NCT07288359

Study of GVV858 as a Single Agent or in Combination With Endocrine Therapy in Patients With HR+/HER2- Breast Cancer and Other Advanced Solid Tumors

An Open-label, Multi-center, Phase I/II Study of GVV858 as a Single Agent and in Combination With Endocrine Therapy in Patients With Advanced Hormone Receptor Positive, HER2- Negative Breast Cancer and Other Advanced Solid Tumors

• Status: Recruiting
• Phase: Phase 1 / Phase 2
• Study type: Interventional
• Enrollment: 205 (estimated)
• Sponsor: Novartis Pharmaceuticals · Industry
• Sex: All
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

Phase I: Characterize safety and tolerability of GVV858 as a single agent and in combination with fulvestrant or letrozole. Identify dose range for optimization/recommended dose for further clinical evaluation. Phase II: Further characterize the safety and tolerability of GVV858 in combination with fulvestrant in patients with hormone receptor-positive/human epidermal growth factor receptor 2-negative (HR+/HER2-) advanced breast cancer.

Detailed description

This is a first-in-human, open-label, phase I/II, multi-center study consisting of a GVV858 single agent treatment arm in patients with advanced HR+/HER2- breast cancer, other advanced solid tumors harboring CCNE1 amplification, and metastatic castration-resistant prostate cancer, and a combination treatment arm of GVV858 with fulvestrant or letrozole in patients with advanced HR+/HER2- breast cancer. Single agent escalation may be followed by an expansion part stratified by disease indication. The escalation of the fulvestrant combination arm may continue into a randomized, open label, Phase II with optional dose optimization in advanced HR+/HER2- breast cancer patients.

Conditions

• Advanced HR+/HER2- Breast Cancer
• Advanced CCNE1-amplified Solid Tumors
• Metastatic Castration-resistant Prostate Cancer

Interventions

Type	Name	Description
DRUG	GVV858	Experimental
DRUG	Fulvestrant	Approved medication
DRUG	Letrozole	Approved medication

Timeline

• Start date: 2025-12-29
• Primary completion: 2031-04-24
• Completion: 2031-05-09
• First posted: 2025-12-17
• Last updated: 2026-02-23

Locations

4 sites across 4 countries: United States, Japan, Singapore, Taiwan

Regulatory

• FDA-regulated drug study