NCT06340568

A Clinical Study of the Anti-cancer Effects of an Investigational Therapy or Chemotherapy in Patients With Recurring Uterine Cancer

A Phase III, Randomized, Multi-site, Open-label Trial of BNT323/DB-1303 Versus Investigator's Choice of Chemotherapy in Previously Treated Patients With HER2- Expressing Recurrent Endometrial Cancer

• Status: Recruiting
• Phase: Phase 3
• Study type: Interventional
• Enrollment: 480 (estimated)
• Sponsor: BioNTech SE · Industry
• Sex: Female
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

The study is divided into two cohorts (Cohort 1 and Cohort 2), to which participants will be enrolled based on the amount of human epidermal growth factor receptor 2 (HER2) in their tumor sample. In Cohort 1, the main goal is to assess how well BNT323 (also known as DB-1303) or chemotherapy (doxorubicin or paclitaxel \[or docetaxel, if participants cannot take paclitaxel\]) works by determining the progression-free survival (PFS) of participants who have been previously treated with immune checkpoint inhibitors (ICIs). In Cohort 2, the main goal is to assess how well BNT323 works by determining the objective response rate (ORR), that is, the percentage of participants whose tumor shrinks (partial response) or disappears (complete response) after treatment. The safety of BNT323 will also be assessed by following the occurrence of unfavorable/adverse effects that are seen after treatment. Other measures include the pharmacokinetics of BNT323 (or how BNT323 moves through and out of the body), the body's immune response, and the impact on quality of life.

Detailed description

This is an open-label, randomized, multi-site, Phase III, interventional clinical study designed to determine the efficacy and safety of BNT323 compared with investigator's choice of single agent chemotherapy in previously treated participants with recurrent endometrial cancer (including HER2 1+ or 2+ score as determined using a centralized immunohistochemistry \[IHC\] analysis method), whose disease has progressed on at least one line of platinum-based therapy and ICI (Cohort 1). In addition, participants with recurrent endometrial cancer with HER2 IHC 3+ score will be enrolled in a BNT323 monotherapy arm (Cohort 2) to further investigate the efficacy and safety of BNT323. In Cohort 1, participants will be randomized 2:1 to receive either BNT323/DB-1303 or investigator's choice of single agent chemotherapy, preferably doxorubicin or paclitaxel (or docetaxel if contraindicated to paclitaxel and available at the site) until Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST v1.1) defined progressive disease (PD) unless there is unacceptable toxicity, withdrawal of consent, or another criterion for discontinuation is met. In Cohort 2, participants will receive BNT323 monotherapy until RECIST v1.1 defined PD unless there is unacceptable toxicity, withdrawal of consent, or another criterion for discontinuation is met. The study consists of a screening period, a treatment period, a safety follow-up period, an efficacy follow-up period, and a long-term survival follow-up. The expected treatment duration per participant is \~6 months, followed by an anticipated long-term survival follow-up period of up to 53 months.

Conditions

• Endometrial Cancer

Interventions

Type	Name	Description
DRUG	BNT323/DB-1303	intravenous (IV) infusion
DRUG	Doxorubicin	IV bolus or infusion
DRUG	Paclitaxel	IV infusion
DRUG	Docetaxel	IV infusion

Timeline

• Start date: 2025-06-10
• Primary completion: 2028-03-01
• Completion: 2029-11-01
• First posted: 2024-04-01
• Last updated: 2026-03-31

Locations

112 sites across 18 countries: United States, Argentina, Australia, Belgium, Brazil, Canada, China, Czechia, Denmark, Finland, France, Israel, Italy, Netherlands, South Korea, Sweden, Taiwan, United Kingdom

Regulatory

• FDA-regulated drug study