HR+ Disease / SABCS 01/13/2026

SABCS 2025 Updates on Inavolisib and Giredestrant in Breast Cancer

A professional young man in a suit smiling in an office setting, representing healthcare, medical updates, or professional services. Tyler Kristoff, MD OncUpdates medical news and updates, featuring healthcare professionals, cancer research, treatment advancements, and oncology innovations for healthcare providers and patients. Sarah Premji, MD

Key Points

  • The INAVO120 trial found that the addition of inavolisib to first-line therapy improved overall survival (OS) for PIK3CA-mutated, HR-positive, HER2-negative, endocrine-resistant advanced breast cancer.
  • Giredestrant, an oral selective estrogen receptor degrader (SERD), was associated with better outcomes versus conventional endocrine therapies in the lidERA study.
  • Oral SERDs are a novel alternative to standard endocrine therapies and may further evolve the adjuvant treatment paradigm following recent approvals of CDK4/6 inhibitors.

INAVO120 and lidERA Data at SABCS 2025

Tyler Kristoff, MD, of Emory University, and Sarah Premji, MD, of Sarah Cannon Research Institute,   discussed recent updates in HR-positive breast cancer, including first-line inavolisib in advanced breast cancer and adjuvant giredestrant in early breast cancer, at the 2025 San Antonio Breast Cancer Symposium (SABCS 2025).

The discussion began with findings from the INAVO120 trial that evaluated the addition of inavolisib to palbociclib and fulvestrant in first-line treatment for patients with PIK3CA-mutated, HR-positive, HER2-negative, endocrine-resistant advanced breast cancer. Navolisib improved median OS to 34 months (95% CI, 28.4-44.8) compared with 27 months (95% CI, 22.8-38.7) in the control arm (stratified HR, 0.67; 95% CI, 0.49-0.94; P = .0190). These data support a change in clinical practice, according to Dr. Premji, who added that they place even greater emphasis on molecular profiling to identify patients with PIK3CA alterations.

In the lidERA trial on adjuvant breast cancer treatment, the oral SERD giredestrant showed superior invasive disease-free survival (IDFS) versus standard-of-care endocrine therapy (HR, 0.70; 95% CI, 0.57-0.87; P = .0014), according to the SABCS 2025 presentation. The 3-year IDFS rates were 92.4% and 89.6%, respectively. Giredestrant and other oral SERDs represent a promising alternative to conventional endocrine therapy. However, more research is needed to determine how best to incorporate them with existing treatments, particularly given that adjuvant CDK4/6 inhibitors have shown an OS benefit, Dr. Premji said.