Puxitatug Samrotecan (AZD8205) Monotherapy vs Chemotherapy in B7-H4-selected Endometrial Cancer (Bluestar-Endometrial01)

Not Applicable

Not yet recruiting

• Conditions: Endometrial Cancer; Malignant Solid Tumour
• Interventions: Drug: Puxitatug Samrotecan; Drug: Doxorubicin; Drug: Paclitaxel

• Registration Number: NCT07044336
• Lead Sponsor: AstraZeneca

Brief Summary

This is a Phase III, 2-arm, randomized, open label, multicenter, global study assessing the efficacy and safety of puxitatug samrotecan compared to physician's choice of chemotherapy (doxorubicin or paclitaxel) in participants with B7-H4 selected advanced/metastatic EC that progressed following platinum based chemotherapy and anti-PD-1/anti-PD-L1 therapy.

Detailed Description

The target population of interest in this study is participants with B7-H4-selected advanced/metastatic EC who have progressed on or after platinum-based chemotherapy and anti-PD-1/anti-PD-L1 therapy, either separately or in combination and should have received no more than 2 prior lines of therapy in advanced/metastatic setting. Participants will be randomized in a 1:1 ratio to AZD8205 (arm A) or physician's choice of chemotherapy (arm B; doxorubicin or paclitaxel). The total study size will be approximately 700 eligible participants.

During the treatment period, participants will receive AZD8205 IV Day 1 Q3W (Arm A) or either doxorubicin treatment IV Day 1 Q3W or paclitaxel treatment IV on Days 1, 8, and 15 in 28-day cycles (Arm B).

This study aims to see if puxitatug samrotecan allows participants to live longer without their endometrial cancer getting worse, or simply to live longer, compared to participants receiving standard of care chemotherapy. This study is also looking to see how the treatment and the endometrial cancer affects participants' quality of life.

Study Timeline

• Status Verified: 2025-06
• Study First Submitted: 2025-06-23
• Study First Submitted QC: 2025-06-23
• Last Update Submitted: 2025-06-23
• Study First Posted: 2025-06-30
• Last Update Posted: 2025-06-30
• Study Start: 2025-07-16
• Primary Completion: 2027-10-15
• Study Completion: 2028-03-16

Recruitment & Eligibility

• Status: NOT_YET_RECRUITING
• Sex: Female
• Target Recruitment: 700

Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Puxitatug Samrotecan	Puxitatug Samrotecan	P-Sam IV (intravenous) Q3W .
Chemotherapy	Doxorubicin	Physician's choice of chemotherapy Doxorubicin IV Q3W or Paclitaxel IV on Days 1, 8, and 15 in 28 day cycles.
Chemotherapy	Paclitaxel	Physician's choice of chemotherapy Doxorubicin IV Q3W or Paclitaxel IV on Days 1, 8, and 15 in 28 day cycles.

Primary Outcome Measures

Name	Time	Method
Progression Free Survival (PFS) for Arm A vs Arm B	Approximately 3 years	PFS is defined as the time from randomization until progression per RECIST 1.1 as assessed by BICR or death due to any cause.
Overall survival (OS) for Arm A vs Arm B	Approximately 3 years	OS is defined as the time from randomization until the date of death due to any cause.

Secondary Outcome Measures

Name	Time	Method
Assessment of Overall Response Rate (ORR) for Arm A vs Arm B	Approximately 3 years	ORR is defined as the proportion of participants who have a response of CR or PR, as determined by BICR assessments, per RECIST 1.1.
Assessment of Duration of response (DoR) for Arm A vs Arm B	Approximately 3 years	DoR will be defined as the time from the date of first documented response until the date of documented progression per RECIST 1.1 as assessed by BICR, or death due to any cause.
Assessment of progression-free survival 2 (PFS2) for Arm A vs Arm B	Approximately 3 years	PFS2 will be defined as the time from randomization to the earliest of the progression event (following the initial Investigator-assessed progression), after first subsequent therapy, or death.
Time until first subsequent anticancer therapy after discontinuation of the randomized treatment, or death (TFST) for Arm A vs Arm B	Approximately 3 years	TFST is defined as the time from randomization until the start date of the first subsequent anticancer therapy after discontinuation of the randomized treatment, or death due to any cause.
Time until the second subsequent anticancer therapy after discontinuation of the first subsequent treatment, or death (TSST) for Arm A vs Arm B	Approximately 3 years	TSST is defined as the time from randomization until the start date of the second subsequent anticancer therapy after discontinuation of the first subsequent treatment, or death due to any cause.
Time until discontinuation of treatment for any reason, or death (TDT) for Arm A vs Arm B	Approximately 3 years	TDT is defined as the time from randomization until discontinuation of treatment for any reason, including disease progression, toxicity, and death.
Worsening in endometrial symptoms for Arm A vs Arm B	Approximately 3 years	Time to worsening is defined as time from date of randomization to the date of worsening while on treatment for endometrial symptoms, physical functioning, and health-related quality of life based on select items from the EORTC IL389.