Sun Yat-Sen Treatment Strategy for Enhancing Response in Muscle-invasive Bladder Cancer

Summary

This is a multicenter, prospective, open-label, Phase II, four-arm parallel study evaluating the efficacy and safety of different sensitization strategies combined with disitamab vedotin and toripalimab in patients with HER2-positive muscle-invasive urothelial carcinoma of the bladder (MIBC).

Eligible patients with cT2-4aN0M0 HER2-positive urothelial carcinoma of the bladder will receive neoadjuvant disitamab vedotin plus toripalimab in combination with one of four sensitizing agents: sitagliptin, tazemetostat, tafolecimab, or ursodeoxycholic acid.

After six cycles of neoadjuvant treatment, patients will undergo comprehensive response assessment, including imaging, cystoscopy, urine cytology, and complete transurethral resection of bladder tumor (cTURBT). Patients who achieve a clinical complete response (cCR) may enter a bladder-preservation treatment pathway, including additional disitamab vedotin plus toripalimab and subsequent toripalimab maintenance therapy. Patients who do not achieve cCR will be considered for salvage radical cystectomy.

The primary objective is to evaluate the cCR rate of each treatment strategy. Secondary objectives include bladder-intact disease-free survival, overall survival, bladder preservation rate, safety, quality of life, treatment costs, and exploratory biomarker analyses.

Conditions

• Bladder Urothelial Carcinoma
• Bladder Cancer

Interventions

DRUG

Disitamab vedotin

Disitamab vedotin, a HER2-targeted antibody-drug conjugate, will be administered intravenously at 2 mg/kg on Day 1 of each 2-week cycle (Q2W). During the neoadjuvant phase, participants will receive 6 cycles in combination with toripalimab and the arm-specific sensitizing agent. Participants who achieve clinical complete response after cTURBT and comprehensive response assessment will receive an additional 6 cycles of disitamab vedotin plus toripalimab as consolidation therapy.

DRUG

Toripalimab

Toripalimab, an anti-PD-1 monoclonal antibody, will be administered intravenously at 3 mg/kg on Day 1 of each 2-week cycle (Q2W). During the neoadjuvant phase, participants will receive 6 cycles in combination with disitamab vedotin and the arm-specific sensitizing agent. Participants who achieve clinical complete response after cTURBT will receive 6 additional cycles of toripalimab plus disitamab vedotin consolidation therapy, followed by toripalimab maintenance therapy at 240 mg intravenously every 3 weeks (Q3W) for up to 1 year or until recurrence or study withdrawal.

DRUG

Sitagliptin

Sitagliptin phosphate, a DPP-4 inhibitor, will be administered orally at 100 mg once daily throughout the 6-cycle neoadjuvant treatment phase (approximately 3 months), in combination with disitamab vedotin and toripalimab.

DRUG

Zeprumetostat

Zeprumetostat, an EZH2 inhibitor, will be administered orally at 350 mg twice daily throughout the 6-cycle neoadjuvant treatment phase (approximately 3 months), in combination with disitamab vedotin and toripalimab.

DRUG

Tafolecimab

Tafolecimab, a PCSK9-targeting monoclonal antibody, will be administered by subcutaneous injection at 150 mg on Day 1 of each 2-week cycle (Q2W) for 6 neoadjuvant treatment cycles (approximately 3 months), in combination with disitamab vedotin and toripalimab.

DRUG

Ursodeoxycholic Acid

Ursodeoxycholic acid will be administered orally at 250 mg twice daily throughout the 6-cycle neoadjuvant treatment phase (approximately 3 months), in combination with disitamab vedotin and toripalimab.

PROCEDURE

Complete transurethral resection of bladder tumor

Complete transurethral resection of bladder tumor (cTURBT) will be performed within 6 weeks after completion of 6 cycles of neoadjuvant therapy in all study arms. The procedure will be combined with imaging assessment, pathological evaluation, and urine cytology to determine clinical response, including clinical complete response, and to guide subsequent bladder-preservation management or salvage radical cystectomy.

Sponsors & Collaborators

• First Affiliated Hospital of Chongqing Medical University

  collaborator OTHER

• Tianjin Medical University Second Hospital

  collaborator OTHER

• Peking University First Hospital

  collaborator OTHER

• Peking University People's Hospital

  collaborator OTHER

• The First Affiliated Hospital with Nanjing Medical University

  collaborator OTHER

• Shengjing Hospital

  collaborator OTHER

• Fujian Provincial Hospital Affiliated to Fuzhou University

  collaborator UNKNOWN

• Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University

  lead OTHER

Study Design

Allocation

NON_RANDOMIZED

Purpose

TREATMENT

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2026-07-01

Primary Completion

2028-06-30

Completion

2029-01-31

Countries

• China

Study Locations