

This is a Phase 1, open-label, multi-center study evaluating CB307, a trispecific Humabody® T-cell enhancer, in patients with advanced and/or metastatic PSMA-positive solid tumors. The study consists of a dose escalation phase to determine the maximum tolerated dose (MTD) and a cohort expansion phase assessing the safety and efficacy of CB307 alone and in combination with pembrolizumab for patients with metastatic castration-resistant prostate cancer. Approximately 70 patients will participate, receiving treatment until loss of clinical benefit or unacceptable toxicity occurs.

Who should consider this trial

Good fit: Ideal candidates are adults aged 18 and older with histologically confirmed PSMA-positive advanced or metastatic solid tumors who are not amenable to standard care.

Not a fit: Patients with autoimmune diseases, brain metastases, or those who have previously experienced intolerable toxicity from certain immunotherapies may not benefit from this study.

Why it matters

Potential benefit: If successful, this treatment could provide a new therapeutic option for patients with advanced PSMA-positive tumors who have limited standard care options.

How similar studies have performed: While this approach is novel, similar studies targeting PSMA-positive tumors have shown promise, indicating potential for success.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

1. Capable of understanding the written informed consent
2. Aged at least 18 years
3. Not amenable to standard of care
4. ECOG PS \<=2
5. Has documented histologically confirmed diagnosis of PSMA+ advanced or metastatic solid tumours
6. Has radiologically measurable disease per RECIST v1.1 or elevated serum PSA for castration resistant prostate cancer patients with only bone metastasis
7. Adequate organ function

Exclusion Criteria:

1. Subjects with autoimmune disease or regular immunosuppressants
2. Has discontinued from anti-CTLA 4, anti-PD1 or anti-PD(L)1 antibody because of intolerable toxicity
3. Has brain metastasis including leptomeningeal metastasis or primary brain tumour
4. Has current or history of CNS disease
5. Has known active infection
6. Part 2B only - has prior treatment with anti PD(L)1 or anti CTLA4

Where this trial is running

Seattle, Washington and 19 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Advanced and/or Metastatic Solid TumoursProstate Specific Membrane AntigenSolid TumoursCastration-resistant prostate cancerFirst in HumanPhase 1 StudyCD1374-1BB
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.