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A Study to Compare DB-1303/BNT323 Versus T-DM1 in Breast Cancer

Phase 3
Recruiting
Conditions
HER2-positive Breast Cancer
Interventions
Drug: DB-1303/BNT323
Registration Number
NCT06265428
Lead Sponsor
DualityBio Inc.
Brief Summary

This study is designed to compare efficacy and safety of DB-1303/BNT323 versus T-DM1 in HER2-positive, unresectable and/or metastatic breast cancer patients previously treated with trastuzumab and taxane.

Detailed Description

This is a randomized controlled, 2-arm, open-label, multicenter phase III study to assess the efficacy and safety of DB-1303/BNT323 versus Trastuzumab Emtansine (T-DM1) in patients with human epidermal growth factor receptor 2 (HER2) -positive unresectable/metastatic breast cancer who have been treated with trastuzumab and taxanes. Approximately 224 patients with unresectable or metastatic HER2-positive breast cancer will be randomized 1:1 to receive DB-1303/BNT323 or T-DM1, respectively.

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
224
Inclusion Criteria
  • Male or female adults ≥ 18 years at the time of voluntary signing of informed consent.
  • Pathologically confirmed unresectable or metastatic HER2 positive breast cancer previously treated with trastuzumab and taxane
  • Eastern Cooperative Oncology Group (ECOG) performance status score is 0 or 1.
  • Presence of at least one measurable lesion according to RECIST v1.1
  • Expected survival time ≥ 12 weeks.
  • Patients must give informed consent to this study and voluntarily sign written informed consent form prior to the study.
Exclusion Criteria
  • Prior anti-HER2 ADC therapy.
  • Previous history of interstitial lung disease/noninfectious pneumonitis/radiation pneumonitis requiring steroid therapy.
  • Known serious hypersensitivity to the active ingredients of the study drug, inactive ingredients in the formulation, or other antibody drugs.
  • Multiple primary malignancies within 3 years, except for adequately resected non-melanoma skin cancer, curatively treated in situ tumor, or contralateral breast cancer
  • Uncontrolled infection requiring intravenous antibiotics, antiviral or antifungal agents, autoimmune disease requiring treatment, uncontrolled diabetes, hypertension, or other systemic disease that makes compliance with study procedures difficult
  • Unrecovered toxicity from prior anticancer therapy, defined as toxicity (except for alopecia) not recovered to ≤Grade 1 (NCI-CTCAE v5.0) or baseline.

NOTE: Other protocol defined Inclusion/Exclusion criteria may apply.

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
DB-1303/BNT323DB-1303/BNT323Enrolled patients will receive DB-1303/BNT323 by intravenous (I.V.) infusion
T-DM1T-DM1Enrolled patients will receive T-DM1 by I.V. infusion
Primary Outcome Measures
NameTimeMethod
Progression Free Survival (PFS) by Blinded Independent Central Review (BICR) assessment per Response Evaluation Criteria in Solid Tumors Version 1.1 (RECIST 1.1)Up to approximately 24 months.

Defined as the time from randomization to the first documented disease progression per RECIST 1.1 as assessed by BICR or death due to any cause, whichever occurs first

Secondary Outcome Measures
NameTimeMethod
Progression Free Survival (PFS) by Investigator assessment per RECIST 1.1Up to approximately 24 months.

Defined as the time from randomization to the first documented disease progression per RECIST 1.1 as assessed by investigator or death due to any cause, whichever occurs first.

PK parameters: maximum observed concentration (Cmax)Up to approximately 24 months.

Maximum observed concentration (Cmax) of DB-1303/BNT323 Antibody-drug conjugate (ADC) and free toxin P1003, etc. after DB-1303/BNT323 administration

Overall Survival (OS)Up to approximately 24 months.

Defined as the time from randomization to death due to any cause.

Objective response rate (ORR) by BICR and investigator assessment per RECIST 1.1Up to approximately 24 months.

Defined as the percentage of patients who have a complete response (CR) or partial response (PR) per RECIST 1.1 as assessed by BICR and investigator assessment.

Adverse events (AEs)Up to approximately 24 months.

Number and percentage of patients who report serious adverse events (SAEs), treatment-emergent adverse events (TEAEs), TEAEs leading to study drug discontinuation, adverse events of special interest (AESIs) (graded according to the National Cancer Institute Common Terminology Criteria for Adverse Events version 5.0\[NCI-CTCAE v5.0\])

Patient reported outcomes (PROs): EORTC QLQ-BR45Up to approximately 24 months.

Change from baseline in the functioning/symptom subscales of EORTC QLQ-BR45. Scale scores range from 0-100. For functioning scales, higher scores indicate better functioning. For symptom scales, higher scores indicate greater symptom burden.

Duration of response (DoR) by BICR and investigator assessment per RECIST 1.1Up to approximately 24 months.

Defined as the time from first response (CR or PR) to subsequent disease progression per RECIST 1.1 as assessed by BICR and investigator assessment, or death from any cause, whichever occurs first.

PK parameters: time to maximum concentration (Tmax)Up to approximately 24 months.

Time to maximum concentration (Tmax) of DB-1303/BNT323 ADC and free toxin P1003, etc. after DB-1303/BNT323 administration

Patient reported outcomes (PROs): European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire (QLQ) - C30Up to approximately 24 months.

Change from baseline in the functioning/symptom/global quality of life (QoL) subscales of EORTC QLQ-C30. Scale scores range from 0-100. For functioning and global QoL scales, higher scores indicate better functioning or global health status. For symptom scales, higher scores indicate greater symptom burden.

Patient reported outcomes (PROs): European Quality of Life Five Dimension Five Level Scale (EQ-5D-5L)Up to approximately 24 months.

Change from baseline in EQ-5D-5L health state utility index score and Visual Analogue Scale (VAS) score. VAS score range from 0-100, higher scores indicate better health status.

European Quality of Life Five Dimension Five Level Scale (EQ-5D-5L)Up to approximately 24 months.

EQ-5D-5L health state utility index score and Visual Analogue Scale (VAS) score. The change from baseline value will be reported.

Anti-drug antibodies (ADA)Up to approximately 24 months.

Number and percentage of patients who develop anti-drug antibody (ADA) for DB-1303/BNT323.

Trial Locations

Locations (48)

015

🇨🇳

Bengbu, Anhui, China

029

🇨🇳

Hefei, Anhui, China

001

🇨🇳

Beijing, Beijing, China

010

🇨🇳

Beijing, Beijing, China

038

🇨🇳

Jilin, Changchun, China

037

🇨🇳

Xiamen, Fujian, China

048

🇨🇳

Shijiazhuang, Hebei, China

020

🇨🇳

Haerbin, Heilongjiang, China

016

🇨🇳

Hefei, Anhui, China

036

🇨🇳

Fuzhou, Fujian, China

023

🇨🇳

Guangzhou, Guangdong, China

024

🇨🇳

Guangzhou, Guangdong, China

026

🇨🇳

Guangzhou, Guangdong, China

028

🇨🇳

Huizhou, Guangdong, China

017

🇨🇳

Nanning, Guangxi, China

022

🇨🇳

Nanning, Guangxi, China

005

🇨🇳

Zhengzhou, Henan, China

043

🇨🇳

Haikou, Hainan, China

045

🇨🇳

Baoding, Hebei, China

011

🇨🇳

Wuhan, Hubei, China

018

🇨🇳

Luoyang, Henan, China

006

🇨🇳

Zhengzhou, Henan, China

009

🇨🇳

Wuhan, Hubei, China

030

🇨🇳

Changsha, Hunan, China

027

🇨🇳

Nanjing, Jiangsu, China

004

🇨🇳

Nanjing, Jiangsu, China

044

🇨🇳

Xuzhou, Jiangsu, China

014

🇨🇳

Nanchang, Jiangxi, China

008

🇨🇳

Changchun, Jilin, China

032

🇨🇳

Dalian, Liaoning, China

040

🇨🇳

Binzhou, Shandong, China

031

🇨🇳

Jinan, Shandong, China

047

🇨🇳

Jinan, Shandong, China

012

🇨🇳

Linyi, Shandong, China

039

🇨🇳

Yantai, Shandong, China

002

🇨🇳

Shanghai, Shanghai, China

046

🇨🇳

Shanghai, Shanghai, China

035

🇨🇳

Taiyuan, Shanxi, China

003

🇨🇳

Xi'an, Shanxi, China

007

🇨🇳

Chengdu, Sichuan, China

041

🇨🇳

Neijiang, Sichuan, China

034

🇨🇳

Yibin, Sichuan, China

021

🇨🇳

Tianjin, Tianjin, China

013

🇨🇳

Ürümqi, Xinjiang, China

033

🇨🇳

Kunming, Yunnan, China

019

🇨🇳

Hangzhou, Zhejaing, China

025

🇨🇳

Hangzhou, Zhejiang, China

042

🇨🇳

Hangzhou, Zhejiang, China

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