Investigational Drug Information for Giredestrant

What is the drug development status for Giredestrant?

Giredestrant is an investigational drug.

There have been 19 clinical trials for Giredestrant. The most recent clinical trial was a Phase 1 trial, which was initiated on January 27^th 2025.

The most common disease conditions in clinical trials are Breast Neoplasms, Endometrial Neoplasms, and [disabled in preview]. The leading clinical trial sponsors are Hoffmann-La Roche, Genentech, Inc., and MedSIR.

There are thirty-nine US patents protecting this investigational drug and thirty-one international patents.

Summary for Giredestrant

US Patents	39
International Patents	31
US Patent Applications	152
WIPO Patent Applications	128
Japanese Patent Applications	18
Clinical Trial Progress	Phase 1 (2025-01-27)
Vendors	28

Recent Clinical Trials for Giredestrant

Title	Sponsor	Phase
A Study to Evaluate the Safety, Pharmacokinetics, and Activity of GDC-0587 as a Monotherapy and in Combination With Giredestrant in Participants With Locally Advanced or Metastatic Estrogen Receptor-Positive and Human Epidermal Growth Factor Rec	Genentech, Inc.	PHASE1
A Study to Evaluate the Effect of GDC-4198 Alone and in Combination With Giredestrant Versus Abemaciclib and Giredestrant in Participants With Locally Advanced or Metastatic Estrogen Receptor-Positive (ER+), Human Epidermal Growth Factor Recepto	Roche (China) Holding Ltd.	PHASE1
A Study to Evaluate the Effect of GDC-4198 Alone and in Combination With Giredestrant Versus Abemaciclib and Giredestrant in Participants With Locally Advanced or Metastatic Estrogen Receptor-Positive (ER+), Human Epidermal Growth Factor Recepto	Genentech, Inc.	PHASE1

See all Giredestrant clinical trials

Clinical Trial Summary for Giredestrant

Top disease conditions for Giredestrant

Top clinical trial sponsors for Giredestrant

See all Giredestrant clinical trials

US Patents for Giredestrant

Drugname	Patent Number	Patent Title	Patent Assignee	Estimated Expiration
Giredestrant		Solid forms of 3-((1R,3R)-1-(2,6-difluoro-4-((1-(3- fluoropropyl)azetidin-3-yl)amino)phenyl)-3-methyl-1,3,4,9-tetrahydro-2H-pyrido[3,4-b]indol-2-yl)-2,2-difluoropropan-1-ol and processes for preparing fused tricyclic compounds comprising a substituted phenyl or pyridinyl moiety, including methods of their use	Hoffmann La Roche Inc
Giredestrant		Tetrahydro-pyrido[3,4-b]indole estrogen receptor modulators and uses thereof	Genentech Inc
Giredestrant		Diagnostic and therapeutic methods for the treatment of breast cancer	F Hoffmann La Roche AG

International Patents for Giredestrant

Drugname	Country	Document Number	Estimated Expiration	Related US Patent
Giredestrant	Argentina	AR103081	2034-12-18
Giredestrant	Australia	AU2015367509	2034-12-18
Giredestrant	Australia	AU2020200407	2034-12-18

Giredestrant: Development Status and Market Outlook

Last updated: February 19, 2026

Giredestrant, a novel oral selective estrogen receptor degrader (SERD), is undergoing clinical development for estrogen receptor-positive (ER+), human epidermal growth factor receptor 2-negative (HER2-) advanced or metastatic breast cancer. The drug’s efficacy is being evaluated in monotherapy and in combination with other targeted agents. Clinical trial data and ongoing regulatory pathways indicate potential market entry within the next three to five years, targeting a significant segment of the breast cancer patient population with unmet needs in endocrine resistance.

What is the current development status of Giredestrant?

Giredestrant is currently in Phase III clinical development. The pivotal Phase III trial, EMERALD1 (NCT04432027), is evaluating giredestrant plus the PI3K inhibitor taselisib compared to standard endocrine therapy. This trial focuses on postmenopausal women with ER+/HER2- advanced breast cancer who have progressed on at least one prior endocrine therapy. Data from earlier Phase I/II trials have informed the design of the ongoing Phase III program.

• Phase I/II Trials: Early-phase studies (e.g., NCT03144372) demonstrated a manageable safety profile for giredestrant and preliminary signs of efficacy, supporting its progression to later-stage development. These trials established dose ranges and identified patient populations most likely to benefit.
• Phase III Trials:
  • EMERALD1: This is the primary Phase III trial for giredestrant. It is a randomized, double-blind, controlled study comparing giredestrant in combination with taselisib to physician's choice of standard endocrine therapy. The primary endpoint is progression-free survival (PFS). The trial has enrolled a substantial number of patients globally.
  • EMERALD2 & EMERALD3: Companion trials are investigating giredestrant in different combinations and patient populations, including those with specific genetic mutations (e.g., ESR1 mutations) and in earlier lines of therapy. EMERALD2 (NCT04701003) is a Phase III trial of giredestrant plus palbociclib versus endocrine therapy plus palbociclib in first-line advanced ER+/HER2- breast cancer. EMERALD3 (NCT04657871) is a Phase II trial evaluating giredestrant in combination with venetoclax in patients with ER+/HER2- advanced breast cancer with a history of endocrine resistance.
• Regulatory Filings: Based on positive interim or final data from these trials, Roche (the developer) intends to submit regulatory applications to health authorities, including the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA). Target dates for these submissions are anticipated following the completion of data analysis from the ongoing Phase III studies.

What is the proposed mechanism of action for Giredestrant?

Giredestrant is an oral SERD designed to selectively bind to and degrade the estrogen receptor (ER). Unlike selective estrogen receptor modulators (SERMs) which can have mixed agonist and antagonist effects, SERDs like giredestrant aim to achieve complete blockade of ER signaling by promoting its degradation. This mechanism is particularly relevant in ER+ breast cancer, where the ER pathway drives tumor growth.

• Estrogen Receptor Degradation: Giredestrant binds to the ER, inducing a conformational change that targets the receptor for ubiquit}+...