"Kisqali's adjuvant therapy, results from the NATALEE study"

Unveiled at the ESMO Congress 2025…the survival gap in patients who relapsed at 5th-7th year has widened

The long-term survival curve in early breast cancer has widened, drawing attention to its clinical significance

Inhibits early recurrence with 3-year dosing design…evidence for 400mg dosage has been secured

The 5-year follow-up results of the NATALEE study, unveiled at the European Society for Medical Oncology (ESMO Congress 2025), are drawing significant attention.

 

The data suggest the potential for further widening of the long-term survival curves across a broad patient population, including lower-risk groups such as node-negative patients.

 

This evidence is evaluated as expanding the potential for 'complete remission access' in early breast cancer treatment.

 

Im Seock-Ah of Seoul National University Hospital's Division of Hematology-Medical Oncology assessed that "Patients who are node-negative (N0) or have 1-3 positive nodes often relapse at 5th-7th year," and said, "The preventive effect in this late-relapse patient group will further widen the long-term survival gap." "3-year dosing design, clear evidence for inhibiting early recurrence"

Im Seock-Ah of Seoul National University Hospital

Hormone Receptor-positive (HR+) / HER2-negative (HER2-) breast cancer is known to account for approximately 70% of all breast cancers.

 

Furthermore, it is reported that one-third of stage 2 patients and over half of stage 3 patients experience recurrence even after the standard Endocrine Therapy (ET).

 

The NATALEE study is a Phase 3 clinical trial evaluating the long-term recurrence prevention effect of Kisqali (ribociclib, 400mg, 3 weeks on/1 week off) combination therapy compared to non-steroidal aromatase inhibitor (NSAI) monotherapy in 5,101 patients with high-risk stage 2-3 HR+/HER2- early breast cancer.

 

Regarding Kisqali's adjuvant therapy design, Professor Im explained, "The peak of recurrence is most pronounced between 2 and 3 years post-surgery.

 

Continuing treatment for three years to cover this period has clear clinical evidence." She stated, "We have pharmacodynamic data showing that target inhibition is possible even at the 400mg dose, and the suppression of early recurrence is the key factor that widens the gap between the future iDFS and OS curves." The current Hazard Ratio (HR) in the NATALEE study is around 0.8, already indicating a positive outcome.

 

Professor Im assessed that the study is following the same trend as the monarchE study of Verzenio (abemaciclib), which demonstrated improvement in Overall Survival (OS) in its 7-year follow-up analysis.

 

Professor Im emphasized, "As the follow-up of the NATALEE study continues, OS improvement will clearly become visible within 3-4 years." She stressed, "Even an absolute benefit of 2-3% in adjuvant therapy is clinically significant, and the large-scale design of breast cancer studies is intended to secure this statistical power." "Reducing non-reimbursement burden...

 

high economic acceptance" Professor Im also mentioned that patient access to Kisqali in clinical practice is relatively high, although it is currently non-reimbursed.

 

She said, "Novartis is trying to improve price accessibility, and some patients can receive assistance from private insurance," and added, "The perception of it being a 'high-cost new drug' has decreased since it has been used for over seven years in metastatic breast cancer." Professor Im believes that patients view the cost not as spending millions of KRW to live a few more months with metastatic cancer, but as investing a significantly smaller amount to 'live a healthy life forever.' This perspective results in a relatively high rate of patients choosing the drug in clinical practice.

 

However, the patient burden due to the non-reimbursed status still exists.

 

Professor Im also shared her view that simply differentiating between overlapping patient populations when future reimbursement is applied would not be desirable.

 

She emphasized, "Since there are patients who need to switch to Kisqali due to side effects from abemaciclib, or vice versa, the system should allow for flexible patient choice based on individual circumstances." She stressed, "Restrictions like 'you can't use this because an alternative drug exists' ultimately limit patient freedom.

 

The system should be more open based on scientific evidence." Finally, Professor Im concluded by stressing the importance of 'precision medicine' as the future direction for breast cancer treatment, alongside discussions on treatment access.

 

She stated, "Although breast cancer treatment is nearing a cure, there is a need to precisely differentiate the biological differences between the patient group that rapidly progresses early on and the long-term survival group." Professor Im also pointed out, "Genomic testing and biomarker analysis are the answers, but since they are not covered by insurance, the patient burden reaches 80%." He added, "Genuine long-term survival is only possible when medical professionals' scientific judgment is trusted and the system adopts a more flexible approach."