NCT05296746: RIBOLARIS

Neoadjuvant and Adjuvant Ribociclib and ET for Clinically High-risk ER+ and HER2- Breast Cancer

Active, enrolled Phase 2 Last updated 18 March 2025

What this trial tests

Phase 2 trial testing Ribociclib (neoadjuvant) in Breast Cancer Stage II in 1,100 participants. Participants enrolled and being followed up; not accepting new ones.

Timeline

3 May 2022

Primary endpoint
1 October 2029

1 December 2031

Quick facts

Lead sponsor	SOLTI Breast Cancer Research Group
Phase	Phase 2
Status	Active, enrolled
Study type	INTERVENTIONAL
Allocation	non randomized
Design	parallel
Masking	none
Primary purpose	treatment
Enrollment	1,100
Start date	3 May 2022
Primary completion	1 October 2029
Estimated completion	1 December 2031
Sites	51 locations across France, Spain, Portugal

Drugs / interventions tested

• Ribociclib (neoadjuvant) — full drug profile →
• Chemotherapy (adjuvant) — full drug profile →
• Ribociclib (adjuvant) — full drug profile →

Conditions studied

• Breast Cancer Stage II — all drugs for Breast Cancer Stage II →

Sponsor

SOLTI Breast Cancer Research Group

Who can join

18 and older, any sex, with Breast Cancer Stage II. Patients with the condition only — healthy volunteers not accepted.

Sponsor's own description

This is an open-label, multicenter international trial in men and women with primary operable HR+/HER2-, ki67≥20%, grade 2 or 3 and stage II breast cancer to evaluate safety and long-term efficacy of a non-chemo treatment in patients biologically responders to neoadjuvant ribociclib and letrozole.

This study aims to evaluate whether chemotherapy could be avoided for initial high-risk clinicopathological breast cancer patients that are converted to low genomic risk assessed by Risk of Recurrence-low (ROR-low) at 6 months of letrozole - ribociclib neoadjuvant treatment by continuing with this treatment in adjuvant setting.

Publications & conference data

8 peer-reviewed publications reference this trial (live from Europe PMC):

1. Rationale and trial design of NATALEE: a Phase III trial of adjuvant ribociclib + endocrine therapy <i>versus</i> endocrine therapy alone in patients with HR+/HER2- early breast cancer.
   Slamon DJ, Fasching PA, Hurvitz S, Chia S, et al · · 2023 · cited 83× · PMID 37275963 · DOI 10.1177/17588359231178125
2. Cell-cycle inhibition and immune microenvironment in breast cancer treated with ribociclib and letrozole or chemotherapy.
   Pascual T, Fernandez-Martinez A, Agrawal Y, Pfefferle AD, et al · · 2024 · cited 14× · PMID 38448600 · DOI 10.1038/s41523-024-00625-7
3. The Evolving Pathways of the Efficacy of and Resistance to CDK4/6 Inhibitors in Breast Cancer.
   Gomes I, Abreu C, Costa L, Casimiro S. · · 2023 · cited 12× · PMID 37835528 · DOI 10.3390/cancers15194835
4. Identifying predictors of treatment response and molecular changes induced by neoadjuvant chemotherapy and endocrine therapy in hormone receptor-positive/HER2-negative breast cancer: the NEOENDO translational study.
   Schettini F, Brasó-Maristany F, Pascual T, Lorman-Carbó N, et al · · 2024 · cited 11× · PMID 39608304 · DOI 10.1016/j.esmoop.2024.103989
5. Gene Expression Assays to Tailor Adjuvant Endocrine Therapy for HR+/HER2- Breast Cancer.
   Bottosso M, Miglietta F, Vernaci GM, Giarratano T, et al · · 2024 · cited 8× · PMID 38656833 · DOI 10.1158/1078-0432.ccr-23-4020
6. Docetaxel Resistance in Breast Cancer: Current Insights and Future Directions.
   Postigo-Corrales F, Beltrán-Videla A, Lázaro-Sánchez AD, Hurtado AM, et al · · 2025 · cited 5× · PMID 40806254 · DOI 10.3390/ijms26157119
7. Neoadjuvant endocrine therapy in ER-positive breast cancer: evolution, indication, and tailored treatment strategy.
   Jeong H, Kim SB. · · 2023 · cited 4× · PMID 37786536 · DOI 10.1177/17588359231200457
8. Gene Expression Signatures for Guiding Initial Therapy in ER+/HER2- Early Breast Cancer.
   Marín-Liébana S, Llor P, Serrano-García L, Fernández-Murga ML, et al · · 2025 · cited 2× · PMID 40361409 · DOI 10.3390/cancers17091482