SONIA

NCT03425838 📎

Regimen

Experimental
Strategy A: 1L nonsteroidal AI plus CDK4/6 inhibitor (investigator choice), then 2L fulvestrant at progression.
Control
Strategy B: 1L nonsteroidal AI alone, then 2L fulvestrant plus CDK4/6 inhibitor at progression.

Population

Postmenopausal women with HR+/HER2- advanced breast cancer, treatment-naive for metastatic disease, randomized to 1L vs 2L use of a CDK4/6 inhibitor.

Key finding

SONIA tested 1L vs 2L CDK4/6 strategy in HR+/HER2- metastatic disease and found no significant PFS2 or OS benefit from routine 1L use over reserving CDK4/6 for 2L. Toxicity and cost were substantially lower in the 2L strategy, challenging the assumption that 1L CDK4/6 is universally preferred.

Source: PMID 39604725

Timeline

  • Publication: 2024 Dec

Guideline citations

  • NCCN BREAST