The results of the EMPRESS study show the activity of giredestrant in reducing tumor proliferation in ER+/HER2- breast cancer at early stages without the need for ovarian function suppression

• The EMPRESS study analyzes the potential benefit of giredestrant, a potent oral selective estrogen receptor degrader (SERD), in premenopausal women with early-stage ER+/HER2- breast cancer. 
• The results, presented during the ESMO 2025 congress, indicate a significant reduction in tumor markers compared to the current standard therapy. 
• These findings pave the way for exploring endocrine therapy-based strategies in premenopausal women without the need for ovarian function suppression, improving the quality of life for women with this tumor type.

BERLIN, Oct. 20, 2025 /PRNewswire/ -- CMEDSIR, the leading international oncology research company, today announced the positive results of its EMPRESS study, conducted in collaboration with Roche Farma. This is an international, multicenter Phase II trial that evaluates the potential benefit of the drug giredestrant, a potent oral selective estrogen receptor degrader (SERD), in premenopausal women with early-stage ER+/HER2- breast cancer.

The results, presented at the congress during an oral session, demonstrated that giredestrant, administered as a single agent in the preoperative setting, shows greater activity compared to standard treatment with tamoxifen in slowing the proliferation of tumor cells. The study met its primary endpoint by showing that, after 15 days of treatment, patients receiving giredestrant experienced a significant reduction in the tumor proliferation marker Ki-67. This protein appears in cells when they are dividing, so its reduction indicates a positive response to treatment.

One of the most relevant findings of the study is that, for the first time, this reduction in tumor activity is achieved without suppressing the patient's ovarian function. This suggests that giredestrant could represent a more effective oral therapeutic alternative to the current standard therapy, with the potential to improve patients' quality of life by avoiding the adverse effects associated with ovarian suppression, which is typically performed with injections of luteinizing hormone-releasing hormone (LHRH) analogs.

"The results of the EMPRESS study are very promising, as they indicate greater activity of giredestrant compared to tamoxifen in slowing tumor proliferation, as measured by Ki-67," said Dr. Antonio Llombart-Cussac, principal investigator of the study, during the presentation. He also emphasized that "this study opens the door to exploring the potential use of giredestrant without ovarian function suppression in premenopausal women, which could significantly improve patients' quality of life by avoiding the side effects associated with traditional treatment."

Theranostics: The Revolution in Oncology

As part of the congress and its commitment to international collaboration and innovation, MEDSIR held a new edition of its MEDTalks forum in Berlin, supported by Telix Pharma. During the event, the company brought together leading national and international oncology experts, including Dr. Matthias Preusser (Medical University of Vienna), Dr. Nathalie Albert (Ludwig Maximilian University of Munich), Dr. Christophe Deroose (KU Leuven), and Dr. Jaume Capdevila (Vall d'Hebron Institute of Oncology, VHIO). The goal of this edition was to explore the crucial role of theranostics in optimizing cancer research.

Under the title "Understanding the Challenge in Clinical Trials," the discussion addressed the importance of implementing this new approach in oncology, which combines imaging-based diagnosis with precision therapy. This therapeutic strategy benefits patients in more advanced stages with limited treatment options through the administration of a radiopharmaceutical—first to visualize the tumor (diagnosis) and then to treat it (therapy).

MEDSIR Reinforces Its Commitment to Breast Cancer at ESMO 2025

In addition to the oral presentation of EMPRESS results, MEDSIR's active participation in the ESMO congress includes the poster presentation of the TELESCOPE study. This ongoing national phase II clinical trial, conducted in collaboration with pharmaceutical company Merck Sharp & Dohme, evaluates the addition of pembrolizumab to carboplatin and paclitaxel treatment during 12 weeks prior to surgery for patients with stage I triple-negative breast cancer. The goal is to assess the pathological complete response (pCR) rate to preoperative treatment.

ABOUT MEDSIR 

Established in 2012, MEDSIR prides itself on working closely with its strategic partners to drive innovation in oncology research. Operating in Spain and the United States, the company provides end-to-end clinical trial management, from study design to publication, with an extensive global network of experts and integrated technology to streamline the process. The company offers proof-of-concept support and a strategic approach that enables research partners to benefit from the best of both worlds: industry clinical research and investigator-driven trials.     

With the aim of promoting independent research worldwide, MEDSIR has formed a strategic alliance with Oncoclínicas, the leading oncology group in Brazil, which offers outstanding research potential in South America.  

For further information: www.medsir.org

SOURCE MEDSIR