A Phase I Study of RGT-419B in Patients With HR-Positive, HER2-Negative Advanced Breast Cancer or Other Solid Tumors

Phase 1

Active, not recruiting

• Conditions: Breast Cancer; Advanced Solid Tumor
• Interventions: Drug: RGT-419B

• Registration Number: NCT06299124
• Lead Sponsor: Regor Pharmaceuticals Inc.

Brief Summary

This is a Phase 1 dose escalation and dose expansion phase I study to evaluate the safety, tolerability, pharmacokinetic profile and preliminary efficacy of RGT-419B as monotherapy in Chinese patients with HR+/HER2- advanced/metastatic breast cancer and other advanced solid tumors.

Detailed Description

Not available

Study Timeline

• Study Start: 2023-04-17
• Study First Submitted: 2024-03-01
• Study First Submitted QC: 2024-03-01
• Study First Posted: 2024-03-07
• Status Verified: 2025-01
• Last Update Submitted: 2025-01-16
• Last Update Posted: 2025-01-20
• Primary Completion: 2025-07-30
• Study Completion: 2025-07-30

Recruitment & Eligibility

• Status: ACTIVE_NOT_RECRUITING
• Sex: All
• Target Recruitment: 40

Inclusion Criteria

• Male or female ≥ 18 years of age
• Eastern Cooperative Oncology Group (ECOG) performance status score of 0 or 1
• Subjects with pathologically confirmed advanced solid tumors who have failed standard-of-care therapy, or have no standard-of-care therapy available, or are currently not eligible for standard-of-care therapy; Subjects with HR+/ HER2- advanced or metastatic breast cancer are preferred.
• Estimated life expectancy of at least 12 weeks

Exclusion Criteria

• Presence of visceral metastases with severe organ dysfunction
• Known active hepatitis B or C infection
• Prior irradiation to >25% of the bone marrow and/or inadequate bone marrow function or evidence of clinicallysignificant end-organ damage
• History of allergic reactions attributed to compounds of similar chemical or biologic composition to the drugs usedin the study

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
RGT-419B monotherapy	RGT-419B	Dose escalation and dose expansion of RGT-419B monotherapy

Primary Outcome Measures

Name	Time	Method
Safety & Tolerability - Number of subjects with Dose-Limiting Toxicities (DLTs) at each cohort dose level	4 weeks (1 cycle)	Number of subjects who have a confirmed DLT at each cohort dose level during the first 28-day cycle of RGT-419B treatment.

Secondary Outcome Measures

Name	Time	Method
Day 1 and steady-state pharmacokinetics(PK) assessment of RGT-419B and major metabolites - Cmax	4 weeks (1 cycle)
Safety & Tolerability - Incidence, Severity, and Causality of all Treatment Emergent Adverse Events (TEAEs)	through study completion, an average of 1 year	Incidence, severity, and causality of all TEAEs will be assessed for all patients participating from Day 1 dosing through end of study.
Day 1 and steady-state PK assessment of RGT-419B and major metabolites - Area Under Concentration-TimeCurve to Infinity (AUC0-inf)	4 weeks (1 cycle)
Day 1 and steady-state PK assessment of RGT-419B and major metabolites - Accumulation rate after multipledoses	4 weeks (1 cycle)
Day 1 and steady-state PK assessment of RGT-419B and major metabolites - Plasma Decay Half-Life (t1/2)	4 weeks (1 cycle)
Day 1 and steady-state PK assessment of RGT-419B and major metabolites - Time to Reach Maximum ObservedPlasma Concentration (Tmax)	4 weeks (1 cycle)
Day 1 and steady-state PK assessment of RGT-419B and major metabolites - Cumulative urinary excretion	4 weeks (1 cycle)
Tumor Response assessed by Investigator according to RECIST v1.1	through study completion, an average of 1 year
QTc Interval - Changes in corrected QT interval	through study completion, an average of 1 year	Number of subjects with a clinically significant increase from baseline in corrected QT (QTc) interval onrepeated ECGs

Trial Locations

Locations (1)

Fudan University Shanghai Cancer Center; 🇨🇳 Shanghai, Shanghai, China