On October 17, 2025 Astrazeneca reported positive results from the MATTERHORN Phase III trial showed perioperative treatment with Imfinzi (durvalumab) in combination with standard-of-care FLOT (fluorouracil, leucovorin, oxaliplatin, and docetaxel) chemotherapy demonstrated a statistically significant and clinically meaningful improvement in the key secondary endpoint of overall survival (OS) versus chemotherapy alone. Patients were treated with neoadjuvant Imfinzi in combination with chemotherapy before surgery, followed by adjuvant Imfinzi in combination with chemotherapy, then Imfinzi monotherapy. The trial evaluated this regimen versus perioperative chemotherapy alone for patients with resectable, early-stage and locally advanced (Stages II, III, IVA) gastric and gastroesophageal junction (GEJ) cancers.

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These results will be presented today in a Proffered Paper session at the European Society for Medical Oncology (ESMO) (Free ESMO Whitepaper) Congress 2025 in Berlin, Germany (abstract #LBA81).

In the final OS analysis, results showed the Imfinzi and FLOT perioperative regimen reduced the risk of death by 22% compared with chemotherapy alone (based on a hazard ratio [HR] of 0.78; 95% confidence interval [CI] 0.63-0.96; p=0.021). Median OS was not yet reached for either arm. An estimated 69% of patients treated with the Imfinzi-based regimen were alive at three years compared with 62% in the FLOT-only arm.

Josep Tabernero, MD, PhD, head of the Medical Oncology Department at the Vall d’Hebron University Hospital and director of the Vall d’Hebron Institute of Oncology (VHIO) in Barcelona, Spain, and principal investigator in the trial, said: "The MATTERHORN data are transformative for patients with early gastric and gastroesophageal cancers, where recurrence is common and long-term prognosis remains poor despite curative-intent surgery and chemotherapy. Nearly seven in 10 patients treated with the durvalumab-based perioperative regimen were alive at three years, and the survival benefit was observed regardless of PD-L1 status. With results like these, this novel treatment should become the new standard of care in this curative-intent setting."

Susan Galbraith, Executive Vice President, Oncology Haematology R&D, AstraZeneca, said: "Imfinzi’s overall survival results, which demonstrate a 22 per cent reduction in the risk of death, could change the treatment paradigm for patients with early gastric and gastroesophageal cancers. This is the first immunotherapy-based perioperative regimen to significantly extend survival in this setting, and these results illustrate our strategy to move novel treatments into early-stage cancers where cure is possible."

Summary of OS results: MATTERHORN

Imfinzi-based regimen

(n=474)

Chemotherapy regimen

(n=474)

OS i,ii

mOS (in months)iii

NR (NR-NR)

NR (NR-NR)

HR (95% CI) iv

0.78 (0.63-0.96)

Stratified log-rank p-value

0.021

Number of deaths, n (%)

160 (33.8)

192 (40.5)

Data maturity

37.1%

OS rate at 18 months, %iii

81.1

77.1

OS rate at 24 months, %iii

75.5

70.4

OS rate at 36 months, %iii

68.6

61.9

OS, PD-L1 TAP ≥1% (n)v

426

427

Number of deaths, n (%)

143 (33.6%)

172 (40.3%)

mOS (in months)

NR (NR-NR)

NR (NR-NR)

HR (95% CI)

0.79 (0.63-0.99)

OS, PD-L1 TAP <1% (n)v

48

47

Number of deaths, n (%)

17 (35.4%)

20 (42.6%)

mOS (in months)

NR (43.66-NR)

NR (21.72-NR)

HR (95% CI)

0.79 (0.41-1.50)

i. OS data cut-off date was 1 September 2025
ii. Median follow-up duration for OS in all subjects at data cut-off: 39.6 months for Imfinzi plus FLOT and 38.6 months for placebo plus FLOT
iii. Calculated by Kaplan–Meier method
iv. The analysis was performed using a stratified Cox proportional hazards model, adjusting for geographic region, clinical lymph node status and PD-L1 expression status
v. TAP, Tumour area positivity

Significance threshold p <0.0499
NR, not yet reached

Results from an additional analysis of the association between pathologic outcomes and event-free survival (EFS) in MATTERHORN demonstrated that any degree of pathologic response was associated with improved EFS in the Imfinzi arm versus the comparator arm (pathologic complete response [pCR] HR 0.29; 95% CI, 0.08-0.96; major pathologic response [MPR] HR 0.32; 95% CI, 0.15-0.68); any pathologic response: HR 0.60; 95% CI, 0.46-0.79). Additionally, EFS was improved regardless of pathologic lymph node status at the time of surgery (no nodal involvement: HR 0.74; 95% CI, 0.46-1.18; nodal involvement: HR 0.77; 95% CI, 0.58-1.02).

In a previously reported interim analysis for the key primary endpoint of EFS, patients treated with the Imfinzi-based perioperative regimen showed a 29% reduction in the risk of disease progression, recurrence or death versus chemotherapy alone (based on an EFS hazard ratio [HR] of 0.71; 95% confidence interval [CI] 0.58-0.86; p<0.001). The safety profile for Imfinzi and FLOT chemotherapy was consistent with the known profiles of each medicine, and the percentage of patients that completed surgery was similar compared to chemotherapy alone. Grade 3 or higher adverse events due to any cause were similar between the two arms.

Notes
Gastric and gastroesophageal junction cancers

Gastric (stomach) cancer is the fifth most common cancer worldwide and the fifth-highest leading cause of cancer mortality.1 Nearly one million new patients were diagnosed with gastric cancer in 2022, with approximately 660,000 deaths reported globally.1 In many regions, its incidence has been increasing in patients younger than 50 years old, along with other gastrointestinal (GI) malignancies.2 In 2024, there were approximately 43,000 drug-treated patients in the US, European Union (EU), and Japan with early-stage and locally advanced gastric or GEJ cancer.3 Approximately 62,000 patients in these regions are expected to be newly diagnosed in this setting by 2030.4

GEJ cancer is a type of gastric cancer that arises from and spans the area where the oesophagus connects to the stomach.5

Disease recurrence is common in patients with resectable gastric cancer despite undergoing surgery with curative intent and treatment with neoadjuvant/adjuvant chemotherapy.6 Approximately one in four patients with gastric cancer who undergo surgery develop recurrent disease within one year, and the five-year survival rate remains poor, with less than half of patients alive at five years.6-7

MATTERHORN
MATTERHORN is a randomised, double-blind, placebo-controlled, multi-centre, global Phase III trial evaluating Imfinzi as perioperative treatment for patients with resectable Stage II-IVA gastric and GEJ cancers. Perioperative therapy includes treatment before and after surgery, also known as neoadjuvant/adjuvant therapy. In the trial, 948 patients were randomised to receive a 1500mg fixed dose of Imfinzi plus FLOT chemotherapy or placebo plus FLOT chemotherapy every four weeks for two cycles prior to surgery. This was followed by Imfinzi or placebo every four weeks for up to 12 cycles after surgery (including two cycles of Imfinzi or placebo plus FLOT chemotherapy and 10 additional cycles of Imfinzi or placebo monotherapy).

In the MATTERHORN trial, the primary endpoint is EFS, defined as time from randomisation until the date of one of the following events (whichever occurred first): RECIST (version 1.1, per blinded independent central review assessment) progression that precludes surgery or requires non-protocol therapy during the neoadjuvant period; RECIST progression/recurrence during the adjuvant period; non-RECIST progression that precludes surgery or requires non-protocol therapy during the neoadjuvant period or discovered during surgery; progression/recurrence confirmed by biopsy post-surgery; or death due to any cause. Key secondary endpoints include pathologic complete response rate, defined as the proportion of patients who have no detectable cancer cells in resected tumour tissue following neoadjuvant therapy, and OS. The trial enrolled participants in 176 centres in 20 countries, including in the US, Canada, Europe, South America and Asia.

Imfinzi
Imfinzi (durvalumab) is a human monoclonal antibody that binds to the PD-L1 protein and blocks the interaction of PD-L1 with the PD-1 and CD80 proteins, countering the tumour’s immune-evading tactics and releasing the inhibition of immune responses.

In GI cancer, Imfinzi is approved in combination with chemotherapy in locally advanced or metastatic biliary tract cancer (BTC) and in combination with Imjudo (tremelimumab) in unresectable hepatocellular carcinoma (HCC). Imfinzi is also approved as a monotherapy in unresectable HCC in Japan and the EU.

In addition to its indications in GI cancers, Imfinzi is the global standard of care based on OS in the curative-intent setting of unresectable, Stage III non-small cell lung cancer (NSCLC) in patients whose disease has not progressed after chemoradiotherapy (CRT). Additionally, Imfinzi is approved as a perioperative treatment in combination with neoadjuvant chemotherapy in resectable NSCLC, and in combination with a short course of Imjudo and chemotherapy for the treatment of metastatic NSCLC. Imfinzi is also approved for limited-stage small cell lung cancer (SCLC) in patients whose disease has not progressed following concurrent platinum-based CRT; and in combination with chemotherapy for the treatment of extensive-stage SCLC.

Perioperative Imfinzi in combination with neoadjuvant chemotherapy is approved in the US, EU, Japan and other countries for patients with muscle-invasive bladder cancer based on results from the NIAGARA Phase III trial. Additionally, in May 2025, Imfinzi added to Bacillus Calmette-Guérin induction and maintenance therapy met the primary endpoint of disease-free survival for patients with high-risk non-muscle-invasive bladder cancer in the POTOMAC Phase III trial.

Imfinzi in combination with chemotherapy followed by Imfinzi monotherapy is approved as a 1st-line treatment for primary advanced or recurrent endometrial cancer (mismatch repair deficient disease only in the US and EU). Imfinzi in combination with chemotherapy followed by Lynparza (olaparib) and Imfinzi is approved for patients with mismatch repair proficient advanced or recurrent endometrial cancer in the EU and Japan.

Since the first approval in May 2017, more than 414,000 patients have been treated with Imfinzi. As part of a broad development programme, Imfinzi is being tested as a single treatment and in combinations with other anti-cancer treatments for patients with NSCLC, bladder cancer, breast cancer, ovarian cancer and several GI cancers.

(Press release, AstraZeneca, OCT 17, 2025, View Source [SID1234656741])

On October 17, 2025 TOLREMO therapeutics AG (TOLREMO) reported encouraging clinical data from 34 patients with advanced solid tumors treated with TT125-802 in the dose escalation part of an ongoing first-in-human study (NCT06403436). The data will be presented on October 19 at the European Society of Medical Oncology (ESMO) (Free ESMO Whitepaper) Congress 2025 in Berlin, Germany, and highlights TT125-802’s confirmed clinical activity and favorable safety profile.

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TT125-802 is an orally available small-molecule inhibitor that selectively blocks the bromodomains of CBP/p300, transcriptional co-activators implicated in non-oncogene addiction – a key driver of cancer and drug resistance that functions in parallel to oncogenic pathways. This update expands on initial data presented at ASCO (Free ASCO Whitepaper) earlier this year, establishing TT125-802 as the first CBP/p300 bromodomain inhibitor to report clinical activity across a variety of solid tumors, including durable confirmed responses in non-small cell lung cancer (NSCLC).

In the now completed dose escalation part of the study, 34 heavily pre-treated solid tumor patients received TT125-802 across 5 dose escalation cohorts (15 mg QD – 60 mg BID) and 2 cohorts examining the role of food on exposures. No MTD was reached and TT125-802 was safe and well tolerated. The most common drug-related AEs were dysgeusia and hyperglycemia. No thrombocytopenia was observed. The recommended dose was selected at 60 mg once a day on a continuous basis, without food restriction.

Suppression of CBP/p300 target pathways was confirmed in patient hair follicles by RNA-seq.

Anti-tumor activity was observed across all dose levels in this heavily pre-treated population. 4 patients stayed on study for over one year, including 3 patients with adenoid cystic carcinoma and one patient with a bulky dedifferentiated liposarcoma. 3 patients (EGFR exon 19 delta, KRAS-G12C, squamous NSCLC) achieved a deep confirmed partial response (PR). The EGFRmut and KRAS-G12Cmut patients had progressed on an EGFR inhibitor and KRAS-G12C inhibitor, respectively, in a prior line of therapy. Both had a rapid PR after 6 weeks of TT125-802 monotherapy and remained progression-free for almost 7 months. The squamous NSCLC patient had progressed on standard-of-care therapy and had a PR after 12 weeks of TT125-802. The patient was on study for 5.5 months until progression.

Dr. Omar Saavedra Santa Gadea at NEXT Oncology Hospital Quirónsalud in Barcelona, an investigator on the study said, "It is remarkable to see such rapid, deep and durable responses in NSCLC patients who had exhausted all prior treatments. TT125-802’s mechanism targeting non-oncogene addiction offers a novel approach to improving clinical outcomes for patients in this high-need setting."

"These results validate our approach to target epigenetic mechanisms driving cancer and drug resistance and support the continued clinical development of TT125-802 in patients with solid tumors and hematological malignancies," said Florian Vogl, CMO at TOLREMO. "The absence of thrombocytopenia, a common toxicity with bromodomain inhibitors, sets TT125-802 apart. The wide therapeutic window opens up clinical opportunities for TT125-802 which have so far been unattainable for this class of drugs."

"We will now initiate a combination study investigating the efficacy of TT125-802 in combination with an EGFR inhibitor and a KRAS-G12C inhibitor in the respective oncogene-driven NSCLC populations, and with docetaxel in squamous NSCLC patients. We look forward to demonstrating the full therapeutic potential of TT125-802 for patients in need," said Stefanie Flückiger-Mangual, Ph.D., CEO and co-founder of TOLREMO.

Details of the poster presentations are:

Abstract Title: Clinical activity of TT125-802, a highly selective bromodomain inhibitor of CBP/p300, in advanced solid tumors: update on the ongoing phase I study

Authors: O. Saavedra, E. Garralda, V. Boni, J. Fuentes Antrás, I. Colombo, M. Imbimbo, G. Molina, I. Braña, K. Homicsko, F.D. Vogl, D. Gruber, S. Costanzo, A. Cesano, S. Flückiger-Mangual

Category: Developmental Therapeutics

Presentation Number: 978P

Date/Time: 19 October 2025 / 12:00 – 12:45 CEST

TOLREMO is assessing TT125-802 in a first-in-human, multicenter Phase 1 trial (NCT06403436) to evaluate the safety, tolerability, pharmacokinetics, and efficacy in patients with advanced solid tumors. The company recently received two U.S. FDA Fast Track designations for the treatment of patients with advanced or metastatic EGFR-mutant or KRAS-G12C-mutant NSCLC with disease progression on at least one prior line of therapy.

(Press release, TOLREMO, OCT 17, 2025, View Source [SID1234656739])

On October 17, 2025 Sona Nanotech Inc. (CSE: SONA) (OTCQB: SNANF) (the "Company", "Sona"), reported that it will host a webinar on Monday, October 20th at noon EDT to discuss its first-in-human, early feasibility clinical study for its Targeted Hyperthermia Therapy cancer treatment. Ten advanced stage melanoma patients who were failing to respond to standard immunotherapy treatment were recruited into this early feasibility study.

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Interested parties can register here: http://bit.ly/3JcFls5. A recording of the webinar will be made available following the webinar in the Investor Information section of the Company’s website.

(Press release, Sona Nanotech, OCT 17, 2025, View Source [SID1234656738])

On October 17, 2025 Sensei Biotherapeutics, Inc. (Nasdaq: SNSE), a clinical-stage biotechnology company focused on the discovery and development of next-generation therapeutics for cancer patients, reported results from the dose expansion portion of its Phase 1/2 trial evaluating solnerstotug (formerly SNS-101), a conditionally active monoclonal antibody targeting VISTA (V-domain Ig suppressor of T cell activation). The data will be shared today during a mini oral session at the ESMO (Free ESMO Whitepaper) Congress 2025.

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The Phase 1 dose expansion is a multi-center, open-label study evaluating solnerstotug as monotherapy and in combination with Libtayo (cemiplimab), Regeneron’s PD-1 inhibitor. The study enrolled patients with a basket of "hot" tumor types (that typically respond to immunotherapy) (n=44), of whom 41 had previously received and progressed on PD-(L)1 therapy, as well as patients with "cold" tumor types (that typically exhibit primary resistance to immunotherapy) (n=20).

Patients who progress following treatment with PD-(L)1 inhibitors ("secondary resistance") face a particularly poor prognosis, as resistance to immune checkpoint blockade is a significant challenge in oncology. For patients who develop secondary resistance, the likelihood of benefiting from a rechallenge with the same therapy is estimated to be 5% or less.1

Currently, treatment options for PD-(L)1 resistant tumors are limited, with many patients receiving chemotherapy, experimental therapies in clinical trials, or palliative care in the absence of effective alternatives. While historical benchmarks in this setting are limited, docetaxel, which is widely used in the 2nd line post-PD-(L)1 setting for Non-Small Cell Lung Cancer (NSCLC), typically has a 6-month PFS of 10-20% in similar patient populations.2 To date, immune checkpoint inhibitor (ICI) combination therapies have not been approved in this setting.

Emerging Clinical Signal and Favorable Tolerability Profile

As of the September 8, 2025, data cutoff, 35 efficacy-evaluable "hot tumor" patients had received cemiplimab with either 15 mg/kg (n=19) or 3 mg/kg dose (n=16) of solnerstotug. Six clinical responses, including five in patients with PD-(L)1 resistant tumors, occurred at the higher 15 mg/kg solnerstotug dose, and no objective responses were observed at the 3 mg/kg dose.

Among 41 "hot tumor" patients that received and progressed on a prior PD-(L)1 therapy, the overall 6-month PFS rate was 37%, which compares favorably with historical benchmarks in this setting. At 15 mg/kg, 6-month PFS reached 50% among PD-(L)1 resistant patients, surpassing rates historically seen in this treatment-refractory population. At 3 mg/kg, 6-month PFS was 24% among PD-(L)1 resistant patients.

Solnerstotug was well tolerated at both 3 mg/kg and 15 mg/kg doses in combination with cemiplimab:

Only six mild (Grade 1) CRS events were observed across all patients in Phase 1 (n=98), all manageable.
No new safety signals were identified across dose expansion (n=64).
The safety profile remains consistent with prior data and compares favorably to other checkpoint inhibitor combinations in this population.

"We believe solnerstotug’s emerging dose-dependent activity in refractory ‘hot’ tumors, combined with a favorable tolerability profile, support its advancement into Phase 2 studies," said Ron Weitzman, M.D., Chief Medical Officer of Sensei Biotherapeutics. "The data suggest that selective blockade of VISTA within the tumor microenvironment may help re-engage exhausted T cells, even after PD-1 failure, a goal long considered out of reach."

In addition to the "hot" tumor cohorts, 20 patients with Microsatellite Stable Colorectal (MSS CRC) "cold" tumors were treated with either solnerstotug as monotherapy or in combination with cemiplimab (350 mg). No responses were observed and the safety profile was consistent with previously reported data.

Durable Disease Control in "Hot" Tumors Followed by Late Onset Responses

Four out of six responders demonstrated prolonged disease control, followed by a late onset response (occurring between 18 and 54 weeks). PD-(L)1 therapies typically have a time to response of 2–3 months, indicating that the combination of solnerstotug plus cemiplimab has a unique and differentiated pattern of activity.

At the 15 mg/kg dose of solnerstotug, notable responses included:

A Merkel Cell Carcinoma (MCC) patient with a durable complete response at week 18 and a duration of response of 54+ weeks
A Microsatellite Instability-High Colorectal Cancer (MSI-H CRC) patient with a partial response (PR) at week 36 and a 33+ week duration
An NSCLC patient with a tumor proportion score less than 5% that was PD-1 naïve had a PR at week 54 and duration of response of 15+ weeks
An Esophageal Cancer patient with a PR at Week 24 and a duration of response of 6 weeks

"This pattern of delayed, durable responses is unusual among immunotherapies," said Kyriakos Papadopoulos, M.D., Co-Director of Clinical Research at START, San Antonio. "It may indicate that solnerstotug acts through a mechanism that is complementary to PD-(L)1 in resistant tumors."

Next Steps: Planned Phase 2 Studies to Evaluate Efficacy in a Commercially Attractive Indication and Potentially Pursue Accelerated Approval in a PD-1 Resistant Population

Sensei is planning two Phase 2 studies to begin in 2026, subject to FDA feedback and the Company’s ability to raise sufficient capital. The first is expected to be a randomized trial in 2nd line NSCLC where patients have received and failed anti-PD-(L)1 treatment. Patients would be randomized to receive either the combination of solnerstotug + a PD-(L)1 inhibitor or chemotherapy.

The second trial is expected to be a single arm study in PD-(L)1 resistant MCC patients where there is limited therapeutic optionality and potential for accelerated approval, subject to FDA feedback.

"We’re pleased by the emerging signs of dose-related activity, durability, and a favorable safety profile—key characteristics of a potentially differentiated immunotherapy," said John Celebi, President and Chief Executive Officer of Sensei Biotherapeutics. "These results provide a foundation for our planned Phase 2 development program as we work to better define solnerstotug’s role in treating challenging patient populations."

(Press release, Sensei Biotherapeutics, OCT 17, 2025, View Source/news-releases/news-release-details/sensei-biotherapeutics-reports-new-clinical-results-highlighting" target="_blank" title="View Source/news-releases/news-release-details/sensei-biotherapeutics-reports-new-clinical-results-highlighting" rel="nofollow">View Source [SID1234656737])

Investor Webcast Information

Sensei will host an investor webcast on October 20th at 8:00 AM ET, featuring company leadership and Kyriakos Papadopoulos, MD, Co-Director of Clinical Research at START, San Antonio.

Register for the event here. A replay will be available after the webcast on the Investor Relations page of Sensei’s website: View Source

On October 17, 2025 Novartis reported results from the five-year analysis of the pivotal Phase III NATALEE trial of Kisqali (ribociclib) that demonstrated a sustained benefit at a median of two years after a three-year treatment with Kisqali (median follow-up: 58.4 months). Results showed a 28.4% reduction in risk of recurrence (HR=0.716; 95% CI 0.618-0.829; nominal p-value <0.0001) in the broadest population of patients with high-risk stage II and III hormone receptor-positive/human epidermal growth factor receptor 2-negative (HR+/HER2-) early breast cancer (EBC) treated with Kisqali plus endocrine therapy (ET) compared to ET alone1.

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The five-year invasive disease-free survival (iDFS) rates were 85.5% in the Kisqali plus ET arm versus 81.0% in the ET alone arm, representing a clinically meaningful 4.5% improvement1. These late-breaking results will be presented at the European Society for Medical Oncology (ESMO) (Free ESMO Whitepaper) Congress 2025.

"For the thousands of people diagnosed with early breast cancer each year, the fear of recurrence, often as incurable advanced disease, weighs heavily on patients and their families," said Dr. John Crown, Consultant Medical Oncologist at St. Vincent’s University Hospital, Dublin, and NATALEE investigator. "These five-year results show that the benefit of ribociclib persists well beyond the completion of treatment, offering these at-risk patients a greater chance of living breast cancer-free."

As follow-up continued, the confidence intervals (CIs) became narrower1. This pattern held across clinically relevant subgroups, reinforcing the robustness of the observed iDFS benefit1.

"These data reinforce the potential of Kisqali to significantly reduce the long-term risk of breast cancer recurrence, extending well beyond the three-year treatment period. This provides physicians and patients with greater confidence in long-term disease management. Kisqali is redefining the standard of care in adjuvant therapy, including in patients with node-negative disease," said Dushen Chetty, Global Head of Oncology and Hematology Development at Novartis, Ad Interim. "The consistency of the benefit observed across both advanced and early breast cancer settings, together with Kisqali’s established safety profile, underscores its position as the CDK4/6 inhibitor with the most comprehensive Phase III evidence base for improving patient outcomes."

Overall survival (OS) continues to show an encouraging trend, with further improvement in the hazard ratio (HR) to 0.800 and narrowing CI (95% CI: 0.637-1.003; one-sided nominal p-value 0.026) compared to the final iDFS analysis (OS HR = 0.892 (0.661-1.203)), demonstrating a 20% reduction in the risk of death compared to ET alone1. The NATALEE trial will continue follow-up to ensure sufficient data is collected for OS and other long-term endpoints.

iDFS results across pre-specified subgroups1:

Subgroups Hazard ratio 95% CI Absolute risk reduction at 5 years
Overall population 0.716 0.618-0.829 4.5%
Stage II 0.660 0.493-0.884 3.7%
Stage III 0.730 0.615-0.865 5.6%
Node-negative (N0) 0.606 0.372-0.986 5.7%
Node-positive (N1-3) 0.737 0.631-0.860 4.4%
With a median of around two years after all patients completed Kisqali treatment, long-term safety shows no new safety signals1. Overall, rates of secondary primary malignancies (SPMs) were 2.7% (Kisqali plus ET) and 3.0% (ET alone), while SPMs leading to deaths were reported in one patient in each group1.

Kisqali remains the only CDK4/6 inhibitor to demonstrate statistically significant OS benefits across three randomized controlled trials in advanced breast cancer (MONALEESA-2, MONALEESA-3, and MONALEESA-7)2-12.

*OS data remain immature at the five-year NATALEE analysis

About NATALEE
NATALEE is a global Phase III multi-center, randomized, open-label trial to evaluate the efficacy and safety of Kisqali with ET as an adjuvant treatment versus ET alone in the broadest range of patients with stage II and III HR+/HER2- EBC, being conducted in collaboration with TRIO13,14. The adjuvant ET in both treatment arms was a non-steroidal aromatase inhibitor (NSAI; anastrozole or letrozole) and goserelin if applicable13,14. The primary endpoint of NATALEE is invasive disease-free survival (iDFS) as defined by the Standardized Definitions for Efficacy End Points (STEEP) criteria13,14. A total of 5,101 adult patients with HR+/HER2- EBC across 20 countries were randomized in the trial13,14.

About Kisqali (ribociclib)
Kisqali (ribociclib) is a selective cyclin-dependent kinase inhibitor, helping slow the progression of cancer by inhibiting two proteins called cyclin-dependent kinase 4 and 6 (CDK4/6). These proteins, when over-activated, enable cancer cells to grow and divide quickly. Targeting CDK4/6 with enhanced precision plays a role in tumor control.

Kisqali has been approved as a treatment for breast cancer by regulatory authorities in more than 100 countries worldwide, including the U.S. FDA and the European Commission15,16. In the US, Kisqali is indicated in combination with an AI as an adjuvant treatment for adults with HR+/HER2- stage II and III early breast cancer at high risk of recurrence, as well as for the treatment of adults with HR+/HER2- advanced or MBC as initial ET; Kisqali is also approved in the metastatic indication in combination with fulvestrant as initial ET or following disease progression on ET15. In the EU, Kisqali is approved in combination with an AI for the adjuvant treatment of patients with HR+/HER2- early breast cancer at high risk of recurrence; and for the treatment of women with HR+/HER2- advanced or MBC in combination with either an AI or fulvestrant as initial ET or following disease progression16. In pre- or peri-menopausal women, the ET should be combined with a luteinizing hormone-releasing hormone agonist15,16.

In EBC, Kisqali is the only CDK4/6 inhibitor recommended by the NCCN Guidelines for breast cancer as Category 1 preferred for both all node-positive disease as well as for patients with no nodal involvement with high-risk disease characteristics, such as tumor size >5 cm, or for tumors sized 2-5 cm, either Grade 2 with high genomic risk/Ki-67 ≥20% or Grade 317. Kisqali approvals in EBC from regulatory authorities worldwide are ongoing, including recent approval from China’s National Medical Products Administration18. In MBC, Kisqali has consistently demonstrated statistically significant overall survival benefit across three Phase III trials2-12. The NCCN Guidelines also recommend Kisqali as the only Category 1 preferred CDK4/6 inhibitor for first-line treatment of people living with HR+/HER2- MBC when combined with an AI, making Kisqali the preferred first-line treatment of choice for US prescribers in HR+/HER2- MBC17.

In addition, Kisqali has achieved the highest score (A) on the European Society for Medical Oncology-Magnitude of Clinical Benefit Scale (ESMO-MCBS) for EBC19; and has the highest rating of any CDK4/6 inhibitor on the ESMO (Free ESMO Whitepaper) Magnitude of Clinical Benefit Scale, achieving a score of four out of five for first-line pre-menopausal patients with HR+/HER2- advanced breast cancer20. Further, Kisqali in combination with either letrozole or fulvestrant has uniquely, among other CDK4/6 inhibitors, received a score of four out of five for post-menopausal patients with HR+/HER2- advanced breast cancer treated in the first line21.

Kisqali was developed by Novartis under a research collaboration with Astex Pharmaceuticals.

(Press release, Novartis, OCT 17, 2025, View Source [SID1234656736])