FDA Accepts New Drug Application for Genentech's Giredestrant in ESR1-Mutated, ER-Positive Advanced Breast Cancer

Giredestrant plus everolimus could be the first and only oral selective estrogen receptor degrader (SERD) combination approved in the post-cyclin-dependent kinase (CDK)4/6 inhibitor setting.

Published on Feb. 27, 2026

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Genentech, a member of the Roche Group, announced that the U.S. Food and Drug Administration (FDA) has accepted the company's New Drug Application for giredestrant, an investigational oral therapy, in combination with everolimus for the treatment of adult patients with estrogen receptor (ER)-positive, human epidermal growth factor receptor 2-negative, ESR1-mutated locally advanced or metastatic breast cancer following recurrence or progression on a prior endocrine-based regimen.

Why it matters

ER-positive breast cancer accounts for approximately 70% of breast cancer cases. Resistance to endocrine therapies, particularly in the post-CDK inhibitor setting, increases the risk of disease progression and is associated with poor outcomes. Oral combination therapies, such as giredestrant plus everolimus, could address this by targeting two different signaling pathways while helping to minimize the impact of treatment on people's lives without the need for injections.

The details

The filing acceptance is based on the Phase III evERA Breast Cancer study results, which showed that giredestrant plus everolimus reduced the risk of disease progression or death by 44% and 62% in the intention-to-treat (ITT) and ESR1-mutated populations, respectively, compared with standard-of-care endocrine therapy plus everolimus. In the ESR1-mutated population, the median progression-free survival (PFS) was 9.99 months compared with 5.45 months in the giredestrant and comparator arm, respectively. In the ITT population, the median PFS was 8.77 months compared with 5.49 months in the giredestrant and comparator arms, respectively.

  • The FDA is expected to make a decision on the approval by December 18, 2026.
  • The persevERA readout in first-line ER-positive breast cancer is expected in the first half of this year.

The players

Genentech

A leading biotechnology company that discovers, develops, manufactures and commercializes medicines to treat patients with serious and life-threatening medical conditions. Genentech is a member of the Roche Group.

Levi Garraway, M.D., Ph.D.

Chief medical officer and head of Global Product Development at Genentech.

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What they’re saying

“The clinically meaningful benefit seen with giredestrant could enable an important new treatment option to help delay disease progression or death in people with advanced, ER-positive breast cancer.”

— Levi Garraway, M.D., Ph.D., Chief medical officer and head of Global Product Development (Genentech)

What’s next

In the coming weeks, Genentech will submit the giredestrant Phase III lidERA data in early-stage breast cancer to the FDA.

The takeaway

This acceptance marks a first step towards establishing the giredestrant combination as a new standard of care in the treatment of estrogen receptor-positive, advanced breast cancer, particularly for patients with ESR1 mutations who have limited options after progressing on prior therapies.