US Food and Drug Administration Approval Summary: Ribociclib With an Aromatase Inhibitor in the Adjuvant Hormone Receptor–Positive, Human Epidermal Growth Factor Receptor 2–Negative Stage II and III High-Risk Early Breast Cancer Treatment Setting

J Jennifer J. Gao (US Food and Drug Administration, Silver Spring, MD) T Tatiana M. Prowell (Johns Hopkins Sidney Kimmel Comprehensive Cancer Center, Baltimore, MD) H Haley Gittleman (US Food and Drug Administration, Silver Spring, MD) J Joyce Cheng M Mallorie Fiero (US Food and Drug Administration, Silver Spring, MD) I Ilynn Bulatao (1FDA, Silver Spring, United States) G George Ching-Jey Chang (US Food and Drug Administration, Silver Spring, MD) T Tiffany K. Ricks (US Food and Drug Administration, Silver Spring, MD) F Francis Green (Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, MD) H Huali Wu J Jingyu Yu (US Food and Drug Administration, Silver Spring, MD) M Manuela Grimstein (US Food and Drug Administration, Silver Spring, MD) Y Yuching Yang (US Food and Drug Administration, Silver Spring, MD) H Hong Zhao Q Qi Liu R Rohit Kolhatkar (US Food and Drug Administration, Silver Spring, MD) T Tingting Gao C Chi-Ming Tu (US Food and Drug Administration, Silver Spring, MD) S Sherry Hou (US Food and Drug Administration, Silver Spring, MD) S Susan Redwood (US Food and Drug Administration, Silver Spring, MD) B Barbara Fuller (US Food and Drug Administration, Silver Spring, MD) L LaShawn Griffiths (US Food and Drug Administration, Silver Spring, MD) M Mispa Ajua-Alemanji (US Food and Drug Administration, Silver Spring, MD) C Courtney Leach (US Food and Drug Administration, Silver Spring, MD) S Stacie Woods (US Food and Drug Administration, Silver Spring, MD) O Oladimeji Akinboro (United States Food and Drug Administration - Center for Drug Evaluation and Research, Office of New Drugs, Office of Oncologic Diseases, Silver Spring, MD) P Preeti Narayan (US Food and Drug Administration, Silver Spring, MD) M Mirat Shah (Office of Oncologic Diseases, Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, MD) C Christy Osgood (US Food and Drug Administration, Silver Spring, MD) R Ramesh Raghavachari (US Food and Drug Administration, Silver Spring, MD) A Atiqur Rahman (US Food and Drug Administration, Silver Spring, MD) S Shenghui Tang (US Food and Drug Administration, Silver Spring, MD) V Vishal Bhatnagar N Nicole Gormley (US Food and Drug Administration, Silver Spring, MD) T Tamy Kim (US Food and Drug Administration, Silver Spring, MD) W William F. Pierce (US Food and Drug Administration, Silver Spring, MD) R Richard Pazdur (From the Oncology Center of Excellence (G.U.M., R.P.) and the Office of the Commissioner (N.N.B., R.M.C.), Food and Drug Administration, Silver Spring, MD.) P Paul G. Kluetz L Laleh Amiri-Kordestani

Abstract

PURPOSE On September 17, 2024, the US Food and Drug Administration (FDA) approved ribociclib in combination with an aromatase inhibitor (AI) for the adjuvant treatment of adults with hormone receptor–positive, human epidermal growth factor receptor 2 (HER2)–negative stage II and III early breast cancer (EBC) who are at high risk of recurrence. PATIENTS AND METHODS The FDA approval was based on NATALEE, a randomized (1:1), open-label, multicenter, multinational trial in adults of any sex or menopausal status with hormone receptor–positive, HER2-negative stage II and III EBC who received ribociclib plus an AI (Ribo + AI, n = 2,549) versus an AI (n = 2,552); patients also received goserelin as clinically indicated. Ribociclib was given at 400 mg once daily (3 weeks on/1 week off) for up to 36 months. AI was given per standard of care for at least 5 years. The primary end point was invasive disease-free survival (iDFS), defined according to Standardized Definitions for Efficacy End Points version 1.0 criteria. Overall survival (OS) was a secondary end point. RESULTS iDFS was statistically significant at the third interim analysis (IA3; January 2023; hazard ratio [HR], 0.75 [95% CI, 0.62 to 0.91]) in the intent-to treat (ITT) population. However, at IA3, there was a large amount of censoring for iDFS as only 20% of patients had completed 3 years of adjuvant therapy and OS was immature. Because of these concerns, FDA requested that NATALEE continue until the final iDFS analysis. At the final iDFS analysis, the iDFS at 36 months was 90.7% (95% CI, 89.3 to 91.8) for Ribo + AI versus 87.6% (95% CI, 86.1 to 88.9) for AI, with a HR of 0.75 (95% CI, 0.63 to 0.89). More patients who received ribociclib experienced all-grade (98% Ribo + AI v 88% AI) and grade ≥3 (64% Ribo + AI v 19% AI) adverse reactions (ARs). CONCLUSION Addition of adjuvant ribociclib to NSAI for adults with high-risk stage II and III hormone receptor–positive, HER2-negative EBC demonstrated a favorable benefit-risk profile with a statistically significant iDFS advantage. OS data remain immature.

Article Details

Volume / Issue Vol. 43, Issue 30
Published October 20, 2025
Pages 3312-3320
ISSN 0732-183X
Publisher Lippincott Williams & Wilkins

Journal Info

Journal of Clinical Oncology

Lippincott Williams & Wilkins

ISSN: 0732-183X Health Sciences

Authors (39)

J

Jennifer J. Gao

US Food and Drug Administration, Silver Spring, MD

T

Tatiana M. Prowell

Johns Hopkins Sidney Kimmel Comprehensive Cancer Center, Baltimore, MD

H

Haley Gittleman

US Food and Drug Administration, Silver Spring, MD

J

Joyce Cheng

M

Mallorie Fiero

US Food and Drug Administration, Silver Spring, MD

I

Ilynn Bulatao

1FDA, Silver Spring, United States

G

George Ching-Jey Chang

US Food and Drug Administration, Silver Spring, MD

T

Tiffany K. Ricks

US Food and Drug Administration, Silver Spring, MD

F

Francis Green

Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, MD

H

Huali Wu

J

Jingyu Yu

US Food and Drug Administration, Silver Spring, MD

M

Manuela Grimstein

US Food and Drug Administration, Silver Spring, MD

Y

Yuching Yang

US Food and Drug Administration, Silver Spring, MD

H

Hong Zhao

Q

Qi Liu

R

Rohit Kolhatkar

US Food and Drug Administration, Silver Spring, MD

T

Tingting Gao

C

Chi-Ming Tu

US Food and Drug Administration, Silver Spring, MD

S

Sherry Hou

US Food and Drug Administration, Silver Spring, MD

S

Susan Redwood

US Food and Drug Administration, Silver Spring, MD

B

Barbara Fuller

US Food and Drug Administration, Silver Spring, MD

L

LaShawn Griffiths

US Food and Drug Administration, Silver Spring, MD

M

Mispa Ajua-Alemanji

US Food and Drug Administration, Silver Spring, MD

C

Courtney Leach

US Food and Drug Administration, Silver Spring, MD

S

Stacie Woods

US Food and Drug Administration, Silver Spring, MD

O

Oladimeji Akinboro

United States Food and Drug Administration - Center for Drug Evaluation and Research, Office of New Drugs, Office of Oncologic Diseases, Silver Spring, MD

P

Preeti Narayan

US Food and Drug Administration, Silver Spring, MD

M

Mirat Shah

Office of Oncologic Diseases, Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, MD

C

Christy Osgood

US Food and Drug Administration, Silver Spring, MD

R

Ramesh Raghavachari

US Food and Drug Administration, Silver Spring, MD

A

Atiqur Rahman

US Food and Drug Administration, Silver Spring, MD

S

Shenghui Tang

US Food and Drug Administration, Silver Spring, MD

V

Vishal Bhatnagar

N

Nicole Gormley

US Food and Drug Administration, Silver Spring, MD

T

Tamy Kim

US Food and Drug Administration, Silver Spring, MD

W

William F. Pierce

US Food and Drug Administration, Silver Spring, MD

R

Richard Pazdur

From the Oncology Center of Excellence (G.U.M., R.P.) and the Office of the Commissioner (N.N.B., R.M.C.), Food and Drug Administration, Silver Spring, MD.

P

Paul G. Kluetz

L

Laleh Amiri-Kordestani