GB-4362 combined with enfortumab vedotin and pembrolizumab for advanced urothelial cancer

A Phase 1, Open-Label Study to Evaluate the Safety, Pharmacokinetics, and Pharmacodynamics of GB-4362 Administered With Enfortumab Vedotin and Pembrolizumab in Participants With Advanced Urothelial Cancer

Phase 1 Interventional Generate Biomedicines · NCT07484022

This study will test adding GB-4362 to enfortumab vedotin and pembrolizumab to see if it lowers treatment-related side effects like nerve damage in adults with advanced or metastatic urothelial cancer.

Quick facts

PhasePhase 1
Study typeInterventional
Enrollment37 (estimated)
Ages18 Years and up
SexAll
SponsorGenerate Biomedicines Industry-sponsored
Drugs / interventionsenfortumab, pembrolizumab, chemotherapy, prednisone
Locations2 sites (Orlando, Florida and 1 other locations)
Trial IDNCT07484022 on ClinicalTrials.gov

What this trial studies

This is a Phase 1, open-label, multicenter dose-finding trial that gives GB-4362 together with standard-dose enfortumab vedotin and pembrolizumab to adults with locally advanced or metastatic urothelial cancer. GB-4362 is a monoclonal antibody designed to bind and neutralize free MMAE, the cytotoxic payload released from enfortumab vedotin that is linked to toxicities such as peripheral neuropathy. The study uses a cohort-based dose escalation to identify safety, dose-limiting toxicities, and PK/PD effects, followed by a dose expansion at the selected dose. Exploratory endpoints include measurement of free MMAE reduction, peripheral neuropathy outcomes, dose modifications of enfortumab vedotin, and descriptive anti-tumor activity.

Who should consider this trial

Good fit: Adults (≥18) with locally advanced or metastatic urothelial cancer who are planned to start enfortumab vedotin plus pembrolizumab, have ECOG 0–1 (ECOG 2 allowed in expansion), weigh ≥50 kg, and can consent and comply with study visits are eligible.

Not a fit: Patients who previously received enfortumab vedotin or other MMAE-containing antibody–drug conjugates, or who cannot safely receive enfortumab vedotin or pembrolizumab, are unlikely to benefit from this study.

Why it matters

Potential benefit: If successful, adding GB-4362 could reduce peripheral neuropathy and other off-target toxicities, allowing safer delivery of enfortumab vedotin.

How similar studies have performed: Enfortumab vedotin combined with pembrolizumab has demonstrated anti-tumor activity in urothelial cancer, but using an antibody like GB-4362 to neutralize free MMAE is a novel approach with limited prior clinical data.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria

* Planned to receive standard-of-care treatment with enfortumab vedotin (EV) (starting dose 1.25 mg/kg) in combination with pembrolizumab for locally advanced or metastatic urothelial cancer.
* Age ≥18 years.
* ECOG Performance Status score of 0 or 1 (ECOG 2 excluded in Dose Escalation but allowed in Dose Expansion).
* Weight ≥50 kg at screening.
* Life expectancy ≥3 months, as determined by the investigator.
* Participants must provide written informed consent before any study-related activities are carried out and must be able to understand the nature and purpose of the study, including potential risks and adverse effects.
* Willing and able to comply with all study assessments and adhere to the protocol schedule and restrictions.

Exclusion Criteria

* Previously received enfortumab vedotin (EV) or other MMAE-based antibody-drug conjugates (ADCs).
* Received anti-cancer treatment with chemotherapy, biologics, or investigational agents within 4 weeks before the first dose of EV/pembrolizumab.
* Uncontrolled diabetes.
* Active CNS metastases. Participants with treated CNS metastases are permitted if all of the following criteria are met:
* CNS metastases have been clinically stable for at least 4 weeks prior to screening and baseline scans show no evidence of new or enlarged metastasis.
* The participant is on a stable dose of ≤10 mg/day of prednisone or equivalent for at least 2 weeks (if requiring steroid treatment).
* The participant does not have leptomeningeal disease.
* Ongoing clinically significant toxicity associated with prior treatment (including radiotherapy or surgery) that has not resolved to Grade ≤1 or returned to baseline.
* History of a severe (Grade ≥3) allergic or infusion-related reaction to any monoclonal antibody.
* Another underlying medical condition that, in the opinion of the investigator, would impair the ability of the participant to receive or tolerate the planned treatment and follow-up.
* Known psychiatric or substance abuse disorders that would interfere with cooperating with study requirements

Where this trial is running

Orlando, Florida and 1 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 Urothelial CancerMetastatic Urothelial CarcinomaGB-4362Enfortumab VedotinPembrolizumabPeripheral NeuropathyAntibody-Drug ConjugateMMAE
Last reviewed 2026-06-10 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.