Summit Therapeutics Announces Expansion of Ivonescimab Global Phase III Development Program with HARMONi-GI3 Study in 1L Colorectal Cancer

On October 17, 2025 Summit Therapeutics Inc. (NASDAQ: SMMT) ("Summit," "we," or the "Company") reported the expansion of its Phase III clinical development program of the novel, potential first-in-class investigational bispecific antibody, ivonescimab, into colorectal cancer (CRC) with the initiation of the global Phase III HARMONi-GI3 trial.

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Summit is starting a Phase III clinical study, HARMONi-GI3, to evaluate ivonescimab plus chemotherapy compared to bevacizumab plus chemotherapy as first line therapy in patients with unresectable metastatic colorectal cancer (CRC).

Clinical trial sites for HARMONi-GI3 are planned to begin activating in the United States prior to the end of the year. The multiregional study intends to enroll approximately 600 patients. The primary endpoint for this study is progression-free survival.

Each year, approximately 48,000 patients are estimated to be diagnosed with or have unresectable recurrent metastatic MSS CRC (also known as mismatch repair-proficient colorectal cancer, or pMMR CRC).1 There have been limited options approved in the United States in the last 20 years for those first-line patients whose tumors are not positive for certain biomarkers or other activating mutations.

MSS CRC is a setting where monoclonal PD-1 inhibitors such as pembrolizumab and nivolumab have failed to show a clinically meaningful benefit. Anti-VEGF therapy (e.g., bevacizumab) plus chemotherapy is the standard of care for many patients with 1L metastatic MSS CRC.

At the 2024 Annual Congress of the European Society of Medical Oncology (ESMO) (Free ESMO Whitepaper) (ESMO 2024), Akeso Inc. (Akeso) presented encouraging Phase II data of ivonescimab in combination with FOLFOXIRI chemotherapy demonstrating an objective response rate (ORR) of 81.8% (95% CI: 59.7% – 94.8%) and a disease control rate (DCR) of 100% (95% CI: 84.6% – 100.0%) in 22 patients. This Phase II study, AK112-206, was conducted in China and sponsored by Akeso with all relevant data exclusively generated, managed, and analyzed by Akeso. In the ivonescimab plus FOLFOXIRI chemotherapy arm, there were no treatment emergent adverse events that led to permanent discontinuation of ivonescimab as of the data cutoff from the ESMO (Free ESMO Whitepaper) 2024 presentation.

Subsequently, AK112-206 was expanded to include additional patients from the United States and China to study ivonescimab in combination with FOLFOX chemotherapy. FOLFOX in combination with a monoclonal antibody such as bevacizumab represents a preferred treatment regimen for physicians treating patients in the United States and other western territories. The data from the initial patient cohort presented at ESMO (Free ESMO Whitepaper) 2024 have continued to mature, in addition to the global Phase II data generated in combination with FOLFOX in the United States and China, which support the Phase III HARMONi-GI3 study design using FOLFOX.

"As promised earlier in the year, we sought to expand the ivonescimab clinical development program beyond non-small cell lung cancer in order to continue to explore the potential benefits of its specifically-engineered, novel design and mechanism of action, including its cooperative binding attributes," stated Robert W. Duggan and Dr. Maky Zanganeh, Co-Chief Executive Officers of Summit. "Microsatellite stable colorectal cancer represents a global unmet need whereby ivonescimab has the potential to bring the benefits of immunotherapy to solid tumors where PD-1 monoclonal antibodies have not been able to successfully improve upon existing standards of care. We are thrilled by the potential of ivonescimab to make a significant difference to these patients with few front-line options available today."

Conference Call

Summit Therapeutics Inc. will host a conference call and live webcast to discuss recent updates related to ivonescimab, including data released at ESMO (Free ESMO Whitepaper), on Monday, October 20, 2025, at 8:00am ET. Conference call and webcast information will be accessible through our website www.smmttx.com.

An archived edition of the webcast will be available on our website later in the day on Monday.

About Ivonescimab

Ivonescimab, known as SMT112 in Summit’s license territories, North America, South America, Europe, the Middle East, Africa, and Japan, and as AK112 in China and Australia, is a novel, potential first-in-class investigational bispecific antibody combining the effects of immunotherapy via a blockade of PD-1 with the anti-angiogenesis effects associated with blocking VEGF into a single molecule. Ivonescimab displays unique cooperative binding to each of its intended targets with multi-fold higher affinity to PD-1 when in the presence of VEGF.

This could differentiate ivonescimab as there is potentially higher expression (presence) of both PD-1 and VEGF in tumor tissue and the tumor microenvironment (TME) as compared to normal tissue in the body. Ivonescimab’s specifically engineered tetravalent structure (four binding sites) enables higher avidity (accumulated strength of multiple binding interactions) in the TME (Zhong, et al., SITC (Free SITC Whitepaper), 2023). This tetravalent structure, the intentional novel design of the molecule, and bringing these two targets into a single bispecific antibody with cooperative binding qualities have the potential to direct ivonescimab to the tumor tissue versus healthy tissue. The intent of this design, together with a half-life of 6 to 7 days after the first dose (Zhong, et al., SITC (Free SITC Whitepaper), 2023) increasing to approximately 10 days at steady state dosing, is to improve upon previously established efficacy thresholds, in addition to side effects and safety profiles associated with these targets.

Ivonescimab was engineered by Akeso Inc. (HKEX Code: 9926.HK) and is currently engaged in multiple Phase III clinical trials. Over 3,000 patients have been treated with ivonescimab in clinical studies globally.

Summit began its clinical development of ivonescimab in non-small cell lung cancer (NSCLC), commencing enrollment in 2023 in two multiregional Phase III clinical trials, HARMONi and HARMONi-3. In early 2025, the Company began enrolling patients in the United States for HARMONi-7. Summit intends to open clinical trial sites in the United States for the Phase III study in colorectal cancer (CRC) by the end of 2025.

HARMONi is a Phase III clinical trial which intends to evaluate ivonescimab combined with chemotherapy compared to placebo plus chemotherapy in patients with EGFR-mutated, locally advanced or metastatic non-squamous NSCLC who were previously treated with a 3rd generation EGFR TKI (e.g., osimertinib). Enrollment in HARMONi was completed in the second half of 2024, top-line results were announced in May of 2025, with detailed results provided in September 2025.

HARMONi-3 is a Phase III clinical trial which is intended to evaluate ivonescimab combined with chemotherapy compared to pembrolizumab combined with chemotherapy in patients with first-line metastatic, squamous or non-squamous NSCLC, irrespective of PD-L1 expression.

HARMONi-7 is a Phase III clinical trial which is intended to evaluate ivonescimab monotherapy compared to pembrolizumab monotherapy in patients with first-line metastatic NSCLC whose tumors have high PD-L1 expression.

HARMONi-GI3 is a planned Phase III clinical trial evaluating ivonescimab in combination with chemotherapy compared with bevacizumab plus chemotherapy in patients with first-line unresectable metastatic CRC.

In addition, Akeso has recently had positive read-outs in three single-region (China), randomized Phase III clinical trials for ivonescimab in NSCLC: HARMONi-A, HARMONi-2, and HARMONi-6.

HARMONi-A was a Phase III clinical trial which evaluated ivonescimab combined with chemotherapy compared to placebo plus chemotherapy in patients with EGFR-mutated, locally advanced or metastatic non-squamous NSCLC who have progressed after treatment with an EGFR TKI.

HARMONi-2 is a Phase III clinical trial evaluating monotherapy ivonescimab against monotherapy pembrolizumab in patients with locally advanced or metastatic NSCLC whose tumors have positive PD-L1 expression.

HARMONi-6 is a Phase III clinical trial evaluating ivonescimab in combination with platinum-based chemotherapy compared with tislelizumab, an anti-PD-1 antibody, in combination with platinum-based chemotherapy in patients with locally advanced or metastatic squamous NSCLC, irrespective of PD-L1 expression.

Akeso is actively conducting multiple Phase III clinical studies in settings outside of NSCLC, including biliary tract cancer, colorectal cancer, breast cancer, pancreatic cancer, small cell lung cancer, and head and neck cancer.

Ivonescimab is an investigational therapy that is not approved by any regulatory authority in Summit’s license territories, including the United States and Europe. Ivonescimab was initially approved for marketing authorization in China in May 2024. Ivonescimab was granted Fast Track designation by the US Food & Drug Administration (FDA) for the HARMONi clinical trial setting.

(Press release, Summit Therapeutics, OCT 17, 2025, View Source [SID1234656762])

Libtayo® (cemiplimab) Recommended for EU Approval by the CHMP for Adjuvant Treatment of Cutaneous Squamous Cell Carcinoma (CSCC) with a High Risk of Recurrence After Surgery and Radiation

On October 17, 2025 Regeneron Pharmaceuticals, Inc. (NASDAQ: REGN) reported that the European Medicines Agency’s (EMA) Committee for Medicinal Products for Human Use (CHMP) has adopted a positive opinion for Libtayo (cemiplimab) as an adjuvant treatment for adult patients with cutaneous squamous cell carcinoma (CSCC) at high risk of recurrence after surgery and radiation. The European Commission is expected to make a final decision on the application in the coming months. Libtayo was approved by the U.S. Food and Drug Administration (FDA) for these patients in the U.S. earlier this month.

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The positive opinion is supported by results from the global Phase 3 C-POST trial investigating adjuvant Libtayo versus placebo in patients with CSCC at high risk of recurrence following surgery and radiation. In the trial, Libtayo reduced the risk of disease recurrence or death by 68% compared to placebo (hazard ratio [HR]: 0.32; 95% confidence interval [CI]: 0.20-0.51; p<0.0001). Fewer patients treated with Libtayo had locoregional or distant recurrence compared with those who received placebo (4% vs. 17% and 5% vs. 13%, respectively). Detailed data were published in the New England Journal of Medicine (NEJM) in May 2025.

The safety profile of Libtayo as adjuvant treatment of patients with CSCC at high risk of recurrence after surgery and radiation is consistent with the known safety profile for Libtayo monotherapy in advanced cancers. In the trial, adverse events (AEs) occurred in 91% of patients receiving Libtayo (n=205) and 89% of patients receiving placebo (n=204). Grade ≥3 AEs occurred in 24% and 14% of patients in the Libtayo arm and the placebo arm, respectively. The most common AEs occurring in at least 10% of patients who received Libtayo were fatigue, pruritus, rash, diarrhea, arthralgia, hypothyroidism and maculo-papular rash. The only grade ≥3 AE that occurred in more than 2% of patients in the Libtayo arm was hypertension. AEs led to permanent discontinuation of treatment in 10% of patients who received Libtayo and 2% of patients who received placebo. Two patients in each arm experienced an AE leading to death.

About the Phase 3 Trial
C-POST was a randomized, placebo-controlled, double-blind, multicenter, global Phase 3 trial investigating Libtayo versus placebo as adjuvant treatment for patients with features associated with a high risk of CSCC recurrence and who had completed surgery and post-operative radiation therapy. Trial participants were at high risk of recurrence due to nodal features (extracapsular extension or ≥3 involved lymph nodes) and/or non-nodal features (in-transit metastases, T4 lesion, perineural invasion, or locally recurrent tumor with ≥1 additional poor prognostic features).

The trial enrolled 415 patients who were randomized to receive either Libtayo (n=209) or placebo (n=206) for up to 48 weeks. For the first 12 weeks, Libtayo 350 mg or placebo was administered intravenously every three weeks, followed by Libtayo 700 mg or placebo administered intravenously every six weeks for 36 weeks.

About CSCC
Cutaneous squamous cell carcinoma (CSCC) is a type of non-melanoma skin cancer (NMSC), and one of the most common cancers in the world. In the EU, the incidence of NMSC overall is expected to increase by 40% by 2040. CSCC can often be treated successfully with surgery, but many patients may have a "high risk" form that is more aggressive, and they face an increased risk of recurrence and disease progression.

(Press release, Regeneron, OCT 17, 2025, View Source [SID1234656777])

Corvus Pharmaceuticals Announces Presentation of Interim Data from the Phase 1b/2 Clinical Trial of Ciforadenant for Patients with Metastatic Renal Cell Cancer at the European Society for Medical Oncology (ESMO) Congress 2025

On October 17, 2025 Corvus Pharmaceuticals, Inc. (Nasdaq: CRVS), a clinical-stage biopharmaceutical company, reported that interim data from the Phase 1b/2 clinical trial of ciforadenant for patients with metastatic renal cell cancer (RCC) will be presented today in an oral presentation at the European Society for Medical Oncology (ESMO) (Free ESMO Whitepaper) Congress 2025, which is taking place October 17-21, 2025 in Berlin, Germany. The data will be presented by Katy Beckermann, M.D., Ph.D., Director of Genitourinary Cancer Research at Tennessee Oncology and member of the Kidney Cancer Research Consortium (KCRC), the group that is conducting the trial in collaboration with Corvus.

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"We are encouraged by these results exploring ciforadenant in combination with ipilimumab and nivolumab as a potential front-line treatment for renal cell carcinoma," said Richard A. Miller, M.D., co-founder, president and chief executive officer of Corvus. "Despite enrolling patients with more unfavorable disease compared to historical trials, the triplet combination demonstrated activity that compares favorably to historical results with the doublet alone. These data support our view that blocking adenosine signaling with ciforadenant may provide meaningful benefit for RCC patients. We appreciate the partnership with the Kidney Cancer Research Consortium and we look forward to continuing to follow the 19 patients who remain on therapy to better understand the potential of this approach."

The open-label Phase 1b/2 clinical trial is evaluating ciforadenant, the Company’s adenosine A2a receptor inhibitor, as a potential first line therapy for metastatic RCC in combination with ipilimumab (anti-CTLA-4) and nivolumab (anti-PD-1). The trial enrolled 50 patients (8 in Phase 1b portion, 42 in Phase 2 portion) with newly diagnosed or recurrent stage IV clear cell RCC that had not received any prior systemic therapy. Patients received ciforadenant 100 mg oral, twice-daily in combination with ipilimumab (anti-CTLA-4) 1mg/kg given once every three weeks for twelve weeks (4 doses) and nivolumab (anti-PD-1) 3mg/kg given once every three weeks.

The primary endpoint for the Phase 1b portion is safety, tolerability and anti-tumor response. The primary endpoint for the Phase 2 portion is the percent of patients that achieve a deep response, defined as complete response or depth of partial response of >50% tumor volume reduction. Historical data from the Kidney Cancer Research Consortium has shown that deep responses correlate with prolonged progression free survival and that they occur in approximately 32% of patients receiving ipilimumab and nivolumab. Secondary endpoints for the Phase 2 portion include objective response rate (ORR), progression-free survival (PFS) and treatment-related adverse events.

The interim data being presented at ESMO (Free ESMO Whitepaper) demonstrates that triplet therapy with ciforadenant, ipilimumab and nivolumab is feasible and well tolerated. Key highlights from the presentation (data as of May 2025) include:

Patients in the trial had a median age of 61.5 years (53-70 years range) and had unfavorable disease characteristics, with only 54% having a prior nephrectomy (~75-85% is typical for studies involving similar patients). Nephrectomy is associated with improved outcomes in advanced RCC and is often not performed in patients with poor prognosis. In addition, 82% of patients in the trial had a poor or intermediate prognosis by International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) criteria.
The treatment was well-tolerated, in-line with the safety profile of combination treatment with ipilimumab and nivolumab.
The deep response rate was 34%, demonstrating an improvement compared to historical data for the combination of ipilimumab and nivolumab alone, though not statistically significant at this point in time. 19 patients with stable or responding disease remain on therapy with the potential to achieve deep responses.
The ORR by was 46%, including two complete responses and 21 partial responses. The median PFS is 11.04 months.
Dr. Beckermann commented, "Early results from this trial are encouraging, demonstrating consistent efficacy and favorable safety in a challenging RCC population, and we look forward to data from the 19 patients still on treatment."

(Press release, Corvus Pharmaceuticals, OCT 17, 2025, View Source [SID1234656730])

Pimicotinib Treatment Demonstrates Deep and Durable Tumor Responses and Continued Improvements in Pain and Function for Patients with TGCT

On October 17, 2025 Merck, a leading science and technology company, reported the presentation of longer-term results from the global Phase 3 MANEUVER trial evaluating pimicotinib, an investigational colony stimulating factor-1 receptor (CSF-1R) inhibitor in development by Abbisko Therapeutics Co., Ltd., for the treatment of patients with tenosynovial giant cell tumor (TGCT). This latest analysis showed that, with a median follow-up of 14.3 months, the objective response rate (ORR) for people treated with pimicotinib from the beginning of the study increased considerably to 76.2% (95% CI: 63.8, 86.0) by blinded independent review committee (BICR) per RECIST v1.1, from 54% at Week 25. The study also showed continued clinically meaningful improvements in key secondary endpoints related to patient outcomes such as pain and function. The safety profile was consistent with previously reported data. The results are being presented today in the Sarcoma mini-oral session at the European Society for Medical Oncology (ESMO) (Free ESMO Whitepaper) Congress 2025 (Presentation # 2690MO).

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"With the initial results of the global MANEUVER study presented earlier this year at ASCO (Free ASCO Whitepaper), pimicotinib demonstrated the highest objective response rate seen in a Phase 3 clinical trial of a systemic therapy in TGCT," said Prof. Niu Xiaohui, Director of the Bone and Soft Tissue Tumour Diagnosis and Research Centre at Beijing Jishuitan Hospital. "These latest findings build on those impressive results, showing that these tumor responses not only persist but deepen over time. Importantly, we also see continued improvements beyond one year in the patient-reported symptoms and functional outcomes that truly make a difference in patients’ abilities to go about their daily lives. Together, these findings indicate the potential for pimicotinib to be a best-in-class systemic treatment for patients with TGCT."

"TGCT causes pain, stiffness, and loss of range of motion, affecting patients’ ability to participate in activities of daily living and with their families or communities. Ultimately, this affects everyone and takes a mental and physical toll," said Sydney Stern, PhD, MS, TGCT Support, a Program of the Life Raft Group. "Patients benefit from more options that address their symptoms and shrink the disease. Importantly, addressing their symptoms enables patients to be the parents, partners, carers, and people they want to be without wondering when their TGCT will take over their life again."

The latest analysis of the global Phase 3 MANEUVER trial includes results from 63 patients who received pimicotinib for 24 weeks in Part 1 and then continued on pimicotinib in the open-label phase of the trial. With a median follow-up of 14.3 months, tumor responses continued to improve:

ORR per BIRC based on RECIST v1.1 increased to 76.2% (95% CI: 63.8, 86.0), from 54% at Week 25.
ORR per BIRC based on tumor volume score (TVS), an endpoint designed specifically for TGCT, increased to 74.6% (95% CI: 62.1, 84.7), from 61.9% at Week 25.
At the time of the data cutoff, the median duration of response was not reached (range: 0.03-19.81 months), with 93.7% of pimicotinib-treated patients experiencing a reduction in tumor size by BIRC per RECIST v1.1 at longer-term follow up.
Pimicotinib also demonstrated clinically meaningful improvements with longer-term follow-up up to week 73 in key patient-reported measures including range of motion, pain, stiffness and physical function that significantly impact people living with TGCT:

For relative range of motion, pimicotinib showed a mean change from baseline of 23.9% (increased from 15.6% at week 25).
Mean change from baseline continued to show improvements in physical function as measured by the patient-reported PROMIS-PF scale, and reductions in stiffness and pain as measured by the Worst Stiffness Numeric Scale Rating and Brief Pain Inventory worst pain rating, respectively.
The analysis also includes results for patients who were initially randomized to receive placebo in Part 1, then switched to pimicotinib in the open label part of the study (n=31). These patients experienced a clear benefit from pimicotinib treatment, with an ORR of 64.5% both by BICR per RECIST v1.1 and by TVS with a median follow-up of 8.5 months after switching to pimicotinib.

At longer-term follow-up, in patients who had received pimicotinib throughout the study, there were no new safety signals, and no evidence of cholestatic hepatotoxicity, drug-induced liver injury or hair/skin hypopigmentation. Most treatment-emergent adverse events remained mild in severity and were manageable.

"These longer-term results highlight the potential of pimicotinib to transform care by providing a systemic therapy that delivers meaningful, lasting benefit not only in terms of reducing tumor burden but in helping patients regain function and live with reduced pain," said Victoria Zazulina, M.D., Head of Development Unit, Oncology, Healthcare business of Merck. "Guided by this robust global study—conducted across North America, Europe and China—we are working with regulatory authorities as we seek to make this treatment available to patients as quickly as possible."

An application for marketing authorization of pimicotinib as a Class 1 innovative drug for adult patients with TGCT has been accepted for review by the Center for Drug Evaluation (CDE) of the China National Medical Products Administration (NMPA). Additional applications are planned in the U.S. and other markets around the world.

About MANEUVER

The pivotal global Phase 3 MANEUVER study is a three-part, randomized, double-blind, placebo-controlled study to assess the efficacy and safety of pimicotinib in patients with TGCT who require systemic therapy and have not received prior anti-CSF-1/CSF-1R therapy. The study is being conducted by Abbisko Therapeutics in China (n=45), Europe (n=28), and the U.S. and Canada (n=21).

In the double-blind Part 1, 94 patients were randomized 2:1 to receive either 50 mg QD of pimicotinib (n=63) or placebo (n=31) for 24 weeks. The primary endpoint was objective response rate (ORR) at week 25, as measured by Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1 by blinded independent central review (BICR) in the intent-to-treat (ITT) population. Secondary endpoints include tumor volume score (TVS), relative range of motion, stiffness by Numeric Rating Scale (NRS), pain by Brief Pain Inventory (BPI), and physical function measured by Patient-Reported Outcomes Measurement Information System (PROMIS-PF).

After the double-blind Part 1, eligible patients could continue to the open-label Part 2 for up to 24 weeks of further treatment. Patients who completed Part 2 could then enter the open-label extension phase (Part 3) for extended treatment and safety follow-up.

About Pimicotinib (ABSK021)

Pimicotinib (ABSK021), which is being developed by Abbisko Therapeutics, is a novel, orally administered, highly selective and potent small-molecule inhibitor of CSF-1R. Pimicotinib has been granted breakthrough therapy designation (BTD) for the treatment of inoperable TGCT by China National Medical Products Administration (NMPA) and the U.S. Food and Drug Administration (FDA), and priority medicine (PRIME) designation from the European Medicines Agency (EMA). Merck holds worldwide commercialization rights for pimicotinib.

Advancing the Future of Cancer Care

At Merck, we strive every day to improve the futures of people living with cancer. Building on our 350-year global heritage as pharma pioneers, we are focusing our most promising science to target cancer’s deepest vulnerabilities, pursuing differentiated molecules to strike cancer at its core. By developing new therapies that can help advance cancer care, we are determined to create a world where more cancer patients will become cancer survivors. Learn more at www.merckgroup.com.

(Press release, Merck & Co, OCT 17, 2025, View Source [SID1234656763])

Lilly’s Verzenio® (abemaciclib) prolonged survival in HR+, HER2-, high-risk early breast cancer with two years of treatment

On October 17, 2025 Eli Lilly and Company (NYSE: LLY) reported results from the primary overall survival (OS) analysis of the Phase 3 monarchE trial showing that two years of adjuvant Verzenio plus endocrine therapy (ET) reduced the risk of death by 15.8% versus ET alone and resulted in sustained long-term improvements in invasive disease-free survival (IDFS) and distant relapse-free survival (DRFS), in patients with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-), node-positive, high-risk early breast cancer.

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These results were published in the Annals of Oncology and will be shared in a late-breaking oral presentation at the ESMO (Free ESMO Whitepaper) Annual Meeting today, Friday, October 17, at 2:50 PM CEST/08:50 AM ET in Berlin, Germany. These data are being submitted to regulatory health authorities globally.

"For patients, survival is what matters most — and abemaciclib plus endocrine therapy represents the first contemporary medicine in over two decades to deliver a clear improvement in overall survival in the adjuvant setting," said Stephen Johnston, M.D., Ph.D., Professor of Breast Cancer Medicine and Consultant Medical Oncologist at The Royal Marsden NHS Foundation Trust (London, U.K.) and lead investigator for monarchE. "These results represent an important step forward in the treatment of high-risk HR+, HER2− early breast cancer."

The data presented include results from the primary OS analysis reflecting a median follow-up of 6.3 years, with more than 75% of patients having been followed for at least four years after completion of the two-year Verzenio treatment period. In the intent-to-treat (ITT) population, Verzenio plus ET reduced the risk of death by 15.8% compared to ET alone [7-year overall survival (OS) rate: 86.8% vs. 85.0%; hazard ratio (HR) 0.842; 95% CI: 0.722–0.981; 2-sided p=0.027].

In addition, treatment with Verzenio plus ET led to a sustained reduction in risk of recurrence at seven years, continuing to demonstrate the deep IDFS and DRFS benefit and carryover effect previously seen at five years in monarchE. Notably, 32% fewer patients treated with Verzenio plus ET were living with metastatic disease compared to those receiving ET alone (6.4% vs 9.4%, respectively). Continued long-term follow-up from this trial will help to determine whether this ongoing difference in patients alive with metastatic disease translates into further deepening of survival benefit with time. Results for Cohort 1 were consistent with those for the ITT population across OS, IDFS and DRFS results, and the benefit was also demonstrated across subgroups.

"These results represent an important advancement in the care of node-positive, high-risk HR+, HER2- disease by delivering meaningful reductions in recurrence and improving survival," said Jacob Van Naarden, executive vice president and president of Lilly Oncology. "These findings reinforce two years of Verzenio plus endocrine therapy as the standard of care for node-positive, high-risk disease, offering renewed hope for patients facing this diagnosis."

Safety findings were consistent with the known profile of Verzenio and prior monarchE analyses. No new safety signals or delayed toxicities were observed. Adverse events were generally managed with dose modifications, consistent with prior monarchE analyses.

"For patients facing high-risk early breast cancer, these results are meaningful," said Sue Weldon, CEO of Unite for HER. "To now have data showing a treatment helps more people live longer is a major step forward for our community. We mark this significant milestone while recognizing there’s more work ahead to ensure every eligible patient has the opportunity to benefit from treatments that can change lives."

About the monarchE Study
monarchE was a global, randomized, open-label, two cohort, multicenter Phase 3 clinical trial that enrolled 5,637 adults with HR+, HER2-, node-positive EBC at high risk of recurrence. The study enrolled patients across more than 600 sites in 38 countries and is the only adjuvant study designed to investigate a CDK4/6 inhibitor specifically in a node-positive, high-risk EBC population. To be enrolled in Cohort 1 (n=5,120), which is the FDA-approved population, patients had to have 4+ positive nodes or 1-3 positive nodes and at least one of the following: tumors that were ≥5 cm or Grade 3. Patients enrolled in Cohort 2 could not have met the eligibility criteria for Cohort 1. To be enrolled in Cohort 2 (n=517), patients had to have 1-3 positive nodes and Ki-67 score ≥20%. Patients in each cohort were randomized 1:1 to receive either Verzenio 150 mg twice daily plus standard-of-care adjuvant ET (Cohort 1, n=2,555; Cohort 2, n=253) or standard-of-care adjuvant ET alone (Cohort 1, n=2,565; Cohort 2, n=264) for 2 years. ET continued for at least 5 years if deemed medically appropriate. The primary endpoint was IDFS. Consistent with expert guidelines, IDFS was defined as the length of time before breast cancer comes back, any new cancer develops, or death. OS was a key secondary endpoint in monarchE. The OS analysis plan was amended after the primary analysis of IDFS, following consultation with regulators, to increase the number of required OS events from 390 to 650 to ensure a minimum follow-up of at least 5 years and enable a more mature survival dataset.1,2

About Early Breast Cancer and Risk of Recurrence
It is estimated that 90% of all breast cancers are detected at an early stage.3 Approximately 70% of all breast cancer cases are the HR+, HER2- subtype.4 Although the prognosis for HR+, HER2- EBC is generally favorable, high-risk patients are three times more likely than those with low risk characteristics to experience recurrence – with the majority being incurable metastatic disease.5 These patients have an increased risk of recurrence during the first two years of endocrine therapy.

Factors associated with high-risk of recurrence in HR+, HER2- early breast cancer include: positive nodal status, the number of positive nodes, large tumor size (≥5 cm), and high tumor grade (Grade 3). Node-positive means that cancer cells from the tumor in the breast have been found in the lymph nodes near the breast. Although breast cancer is removed through surgery, the presence of cancer cells in the lymph nodes signifies that there is a higher chance of developing recurrence and distant metastatic disease.

About Breast Cancer
Breast cancer is the second most commonly diagnosed cancer worldwide (following lung cancer), according to GLOBOCAN. The estimated 2.3 million new cases indicate that close to 1 in every 4 cancers diagnosed in 2022 is breast cancer. With approximately 666,000 deaths in 2022, breast cancer is the fourth-leading cause of cancer death worldwide.6 In the U.S., it is estimated that there will be more than 310,000 new cases of breast cancer diagnosed in 2024. Breast cancer is the second leading cause of cancer death in women in the U.S.7

About Verzenio (abemaciclib)
Verzenio (abemaciclib) is approved to treat people with certain HR+, HER2- breast cancers in the adjuvant and advanced or metastatic setting. Verzenio is the first CDK4/6 inhibitor approved to treat node-positive, high-risk early breast cancer (EBC) patients.8 For HR+, HER2- breast cancer, The National Comprehensive Cancer Network (NCCN) recommends consideration of two years of abemaciclib (Verzenio) added to endocrine therapy as a Category 1 treatment option in the adjuvant setting.9 NCCN also includes Verzenio plus endocrine therapy as a preferred treatment option for HR+, HER2- metastatic breast cancer.9

The collective results of Lilly’s clinical development program continue to differentiate Verzenio as a CDK4/6 inhibitor. In high-risk EBC, Verzenio has shown a persistent and deepening benefit beyond the two-year treatment period in the monarchE trial, an adjuvant study designed specifically to investigate a CDK4/6 inhibitor in a node-positive, high-risk EBC population.10 In metastatic breast cancer, Verzenio has demonstrated statistically significant OS in the Phase 3 MONARCH 2 study.11 Verzenio has shown a consistent and generally manageable safety profile across clinical trials.

Verzenio is an oral tablet taken twice daily and available in strengths of 50 mg, 100 mg, 150 mg, and 200 mg. Discovered and developed by Lilly researchers, Verzenio was first approved in 2017 and is currently authorized for use in more than 90 counties around the world. For full details on indicated uses of Verzenio in HR+, HER2- breast cancer, please see full Prescribing Information, available at www.Verzenio.com.

INDICATIONS FOR VERZENIO
VERZENIO is a kinase inhibitor indicated:

in combination with endocrine therapy (tamoxifen or an aromatase inhibitor) for the adjuvant treatment of adult patients with hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative, node-positive, early breast cancer at high risk of recurrence.
in combination with an aromatase inhibitor as initial endocrine-based therapy for the treatment of adult patients with hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative advanced or metastatic breast cancer.
in combination with fulvestrant for the treatment of adult patients with hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative advanced or metastatic breast cancer with disease progression following endocrine therapy.
as monotherapy for the treatment of adult patients with HR-positive, HER2-negative advanced or metastatic breast cancer with disease progression following endocrine therapy and prior chemotherapy in the metastatic setting.
IMPORTANT SAFETY INFORMATION FOR VERZENIO (abemaciclib)
Severe diarrhea associated with dehydration and infection occurred in patients treated with Verzenio. Across four clinical trials in 3691 patients, diarrhea occurred in 81 to 90% of patients who received Verzenio. Grade 3 diarrhea occurred in 8 to 20% of patients receiving Verzenio. Most patients experienced diarrhea during the first month of Verzenio treatment. The median time to onset of the first diarrhea event ranged from 6 to 8 days; and the median duration of Grade 2 and Grade 3 diarrhea ranged from 6 to 11 days and 5 to 8 days, respectively. Across trials, 19 to 26% of patients with diarrhea required a Verzenio dose interruption and 13 to 23% required a dose reduction.

Instruct patients to start antidiarrheal therapy, such as loperamide, at the first sign of loose stools, increase oral fluids, and notify their healthcare provider for further instructions and appropriate follow-up. For Grade 3 or 4 diarrhea, or diarrhea that requires hospitalization, discontinue Verzenio until toxicity resolves to ≤Grade 1, and then resume Verzenio at the next lower dose.

Neutropenia, including febrile neutropenia and fatal neutropenic sepsis, occurred in patients treated with Verzenio. Across four clinical trials in 3691 patients, neutropenia occurred in 37 to 46% of patients receiving Verzenio. A Grade ≥3 decrease in neutrophil count (based on laboratory findings) occurred in 19 to 32% of patients receiving Verzenio. Across trials, the median time to first episode of Grade ≥3 neutropenia ranged from 29 to 33 days, and the median duration of Grade ≥3 neutropenia ranged from 11 to 16 days. Febrile neutropenia has been reported in <1% of patients exposed to Verzenio across trials. Two deaths due to neutropenic sepsis were observed in MONARCH 2. Inform patients to promptly report any episodes of fever to their healthcare provider.

Monitor complete blood counts prior to the start of Verzenio therapy, every 2 weeks for the first 2 months, monthly for the next 2 months, and as clinically indicated. Dose interruption, dose reduction, or delay in starting treatment cycles is recommended for patients who develop Grade 3 or 4 neutropenia.

Severe, life-threatening, or fatal interstitial lung disease (ILD) or pneumonitis can occur in patients treated with Verzenio and other CDK4/6 inhibitors. In Verzenio-treated patients in EBC (monarchE), 3% of patients experienced ILD or pneumonitis of any grade: 0.4% were Grade 3 or 4 and there was one fatality (0.1%). In Verzenio-treated patients in MBC (MONARCH 1, MONARCH 2, MONARCH 3), 3.3% of Verzenio-treated patients had ILD or pneumonitis of any grade: 0.6% had Grade 3 or 4, and 0.4% had fatal outcomes. Additional cases of ILD or pneumonitis have been observed in the postmarketing setting, with fatalities reported.

Monitor patients for pulmonary symptoms indicative of ILD or pneumonitis. Symptoms may include hypoxia, cough, dyspnea, or interstitial infiltrates on radiologic exams. Infectious, neoplastic, and other causes for such symptoms should be excluded by means of appropriate investigations. Dose interruption or dose reduction is recommended in patients who develop persistent or recurrent Grade 2 ILD or pneumonitis. Permanently discontinue Verzenio in all patients with Grade 3 or 4 ILD or pneumonitis.

Grade ≥ 3 increases in alanine aminotransferase (ALT) (2 to 6%) and aspartate aminotransferase (AST) (2 to 3%) were reported in patients receiving Verzenio. Across three clinical trials in 3559 patients (monarchE, MONARCH 2, MONARCH 3), the median time to onset of Grade ≥3 ALT increases ranged from 57 to 87 days and the median time to resolution to Grade <3 was 13 to 14 days. The median time to onset of Grade ≥3 AST increases ranged from 71 to 185 days and the median time to resolution to Grade <3 ranged from 11 to 15 days.

Monitor liver function tests (LFTs) prior to the start of Verzenio therapy, every 2 weeks for the first 2 months, monthly for the next 2 months, and as clinically indicated. Dose interruption, dose reduction, dose discontinuation, or delay in starting treatment cycles is recommended for patients who develop persistent or recurrent Grade 2, or any Grade 3 or 4 hepatic transaminase elevation.

Venous thromboembolic events (VTE) were reported in 2 to 5% of patients across three clinical trials in 3559 patients treated with Verzenio (monarchE, MONARCH 2, MONARCH 3). VTE included deep vein thrombosis, pulmonary embolism, pelvic venous thrombosis, cerebral venous sinus thrombosis, subclavian and axillary vein thrombosis, and inferior vena cava thrombosis. In clinical trials, deaths due to VTE have been reported in patients treated with Verzenio.

Verzenio has not been studied in patients with early breast cancer who had a history of VTE. Monitor patients for signs and symptoms of venous thrombosis and pulmonary embolism and treat as medically appropriate. Dose interruption is recommended for EBC patients with any grade VTE and for MBC patients with a Grade 3 or 4 VTE.

Verzenio can cause fetal harm when administered to a pregnant woman, based on findings from animal studies and the mechanism of action. In animal reproduction studies, administration of abemaciclib to pregnant rats during the period of organogenesis caused teratogenicity and decreased fetal weight at maternal exposures that were similar to the human clinical exposure based on area under the curve (AUC) at the maximum recommended human dose. Advise pregnant women of the potential risk to a fetus. Advise females of reproductive potential to use effective contraception during treatment with Verzenio and for 3 weeks after the last dose. Based on findings in animals, Verzenio may impair fertility in males of reproductive potential. There are no data on the presence of Verzenio in human milk or its effects on the breastfed child or on milk production. Advise lactating women not to breastfeed during Verzenio treatment and for at least 3 weeks after the last dose because of the potential for serious adverse reactions in breastfed infants.

The most common adverse reactions (all grades, ≥10%) observed in monarchE forVerzenio plus tamoxifen or an aromatase inhibitor vs tamoxifen or an aromatase inhibitor, with a difference between arms of ≥2%, were diarrhea (84% vs 9%), infections (51% vs 39%), neutropenia (46% vs 6%), fatigue (41% vs 18%), leukopenia (38% vs 7%), nausea (30% vs 9%), anemia (24% vs 4%), headache (20% vs 15%), vomiting (18% vs 4.6%), stomatitis (14% vs 5%), lymphopenia (14% vs 3%), thrombocytopenia (13% vs 2%), decreased appetite (12% vs 2.4%), ALT increased (12% vs 6%), AST increased (12% vs 5%), dizziness (11% vs 7%), rash (11% vs 4.5%), and alopecia (11% vs 2.7%).

The most frequently reported ≥5% Grade 3 or 4 adverse reaction that occurred in the Verzenio arm vs the tamoxifen or an aromatase inhibitor arm of monarchE were neutropenia (19.6% vs 1%), leukopenia (11% vs <1%), diarrhea (8% vs 0.2%), and lymphopenia (5% vs <1%).

Lab abnormalities (all grades; Grade 3 or 4) for monarchE in ≥10% for Verzenio plus tamoxifen or an aromatase inhibitor with a difference between arms of ≥2% were increased serum creatinine (99% vs 91%; 0.5% vs <0.1%), decreased white blood cells (89% vs 28%; 19.1% vs 1.1%), decreased neutrophil count (84% vs 23%; 18.7% vs 1.9%), anemia (68% vs 17%; 1% vs .1%), decreased lymphocyte count (59% vs 24%; 13.2 % vs 2.5%), decreased platelet count (37% vs 10%; .9% vs .2%), increased ALT (37% vs 24%; 2.6% vs 1.2%), increased AST (31% vs 18%; 1.6% vs .9%), and hypokalemia (11% vs 3.8%; 1.3% vs 0.2%).

The most common adverse reactions (all grades, ≥10%) observed in MONARCH 3 for Verzenio plus anastrozole or letrozole vs anastrozole or letrozole, with a difference between arms of ≥2%, were diarrhea (81% vs 30%), fatigue (40% vs 32%), neutropenia (41% vs 2%), infections (39% vs 29%), nausea (39% vs 20%), abdominal pain (29% vs 12%), vomiting (28% vs 12%), anemia (28% vs 5%), alopecia (27% vs 11%), decreased appetite (24% vs 9%), leukopenia (21% vs 2%), creatinine increased (19% vs 4%), constipation (16% vs 12%), ALT increased (16% vs 7%), AST increased (15% vs 7%), rash (14% vs 5%), pruritus (13% vs 9%), cough (13% vs 9%), dyspnea (12% vs 6%), dizziness (11% vs 9%), weight decreased (10% vs 3.1%), influenza-like illness (10% vs 8%), and thrombocytopenia (10% vs 2%).

The most frequently reported ≥5% Grade 3 or 4 adverse reactions that occurred in the Verzenio arm vs the placebo arm of MONARCH 3 were neutropenia (22% vs 1%), diarrhea (9% vs 1.2%), leukopenia (7% vs <1%)), increased ALT (6% vs 2%), and anemia (6% vs 1%).

Lab abnormalities (all grades; Grade 3 or 4) for MONARCH 3 in ≥10% for Verzenio plus anastrozole or letrozole with a difference between arms of ≥2% were increased serum creatinine (98% vs 84%; 2.2% vs 0%), decreased white blood cells (82% vs 27%; 13% vs 0.6%), anemia (82% vs 28%; 1.6% vs 0%), decreased neutrophil count (80% vs 21%; 21.9% vs 2.6%), decreased lymphocyte count (53% vs 26%; 7.6% vs 1.9%), decreased platelet count (36% vs 12%; 1.9% vs 0.6%), increased ALT (48% vs 25%; 6.6% vs 1.9%), and increased AST (37% vs 23%; 3.8% vs 0.6%).

The most common adverse reactions (all grades, ≥10%) observed in MONARCH 2 for Verzenio plus fulvestrant vs fulvestrant, with a difference between arms of ≥2%, were diarrhea (86% vs 25%), neutropenia (46% vs 4%), fatigue (46% vs 32%), nausea (45% vs 23%), infections (43% vs 25%), abdominal pain (35% vs 16%), anemia (29% vs 4%), leukopenia (28% vs 2%), decreased appetite (27% vs 12%), vomiting (26% vs 10%), headache (20% vs 15%), dysgeusia (18% vs 2.7%), thrombocytopenia (16% vs 3%), alopecia (16% vs 1.8%), stomatitis (15% vs 10%), ALT increased (13% vs 5%), pruritus (13% vs 6%), cough (13% vs 11%), dizziness (12% vs 6%), AST increased (12% vs 7%), peripheral edema (12% vs 7%), creatinine increased (12% vs <1%), rash (11% vs 4.5%), pyrexia (11% vs 6%), and weight decreased (10% vs 2.2%).

The most frequently reported ≥5% Grade 3 or 4 adverse reactions that occurred in the Verzenio arm vs the placebo arm of MONARCH 2 were neutropenia (25% vs 1%), diarrhea (13% vs 0.4%), leukopenia (9% vs 0%), anemia (7% vs 1%), and infections (5.7% vs 3.5%).

Lab abnormalities (all grades; Grade 3 or 4) for MONARCH 2 in ≥10% for Verzenio plus fulvestrant with a difference between arms of ≥2% were increased serum creatinine (98% vs 74%; 1.2% vs 0%), decreased white blood cells (90% vs 33%; 23.7% vs .9%), decreased neutrophil count (87% vs 30%; 32.5% vs 4.2%), anemia (84% vs 34%; 2.6% vs .5%), decreased lymphocyte count (63% vs 32%; 12.2% vs 1.8%), decreased platelet count (53% vs 15%; 2.1% vs 0%), increased ALT (41% vs 32%; 4.6% vs 1.4%), and increased AST (37% vs 25%; 3.9% vs 4.2%).

The most common adverse reactions (all grades, ≥10%) observed in MONARCH 1 with Verzenio were diarrhea (90%), fatigue (65%), nausea (64%), decreased appetite (45%), abdominal pain (39%), neutropenia (37%), vomiting (35%), infections (31%), anemia (25%), thrombocytopenia (20%), headache (20%), cough (19%), constipation (17%), leukopenia (17%), arthralgia (15%), dry mouth (14%), weight decreased (14%), stomatitis (14%), creatinine increased (13%), alopecia (12%), dysgeusia (12%), pyrexia (11%), dizziness (11%), and dehydration (10%).

The most frequently reported ≥5% Grade 3 or 4 adverse reactions from MONARCH 1 with Verzenio were diarrhea (20%), neutropenia (24%), fatigue (13%), and leukopenia (5%).

Lab abnormalities (all grades; Grade 3 or 4) for MONARCH 1 with Verzenio were increased serum creatinine (99%; .8%), decreased white blood cells (91%; 28%), decreased neutrophil count (88%; 26.6%), anemia (69%; 0%), decreased lymphocyte count (42%; 13.8%), decreased platelet count (41%; 2.3%), increased ALT (31%; 3.1%), and increased AST (30%; 3.8%).

Strong and moderate CYP3A inhibitors increased the exposure of abemaciclib plus its active metabolites to a clinically meaningful extent and may lead to increased toxicity. Avoid concomitant use of ketoconazole. Ketoconazole is predicted to increase the AUC of abemaciclib by up to 16-fold. In patients with recommended starting doses of 200 mg twice daily or 150 mg twice daily, reduce the Verzenio dose to 100 mg twice daily with concomitant use of strong CYP3A inhibitors other than ketoconazole. In patients who have had a dose reduction to 100 mg twice daily due to adverse reactions, further reduce the Verzenio dose to 50 mg twice daily with concomitant use of strong CYP3A inhibitors. If a patient taking Verzenio discontinues a strong CYP3A inhibitor, increase the Verzenio dose (after 3 to 5 half-lives of the inhibitor) to the dose that was used before starting the inhibitor. With concomitant use of moderate CYP3A inhibitors, monitor for adverse reactions and consider reducing the Verzenio dose in 50 mg decrements. Patients should avoid grapefruit products.

Avoid concomitant use of strong or moderate CYP3A inducers and consider alternative agents. Coadministration of strong or moderate CYP3A inducers decreased the plasma concentrations of abemaciclib plus its active metabolites and may lead to reduced activity.

With severe hepatic impairment (Child-Pugh C), reduce the Verzenio dosing frequency to once daily. The pharmacokinetics of Verzenio in patients with severe renal impairment (CLcr <30 mL/min), end stage renal disease, or in patients on dialysis is unknown. No dosage adjustments are necessary in patients with mild or moderate hepatic (Child-Pugh A or B) and/or renal impairment (CLcr ≥30-89 mL/min).

(Press release, Eli Lilly, OCT 17, 2025, View Source [SID1234656731])