Giredestrant Shows Benefit for Early Breast Cancer in Phase 3 Trial

The phase 3 lidERA Breast Cancer study found that the investigational endocrine therapy giredestrant improved invasive disease-free survival for people with estrogen receptor-positive, HER2-negative early breast cancer compared with standard treatment, marking the first time a selective estrogen receptor degrader (SERD) has shown a significant benefit in the adjuvant setting, according to a news release from Roche.

“Today’s results underscore the potential of giredestrant as a new endocrine therapy of choice for people with early-stage breast cancer, where there is a chance for cure,” said Dr. Levi Garraway, Roche’s chief medical officer and head of Global Product Development, in the news release. “Given that ER-positive breast cancer accounts for approximately 70% of cases diagnosed, these findings — together with recent data in the advanced ER-positive setting — suggest that giredestrant has the potential to improve outcomes for many people with this disease.”

At the time of the interim analysis, overall survival data were still early, but researchers reported a clear positive trend. Giredestrant was generally well tolerated, and the side effects seen matched what is already known about the treatment, with no unexpected concerns. Full results from the lidERA study will be shared at an upcoming medical meeting and with health authorities to help move this potential option closer to patients.

Many people still face the possibility of recurrence during or after endocrine therapy for early-stage disease, and some need to interrupt or stop treatment early because of side effects, which can increase the risk of death. These challenges highlight the need for options that are both more effective and easier to tolerate, so patients can stay on treatment and reduce the chance of their cancer returning.

The lidERA study is the second late-stage trial of giredestrant to show positive results, following findings from the evERA study presented earlier this year. Earlier research in the neoadjuvant setting, including the coopERA trial, also showed that giredestrant reduced tumor cell growth more than an aromatase inhibitor. Altogether, the evidence suggests that giredestrant may improve outcomes compared with standard endocrine therapy for people with estrogen receptor-positive early-stage and advanced breast cancer, as per the release.

Study Design

The lidERA Breast Cancer study is a phase 3, randomized, open-label trial testing whether the adjuvant therapy giredestrant can work as safely and effectively as standard endocrine treatment for people with medium- or high-risk stage 1 through 3 estrogen receptor-positive, HER2-negative breast cancer. More than 4,100 patients enrolled in the study.

Researchers are focusing first on invasive disease-free survival, which in this study looks at the return or spread of breast cancer but does not count new, unrelated cancers in other organs. Other goals include tracking overall survival, a broader measure of invasive disease-free survival that does include second cancers outside the breast, disease-free survival and safety.

More Information of Giredestrant

Giredestrant is an investigational oral treatment designed to fully block and break down the estrogen receptor, which can slow or stop the growth of cancer cells that rely on estrogen. It is considered a next-generation selective estrogen receptor degrader.

Giredestrant is being studied across a large clinical program, including five phase 3 trials in different treatment settings to reach as many people as possible. These include studies comparing giredestrant with standard endocrine therapy as adjuvant treatment for estrogen receptor-positive, HER2-negative early breast cancer; giredestrant plus Afinitor (everolimus) for locally advanced or metastatic disease; giredestrant plus palbociclib versus letrozole plus palbociclib for recurrent locally advanced or metastatic disease; giredestrant combined with a cyclin-dependent kinase 4/6 inhibitor for advanced breast cancer that has become resistant to adjuvant endocrine therapy; and giredestrant with Phesgo (Perjeta [pertuzumab] plus Herceptin [trastuzumab]) for estrogen receptor-positive, HER2-positive locally advanced or metastatic breast cancer.

Reference

1. “[Ad hoc announcement pursuant to Art. 53 LR] Roche’s giredestrant becomes the first oral SERD to show superior invasive disease-free survival in early breast cancer,” Roche. News Release. Nov. 17, 2025.

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