Novartis today announced results from an updated invasive disease-free survival (iDFS) analysis of the pivotal Phase III NATALEE trial, with a median follow-up of 33.3 months and following Kisqali® (ribociclib) treatment completion by 78.3% of patients. Results reinforce the benefit seen at the earlier interim analysis, with a 25.1% (HR=0.749; 95% CI: 0.628, 0.892; p=0.0006) reduction in risk of disease recurrence in patients with stage II and III hormone receptor-positive/human epidermal growth factor receptor 2-negative (HR+/HER2-) early breast cancer (EBC) treated with adjuvant Kisqali plus a non-steroidal aromatase inhibitor as standard endocrine therapy (ET) compared to ET alone1,2. Late-breaking data from this analysis will be presented today at the 2023 San Antonio Breast Cancer Symposium (SABCS) Annual Meeting.
Kisqali iDFS benefit across pre-specified subgroups1:
| Subgroup | 3-year iDFS rate, % | HR (95% Cl) |
| ITT population | Kisqali + ET: 90.7 | 0.749 |
| ET alone: 87.6 | (0.628, 0.892) | |
| AJCC Stage II | Kisqali + ET: 94.2 | 0.700 |
| ET alone: 92.6 | (0.496, 0.986) | |
| AJCC Stage III | Kisqali + ET: 88.1 | 0.755 |
| ET alone: 83.8 | (0.616, 0.926) | |
| Node-negative (N0) | Kisqali + AI: 93.2 | 0.723 |
| ET alone: 90.6 | (0.412, 1.268) |
“As clinicians, we know that patients diagnosed with HR+/HER2- early breast cancer remain at risk of recurrence for decades, despite adjuvant endocrine therapy. Moreover, the real risk observed in this analysis in patients treated with endocrine therapy alone, including those with node-negative disease, highlights the need for effective and tolerable treatment options that can help keep patients cancer-free in the short and long term,” said Gabriel N. Hortobagyi, MD, FACP, Professor of Breast Medical Oncology, The University of Texas MD Anderson Cancer Center. “The updated NATALEE results reinforce the potential of ribociclib to help address these needs for the broader at-risk population with no added disruptions to patients’ quality of life compared to endocrine therapy alone.”
Kisqali data across all secondary efficacy endpoints was also consistent, including distant disease-free survival (DDFS) (25.1% risk reduction) and recurrence-free survival (RFS) (27.3% risk reduction). With fewer than 4% of events in both treatment arms (3.3% in the Kisqali-ET arm and 3.4% in the ET only arm), overall survival (OS) results will continue to evolve in the longer term1,2.
The safety profile of Kisqali at the 400 mg dose remained consistent with previously reported results, with generally low-grade adverse events (AEs), other than laboratory abnormalities. AEs of special interest (grade 3 or higher) were neutropenia (44.3%), liver-related AEs (e.g., elevated transaminases) (8.6%), and QT interval prolongation (1.0%)1,2. No new safety signals were identified1,2.
“The final iDFS analysis of NATALEE represents a significant milestone, building upon the robust evidence supporting Kisqali as a potential new adjuvant treatment for a broad, clinically common and identifiable population of patients with stage II and III HR+/HER2- early breast cancer,” said Jeff Legos, Executive Vice President, Global Head of Oncology Development at Novartis. “We are seeking approval for Kisqali in early breast cancer from health authorities worldwide, aspiring to more than double the number of at-risk patients who could potentially benefit from CDK4/6 inhibitor treatment in this setting.”
Novartis submitted NATALEE data to the European Medicines Agency and plans to finalize submission to the U.S. Food and Drug Administration by end of year.
