NCT05296798

A Study to Evaluate the Efficacy and Safety of Giredestrant in Combination With Phesgo (Pertuzumab, Trastuzumab, and Hyaluronidase-zzxf) Versus Phesgo in Participants With Locally Advanced or Metastatic Breast Cancer (heredERA Breast Cancer)

A Phase III, Randomized, Open-Label Study Evaluating the Efficacy and Safety of Giredestrant in Combination With Phesgo Versus Phesgo After Induction Therapy With Phesgo + Taxane in Patients With Previously Untreated HER2-Positive, Estrogen Receptor-Positive Locally-Advanced or Metastatic Breast Cancer

• Status: Active Not Recruiting
• Phase: Phase 3
• Study type: Interventional
• Enrollment: 922 (estimated)
• Sponsor: Hoffmann-La Roche · Industry
• Sex: All
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

This Phase III, randomized, two-arm, open-label, multicenter study will evaluate the efficacy and safety of giredestrant plus Phesgo compared with Phesgo after induction therapy with Phesgo plus taxane in participants with human epidermal growth factor receptor 2 (HER2)-positive, estrogen receptor (ER)-positive advanced breast cancer (metastatic or locally advanced disease not amenable to curative treatment) who have not previously received a systemic non-hormonal anti-cancer therapy in the advanced setting.

Conditions

• Locally Advanced or Metastatic Breast Cancer

Interventions

Type	Name	Description
DRUG	Phesgo	Phesgo will be administered subcutaneously (SC) at a fixed non-weight-based dose. In the induction therapy phase, a loading dose (1200 milligram (mg) pertuzumab, 600 mg trastuzumab, and 30,000 units of recombinant human PH20 hyaluronidase \[rHuPH20\]) will be administered in the first cycle (1 cycle is 21 days). In subsequent cycles, maintenance doses (600 mg pertuzumab, 600 mg trastuzumab, and 20,000 units rHuPH20) will be administered once every 3 weeks (Q3W).
DRUG	Giredestrant	A 30 milligram (mg) capsule of giredestrant will be taken orally once a day on Days 1 to 21 of each 21-day cycle.
DRUG	Docetaxel	During the induction therapy phase, the investigator's choice of taxane-based chemotherapy (i.e., docetaxel or paclitaxel) will be administered after Phesgo. Docetaxel will be administered at 75 milligrams per metre squared of body surface area (mg/m2) intravenously over 60 (±10) minutes on Day 1 of each cycle for 4 to 8 cycles (a cycle is 21 days); this dose may be escalated to 100 mg/m2 if the initial dose was well tolerated.
DRUG	Paclitaxel	During the induction therapy phase, the investigator's choice of taxane-based chemotherapy (i.e., docetaxel or paclitaxel) will be administered after Phesgo. Paclitaxel will be administered at 80 milligrams per metre squared of body surface area (mg/m2) intravenously over a minimum of 1 hour on Days 1, 8, and 15 of each cycle for 4 to 8 cycles (a cycle is 21 days); this weekly regimen is considered as one complete cycle whenever 3 weekly doses are given.
DRUG	LHRH Agonist	A luteinizing hormone-releasing hormone (LHRH) agonist will be administered every 28 days to pre- and peri-menopausal women and all male participants while receiving giredestrant in Arm B. An LHRH agonist may be administered to male participants and pre- and peri-menopausal female participants receiving tamoxifen in Arm A, and should be administered to those receiving an aromatase inhibitor in Arm A. The investigator will determine and supply the appropriate LHRH agonist locally approved for use in breast cancer. The LHRH agonist will be administered according to local prescribing information.
DRUG	Optional Endocrine Therapy of Investigator's Choice	For participants in Arm A, optional endocrine therapy of investigator's choice is allowed based on the standard of care, and it can include an aromatase inhibitor or tamoxifen with or without an LHRH agonist, or gonadal ablation. The decision to include or exclude this option must be made prior to randomization.

Timeline

• Start date: 2022-07-18
• Primary completion: 2027-10-31
• Completion: 2030-12-31
• First posted: 2022-03-25
• Last updated: 2026-04-16

Locations

206 sites across 29 countries: United States, Argentina, Belgium, Brazil, China, Colombia, Egypt, France, Germany, Hungary, India, Italy, Jordan, Kenya, Lebanon, Mexico, Oman, Poland, Portugal, Saudi Arabia, South Africa, South Korea, Spain, Taiwan, Thailand, Turkey (Türkiye), Uganda, United Arab Emirates, United Kingdom

Regulatory

• FDA-regulated drug study