Enhertu reduced the risk of disease recurrence or death by 53% vs. T-DM1 in patients with high-risk HER2-positive early breast cancer following neoadjuvant therapy in DESTINY-Breast05 Phase III trial

On October 18, 2025 Astrazeneca reported positive results from the DESTINY-Breast05 Phase III trial showed Enhertu (trastuzumab deruxtecan) demonstrated a highly statistically significant and clinically meaningful improvement in invasive disease-free survival (IDFS) in patients with a high risk of disease recurrence. The trial compared Enhertu with trastuzumab emtansine (T-DM1) as a post-neoadjuvant treatment (after surgery) in patients with HER2-positive early breast cancer with residual invasive disease in the breast and/or axillary lymph nodes after neoadjuvant treatment.

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Results showed Enhertu significantly reduced the risk of invasive disease recurrence or death by 53% compared with T-DM1 as a post-neoadjuvant treatment (based on an IDFS hazard ratio [HR] of 0.47, 95% confidence interval [CI] 0.34-0.66, p<0.0001). At three years, 92.4% of patients in the Enhertu arm were alive and free of invasive disease, compared with 83.7% of those in the T-DM1 arm. The IDFS results were consistent across all prespecified subgroups.

Enhertu also significantly reduced the risk of disease recurrence or death (disease-free survival [DFS]), a key secondary endpoint, by 53% (HR 0.47; 95% CI 0.34-0.66; p<0.0001). Further, Enhertu lowered the risk of distant disease recurrence (distant recurrence-free interval [DRFI]) by 51% and the risk of brain metastases (brain metastasis-free interval [BMFI]) by 36% versus T-DM1.

Overall survival (OS) was not mature at the time of this planned interim analysis (2.9% maturity at data cut-off) and will be assessed in future analyses (HR 0.61; 95% CI 0.34-1.10).

Charles Geyer, MD, Chief Scientific Officer of the National Surgical Adjuvant Breast and Bowel Project Foundation (NSABP) Foundation, Professor of Medicine at the UPMC Hillman Cancer Center and principal investigator for the trial, said: "For patients with residual disease after neoadjuvant treatment, the post‑neoadjuvant setting represents a critical second opportunity to reduce recurrence risk, and in DESTINY‑Breast05 Enhertu reduced the risk of early recurrence or death by 53 per cent compared to the current standard of T‑DM1. These results, coupled with the safety data from the trial, are likely to transform clinical practice in the post-neoadjuvant setting for patients with high-risk disease, with the potential for Enhertu to set a new standard of care."

Susan Galbraith, Executive Vice President, Oncology Haematology R&D, AstraZeneca, said: "Progress in treating HER2-positive early breast cancer has been significant, yet managing patients at a higher-risk of recurrence remains challenging. These landmark data, alongside those from DESTINY-Breast11, underscore the potential of Enhertu to become a foundational treatment in early-stage breast cancer, increasing the likelihood that more patients could be cured in this setting."

Ken Takeshita, Global Head, R&D, Daiichi Sankyo, said: "The results of DESTINY-Breast05 demonstrate a clear benefit of Enhertu over the current standard of care in patients with high-risk HER2-positive early breast cancer following surgery, improving their chance for sustained long-term outcomes. These results, coupled with the results of DESTINY-Breast11, illustrate the continued promise of Enhertu to move earlier in the breast cancer treatment paradigm where it can have the greatest impact on the lives of patients."

Summary of Results: DESTINY-Breast05i

Efficacy Measure

Enhertu
(5.4 mg/kg; n=818)

T-DM1
(n=817)

IDFSii

3-year IDFS rate, %

92.4

83.7

HR 0.47 (95% CI 0.34-0.66); p<0.0001

DFSiii

3-year DFS rate, %

92.3

83.5

HR 0.47 (95% CI 0.34-0.66); p<0.0001

DRFIiv

3-year event-free rate, %

93.9

86.1

HR 0.49 (95% CI 0.34-0.71)

BMFIv

3-year event-free rate, %

97.6

95.8

HR 0.64 (95% CI 0.35-1.17)

OSvi

Survival at 3 years, %

97.4

95.7

HR 0.61 (95% CI 0.34-1.10)

TDM-1, trastuzumab emtansine; CI, confidence interval; HR, hazard ratio; IDFS, invasive disease-free survival; DFS, disease-free survival; DRFI, distant recurrence-free interval; BMFI, brain-metastasis-free interval; OS, overall survival

i Data cut-off 2 July 2025
ii IDFS is defined as the time from randomisation until the date of first occurrence of one of the following events: recurrence of ipsilateral invasive breast tumour, recurrence of ipsilateral locoregional invasive breast cancer, contralateral invasive breast cancer, a distant disease recurrence or death from any cause; based on investigator assessment; statistically evaluated using the pre-specified hierarchical testing procedure
iii DFS is defined as the time between randomisation and the date of the first occurrence of an IDFS event per STEEP criteria, including second primary non-breast cancer event, or contralateral or ipsilateral ductal carcinoma in situ (DCIS); based on investigator assessment; statistically evaluated using the pre-specified hierarchical testing procedure
iv DRFI is defined as the time between randomisation and the date of distant breast cancer recurrence; based on investigator assessment
v BMFI is defined as the time between randomisation and the date of documentation of brain metastases or leptomeningeal disease; based on investigator assessment
vi 2.9% maturity

The safety profile of Enhertu observed in DESTINY-Breast05 was consistent with its known profile with no new safety concerns identified. Grade 3 or higher treatment emergent adverse events (AEs) rates were comparable between Enhertu and T-DM1 (50.6% versus 51.9%). Rates of interstitial lung disease (ILD) were low in both arms with ILD events occurring in 9.6% of the Enhertu arm and 1.6% of the T-DM1 arm. The majority of ILD events were low Grade (Grade 1 or 2). There were no Grade 3 or higher ILD events for T-DMI. There were seven Grade 3 events and no Grade 4 events in the Enhertu arm. There were two Grade 5 events in the Enhertu arm as determined by an independent adjudication committee.

The DESTINY-Breast05 results (abstract #LBA1) will be presented today during Presidential Symposium I alongside the results of the DESTINY-Breast11 Phase III trial (abstract #291O) at the European Society for Medical Oncology (ESMO) (Free ESMO Whitepaper) 2025 Congress in Berlin, Germany.

DESTINY-Breast05 was conducted in collaboration with the NSABP, the German Breast Group (GBG), Arbeitsgemeinschaft Gynäkologische Onkologie (AGO-B) and SOLTI Breast Cancer Research Group.

Enhertu is a specifically engineered HER2-directed DXd antibody drug conjugate (ADC) discovered by Daiichi Sankyo and being jointly developed and commercialised by AstraZeneca and Daiichi Sankyo.

Notes

Post neoadjuvant treatment for HER2-positive early breast cancer
Breast cancer is the second most common cancer and one of the leading causes of cancer-related deaths worldwide.1 More than two million breast cancer cases were diagnosed in 2022, with more than 665,000 deaths globally.1

HER2 is a tyrosine kinase receptor growth-promoting protein expressed on the surface of many types of tumours including breast cancer.2 HER2 protein overexpression may occur as a result of HER2 gene amplification and is often associated with aggressive disease and poor prognosis in breast cancer.2 Approximately one in five cases of breast cancer are considered HER2-positive.3

For patients with HER2-positive early breast cancer, achieving pCR with neoadjuvant treatment is the earliest indicator of improved long-term survival.4 However, approximately half of patients who receive neoadjuvant treatment do not reach pCR and have poorer long-term outcomes, putting them at increased risk of disease recurrence.5-9

Post-neoadjuvant therapy represents a key opportunity to minimise the risk of recurrence and prevent progression to metastatic disease for patients with residual disease. Despite receiving additional treatment with T-DMI in the post-neoadjuvant setting, approximately 20% of patients still experience invasive disease or death and no reduction in the risk of CNS recurrence.10,11 Once patients are diagnosed with metastatic disease, the five-year survival rate drops from nearly 90% to approximately 30%.12

New treatment options are needed in the early breast cancer setting to help reduce the likelihood of disease progression and improve long-term outcomes for more patients.

DESTINY-Breast05
DESTINY-Breast05 is a global, multicentre, randomised, open-label, Phase III trial evaluating the efficacy and safety of Enhertu (5.4 mg/kg) versus T-DM1 in patients with HER2-positive early breast cancer with residual invasive disease in breast and/or axillary lymph nodes following neoadjuvant therapy and a high risk of recurrence. High risk of recurrence was defined as presentation with inoperable cancer (prior to neoadjuvant therapy) or pathologically positive axillary lymph nodes following neoadjuvant therapy.

The primary endpoint of DESTINY-Breast05 is investigator-assessed IDFS. IDFS is defined as the time from randomisation until first recurrence, distant recurrence or death from any cause. The key secondary endpoint is investigator-assessed disease-free survival. Other secondary endpoints include OS, distant recurrence-free interval, brain metastases-free interval and safety.

DESTINY-Breast05 enrolled 1,635 patients in Asia, Europe, North America, Oceania and South America. For more information about the trial, visit ClinicalTrials.gov.

Enhertu
Enhertu is a HER2-directed ADC. Designed using Daiichi Sankyo’s proprietary DXd ADC Technology, Enhertu is the lead ADC in the oncology portfolio of Daiichi Sankyo and the most advanced programme in AstraZeneca’s ADC scientific platform. Enhertu consists of a HER2-monoclonal antibody attached to a number of topoisomerase I inhibitor payloads (an exatecan derivative, DXd) via tetrapeptide-based cleavable linkers.

Enhertu (5.4 mg/kg) is approved in more than 85 countries/regions worldwide for the treatment of adult patients with unresectable or metastatic HER2-positive (immunohistochemistry [IHC] 3+ or in-situ hybridisation (ISH)+) breast cancer who have received a prior anti-HER2-based regimen, either in the metastatic setting or in the neoadjuvant or adjuvant setting, and have developed disease recurrence during or within six months of completing therapy based on the results from the DESTINY-Breast03 trial.

Enhertu (5.4 mg/kg) is approved in more than 85 countries/regions worldwide for the treatment of adult patients with unresectable or metastatic HER2-low (IHC 1+ or IHC 2+/ISH-) breast cancer who have received a prior systemic therapy in the metastatic setting or developed disease recurrence during or within six months of completing adjuvant chemotherapy based on the results from the DESTINY-Breast04 trial.

Enhertu (5.4 mg/kg) is approved in more than 45 countries/regions worldwide for the treatment of adult patients with unresectable or metastatic HR-positive, HER2-low (IHC 1+ or IHC 2+/ ISH-) or HER2-ultralow (IHC 0 with membrane staining) breast cancer, as determined by a locally or regionally approved test, that have progressed on one or more endocrine therapies in the metastatic setting based on the results from the DESTINY-Breast06 trial.

Enhertu (5.4 mg/kg) is approved in more than 60 countries/regions worldwide for the treatment of adult patients with unresectable or metastatic non-small cell lung cancer (NSCLC) whose tumours have activating HER2 (ERBB2) mutations, as detected by a locally or regionally approved test, and who have received a prior systemic therapy based on the results from the DESTINY-Lung02 and/or DESTINY-Lung05 trials. Continued approval in China and the U.S. for this indication may be contingent upon verification and description of clinical benefit in a confirmatory trial.

Enhertu (6.4 mg/kg) is approved in more than 70 countries/regions worldwide for the treatment of adult patients with locally advanced or metastatic HER2-positive (IHC 3+ or IHC 2+/ISH+) gastric or gastroesophageal junction (GEJ) adenocarcinoma who have received a prior trastuzumab-based regimen based on the results from the DESTINY-Gastric01, DESTINY-Gastric02 and/or DESTINY-Gastric06 trials. Continued approval in China for this indication may be contingent upon verification and description of clinical benefit in a confirmatory trial.

Enhertu (5.4 mg/kg) is approved in more than 10 countries/regions worldwide for the treatment of adult patients with unresectable or metastatic HER2-positive (IHC 3+) solid tumours who have received prior systemic treatment and have no satisfactory alternative treatment options based on efficacy results from the DESTINY-PanTumor02, DESTINY-Lung01 and DESTINY-CRC02 trials. Continued approval for this indication may be contingent upon verification and description of clinical benefit in a confirmatory trial.

Enhertu development programme
A comprehensive global clinical development programme is underway evaluating the efficacy and safety of Enhertu as a monotherapy or in combination or sequentially with other cancer medicines across multiple HER2-targetable cancers.

Daiichi Sankyo collaboration
AstraZeneca and Daiichi Sankyo entered into a global collaboration to jointly develop and commercialise Enhertu in March 2019 and Datroway (datopotamab deruxtecan) in July 2020, except in Japan where Daiichi Sankyo maintains exclusive rights for each ADC. Daiichi Sankyo is responsible for the manufacturing and supply of Enhertu and Datroway.

AstraZeneca in breast cancer
Driven by a growing understanding of breast cancer biology, AstraZeneca is challenging, and redefining, the current clinical paradigm for how breast cancer is classified and treated to deliver even more effective treatments to patients in need – with the bold ambition to one day eliminate breast cancer as a cause of death.

AstraZeneca has a comprehensive portfolio of approved and promising compounds in development that leverage different mechanisms of action to address the biologically diverse breast cancer tumour environment.

With Enhertu, AstraZeneca and Daiichi Sankyo are aiming to improve outcomes in previously treated HER2-positive, HER2-low and HER2-ultralow metastatic breast cancer, and are exploring its potential in earlier lines of treatment and in new breast cancer settings.

In HR-positive breast cancer, AstraZeneca continues to improve outcomes with foundational medicines Faslodex (fulvestrant) and Zoladex (goserelin) and aims to reshape the HR-positive space with first-in-class AKT inhibitor, Truqap (capivasertib), the TROP2-directed ADC, Datroway (datopotamab deruxtecan), and next-generation oral SERD and potential new medicine camizestrant.

PARP inhibitor Lynparza (olaparib) is a targeted treatment option that has been studied in early and metastatic breast cancer patients with an inherited BRCA mutation. AstraZeneca with MSD (Merck & Co., Inc. in the US and Canada) continue to research Lynparza in these settings. AstraZeneca is also exploring the potential of saruparib, a potent and selective inhibitor of PARP1, in combination with camizestrant in BRCA-mutated, HR-positive, HER2-negative advanced breast cancer.

To bring much-needed treatment options to patients with triple-negative breast cancer, an aggressive form of breast cancer, AstraZeneca is collaborating with Daiichi Sankyo to evaluate the potential of Datroway alone and in combination with immunotherapy Imfinzi (durvalumab).

(Press release, AstraZeneca, OCT 18, 2025, View Source [SID1234656784])

Delcath Systems Announces Preliminary Third Quarter 2025 Financial Results

On October 18, 2025 Delcath Systems, Inc. (NASDAQ: DCTH), an interventional oncology company focused on the treatment of primary and metastatic liver cancers, reported preliminary revenue and financial results for the quarter ended September 30, 2025, and updated 2025 full-year revenue guidance.

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Preliminary Third Quarter Financial Results (unaudited)

Total CHEMOSAT and HEPZATO KIT revenue of approximately $20.5 million
HEPZATO KIT revenue of $19.2 million
CHEMOSAT revenue of $1.3 million
Gross margins expected to be 87%
Net income of $0.8 million

Positive adjusted EBITDA of $5.3 million
Positive operating cashflow of approximately $4.8 million

As of September 30, 2025, the Company had approximately $88.9 million of cash, cash equivalents and short-term investments and no debt.

2025 Full Year Financial Guidance

Total CHEMOSAT and HEPZATO KIT revenue of $83 million to $85 million, reflecting an approximate 150% increase in treatment volume over 2024
Quarterly gross margins between 85% to 87%
Positive adjusted EBITDA and operating cashflow in each quarter of 2025
"Although our third quarter revenue was modestly lower than the second quarter, this decline was primarily due to the NDRA discounts and unexpected summer seasonality which impacted the scheduling of new patient starts," said Gerard Michel, Chief Executive Officer of Delcath Systems. "We are confident that we will achieve strong growth in 2026 and beyond. This expectation is based on our ongoing expansion of active treatment centers and the positive influence of the CHOPIN trial results, which have demonstrated impressive efficacy and offer practical advantages for initiating patients on systemic therapy, while preparing for PHP therapy."

Conference Call Information

Delcath Systems, Inc. will host a conference call and webcast on October 20, 2025, at 8:45 a.m. Eastern Time to discuss the Phase 2 CHOPIN Trial results and provide a brief overview of the financial results announced in this release. Joining Delcath management on the call with pre-recorded remarks will be Dr. Vincent T. Ma, Assistant Professor and Medical Oncologist at the University of Wisconsin Department of Medicine, a current user of HEPZATO KIT for the treatment of metastatic uveal melanoma patients, an expert in treating cutaneous melanoma, and a co-author on the seminal Nature Medicine paper exploring liver immune tolerance mechanisms in cancer.

To participate in this event, dial in approximately 5 to 10 minutes before the beginning of the call.

Event Date: Monday, October 20
Time: 8:45 AM Eastern Time

Participant Numbers:
Toll Free: 1-877-407-3982
International: 1-201-493-6780
Webcast: View Source;tp_key=6f3953dd75

A replay of the webinar will be available shortly after the conclusion of the call and will be archived on the company’s website View Source

(Press release, Delcath Systems, OCT 18, 2025, View Source [SID1234656767])

KEYTRUDA® (pembrolizumab) Plus Padcev® (enfortumab vedotin-ejfv) Reduced Risk of Event-Free Survival Events by 60% and Risk of Death by 50% for Certain Patients with Muscle-Invasive Bladder Cancer When Given Before and After Surgery

On October 18, 2025 Merck (NYSE: MRK), known as MSD outside of the United States and Canada, reported landmark results demonstrating KEYTRUDA (pembrolizumab) plus Padcev (enfortumab vedotin-ejfv) reduced the risk of event-free survival (EFS) events by 60% and reduced the risk of death by 50% when given before and after surgery (radical cystectomy) versus surgery alone, the current standard of care, in patients with muscle-invasive bladder cancer (MIBC) who are not eligible for or declined cisplatin-based chemotherapy. These late-breaking data will be presented for the first time today during a Presidential Symposium session at the European Society for Medical Oncology (ESMO) (Free ESMO Whitepaper) Congress 2025 (Presentation #LBA2) and were selected for an official Press Briefing.

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After a median follow-up of 25.6 months, KEYTRUDA plus Padcev, as perioperative treatment, demonstrated a statistically significant and clinically meaningful improvement in EFS, the trial’s primary endpoint, reducing the risk of EFS events by 60% (HR=0.40 [95% CI, 0.28-0.57]; p<0.0001) versus surgery alone in patients with MIBC who are not eligible for or declined cisplatin-based chemotherapy. Median EFS was not reached [NR] (95% CI, 37.3-NR) for the KEYTRUDA plus Padcev regimen versus 15.7 months (95% CI, 10.3-20.5) for surgery alone.

"For decades, patients with muscle-invasive bladder cancer who are ineligible for cisplatin treatment have faced limited treatment options, often relying on surgery alone. The groundbreaking benefits seen in the KEYNOTE-905/EV-303 trial, at this interim analysis, position the pembrolizumab and enfortumab vedotin combination to change the way we approach the treatment of patients with this disease," said Dr. Christof Vulsteke, head of the Integrated Cancer Center Ghent (IKG) and Clinical Trial Unit Oncology Ghent, and KEYNOTE-905/EV-303 principal investigator.

KEYTRUDA plus Padcev also demonstrated a statistically significant and clinically meaningful improvement in key secondary endpoints of overall survival (OS) and pathologic complete response (pCR) rate. KEYTRUDA plus Padcev reduced the risk of death by 50% (HR=0.50 [95% CI, 0.33-0.74]; p=0.0002) versus surgery. For patients who received the KEYTRUDA plus Padcev regimen, median OS was NR (95% CI, NR-NR) versus 41.7 months (95% CI, 31.8-NR) for patients receiving surgery alone. The pCR rate increased from 8.6% in patients treated with surgery alone (n=15/174) to 57.1% in patients treated with perioperative KEYTRUDA plus Padcev (n=97/170), an estimated increase of 48.3 percentage points (95% CI, 39.5-56.5; p<0.000001).

"KEYTRUDA plus Padcev has once again demonstrated a significant improvement in survival for patients with bladder cancer, this time in an earlier stage of the disease as the KEYNOTE-905 study results show," said Dr. Marjorie Green, senior vice president and head of oncology, global clinical development, Merck Research Laboratories. "These data – from the first-ever positive Phase 3 trial exclusively in this cisplatin-ineligible patient population – represent a potentially practice-changing advancement to help address a critical unmet need for these patients."

The trial, evaluating Merck’s KEYTRUDA, an anti-PD-1 therapy, plus Padcev, an antibody-drug conjugate (ADC), was conducted in collaboration with Pfizer (previously Seagen) and Astellas. The companies plan to share these results with regulatory authorities worldwide. KEYTRUDA plus Padcev is currently approved for the treatment of adult patients with locally advanced or metastatic urothelial cancer (la/mUC) in the U.S., the European Union (EU), Japan and several other countries around the world based on results from the Phase 3 KEYNOTE-A39 trial, also known as EV-302. KEYTRUDA as a monotherapy is also approved in the U.S., EU, Japan and other countries for the treatment of certain patients with la/mUC or a type of non-muscle-invasive bladder cancer (NMIBC).

Four additional Phase 3 studies are currently evaluating KEYTRUDA across all stages of bladder cancer, including non-muscle-invasive, muscle-invasive and metastatic disease. Three of these studies are in MIBC including KEYNOTE-B15 (NCT04700124), which is also known as EV-304 and is being conducted in collaboration with Pfizer and Astellas, KEYNOTE-866 (NCT03924856) and KEYNOTE-992 (NCT04241185). KEYTRUDA is also being evaluated in combination with Bacillus Calmette-Guerin (BCG) in patients with NMIBC in the Phase 3 KEYNOTE-676 (NCT03711032) trial.

KEYNOTE-905 is one of five Phase 3 studies of a KEYTRUDA-based regimen in an earlier stage of cancer to demonstrate an OS benefit, in addition to KEYNOTE-A18 in combination with concurrent chemoradiotherapy (CRT) for newly diagnosed patients with high-risk (stage IB2-IIB with lymph node-positive disease and stage III-IVA with and without lymph node-positive disease) locally advanced cervical cancer, KEYNOTE-522 in newly diagnosed, high-risk early-stage triple-negative breast cancer, KEYNOTE-671 in resectable stage II, IIIA or IIIB non-small cell lung cancer (in both studies, as treatment with chemotherapy before surgery and then as a single agent after surgery, compared to pre-operative chemotherapy), as well as KEYNOTE-564 in renal cell carcinoma for patients at intermediate-high or high risk of recurrence following nephrectomy, or following nephrectomy and resection of metastatic lesions (compared to placebo). It is also the 13th positive pivotal trial for a KEYTRUDA-based regimen in earlier-stage cancers.

Study design and additional data from KEYNOTE-905
KEYNOTE-905, also known as EV-303, is an open-label, randomized, multi-arm, controlled Phase 3 trial (NCT03924895) evaluating perioperative KEYTRUDA, with or without Padcev, versus surgery alone in patients with MIBC who are either not eligible for or declined cisplatin-based chemotherapy. The trial enrolled 595 patients who were randomized to receive either:

Arm A: Three cycles of neoadjuvant KEYTRUDA, followed by surgery to remove the bladder (radical cystectomy), followed by 14 cycles of adjuvant KEYTRUDA;
Arm B: Surgery alone;
Arm C: Three cycles of neoadjuvant KEYTRUDA plus enfortumab vedotin, followed by surgery to remove the bladder (radical cystectomy), followed adjuvantly by six cycles of KEYTRUDA plus enfortumab vedotin and then eight cycles of KEYTRUDA alone.
The primary objective of this trial is to compare EFS between arm C and arm B, defined as the time from randomization to the first occurrence of any of the following events: progression of disease that precludes radical cystectomy (RC) surgery or failure to undergo RC surgery in participants with residual disease, gross residual disease left behind at the time of surgery, local or distant recurrence as assessed by imaging and/or biopsy or death due to any cause. The key secondary objectives are to compare OS and the difference in pCR rate between arm C and arm B, as well as EFS, OS and the difference in pCR rate between arm A and arm B. The study remains ongoing to test hypotheses between arm A and arm B.

The safety profile of KEYTRUDA plus Padcev in this study was consistent with the known safety profiles of each agent. Treatment-emergent adverse events (TEAEs) occurred in 100% of patients receiving KEYTRUDA plus Padcev (n=167) and 64.8% of patients receiving surgery alone (n=103); Grade ≥3 TEAEs occurred in 71.3% (n=119) versus 45.9% (n=73), respectively. The most frequent grade ≥3 TEAE of special interest (based on distinct prespecified lists for each drug) was severe skin reactions for KEYTRUDA and skin reactions for Padcev.

About bladder cancer
Bladder cancer is the ninth most common cancer worldwide, diagnosed in more than 614,000 patients each year globally. Muscle-invasive bladder cancer represents approximately 30% of all bladder cancer cases. The standard of care for patients with MIBC has been neoadjuvant cisplatin-based chemotherapy followed by surgery, which is shown to prolong survival. However, up to half of patients with MIBC are not eligible to receive cisplatin and face limited treatment options, typically undergoing surgery alone.

About Merck’s early-stage cancer clinical program
Finding cancer at an earlier stage may give patients a greater chance of long-term survival. Many cancers are considered most treatable and potentially curable in their earliest stage of disease. Building on the strong understanding of the role of KEYTRUDA in later-stage cancers, Merck is evaluating our portfolio of medicines and pipeline candidates in earlier disease states, with more than 30 ongoing registrational studies across multiple types of cancer.

About KEYTRUDA (pembrolizumab) injection, 100 mg
KEYTRUDA is an anti-programmed death receptor-1 (PD-1) therapy that works by increasing the ability of the body’s immune system to help detect and fight tumor cells. KEYTRUDA is a humanized monoclonal antibody that blocks the interaction between PD-1 and its ligands, PD-L1 and PD-L2, thereby activating T lymphocytes which may affect both tumor cells and healthy cells.

Merck has the industry’s largest immuno-oncology clinical research program. There are currently more than 1,600 trials studying KEYTRUDA across a wide variety of cancers and treatment settings. The KEYTRUDA clinical program seeks to understand the role of KEYTRUDA across cancers and the factors that may predict a patient’s likelihood of benefitting from treatment with KEYTRUDA, including exploring several different biomarkers.

Selected KEYTRUDA (pembrolizumab) Indications in the U.S.
Urothelial Cancer
KEYTRUDA, in combination with enfortumab vedotin, is indicated for the treatment of adult patients with locally advanced or metastatic urothelial cancer.

KEYTRUDA, as a single agent, is indicated for the treatment of patients with locally advanced or metastatic urothelial carcinoma:

who are not eligible for any platinum-containing chemotherapy, or
who have disease progression during or following platinum-containing chemotherapy or within 12 months of neoadjuvant or adjuvant treatment with platinum-containing chemotherapy.
KEYTRUDA, as a single agent, is indicated for the treatment of patients with Bacillus Calmette-Guerin (BCG)-unresponsive, high-risk, non-muscle invasive bladder cancer (NMIBC) with carcinoma in situ (CIS) with or without papillary tumors who are ineligible for or have elected not to undergo cystectomy.

See additional selected KEYTRUDA indications in the U.S. after the Selected Important Safety Information.

Selected Important Safety Information for KEYTRUDA
Severe and Fatal Immune-Mediated Adverse Reactions
KEYTRUDA is a monoclonal antibody that belongs to a class of drugs that bind to either the programmed death receptor-1 (PD-1) or the programmed death ligand 1 (PD-L1), blocking the PD-1/PD-L1 pathway, thereby removing inhibition of the immune response, potentially breaking peripheral tolerance and inducing immune-mediated adverse reactions. Immune-mediated adverse reactions, which may be severe or fatal, can occur in any organ system or tissue, can affect more than one body system simultaneously, and can occur at any time after starting treatment or after discontinuation of treatment. Important immune-mediated adverse reactions listed here may not include all possible severe and fatal immune-mediated adverse reactions.

Monitor patients closely for symptoms and signs that may be clinical manifestations of underlying immune-mediated adverse reactions. Early identification and management are essential to ensure safe use of anti–PD-1/PD-L1 treatments. Evaluate liver enzymes, creatinine, and thyroid function at baseline and periodically during treatment. For patients with TNBC treated with KEYTRUDA in the neoadjuvant setting, monitor blood cortisol at baseline, prior to surgery, and as clinically indicated. In cases of suspected immune-mediated adverse reactions, initiate appropriate workup to exclude alternative etiologies, including infection. Institute medical management promptly, including specialty consultation as appropriate.

Withhold or permanently discontinue KEYTRUDA depending on severity of the immune-mediated adverse reaction. In general, if KEYTRUDA requires interruption or discontinuation, administer systemic corticosteroid therapy (1 to 2 mg/kg/day prednisone or equivalent) until improvement to Grade 1 or less. Upon improvement to Grade 1 or less, initiate corticosteroid taper and continue to taper over at least 1 month. Consider administration of other systemic immunosuppressants in patients whose adverse reactions are not controlled with corticosteroid therapy.

Immune-Mediated Pneumonitis
KEYTRUDA can cause immune-mediated pneumonitis. The incidence is higher in patients who have received prior thoracic radiation. Immune-mediated pneumonitis occurred in 3.4% (94/2799) of patients receiving KEYTRUDA, including fatal (0.1%), Grade 4 (0.3%), Grade 3 (0.9%), and Grade 2 (1.3%) reactions. Systemic corticosteroids were required in 67% (63/94) of patients. Pneumonitis led to permanent discontinuation of KEYTRUDA in 1.3% (36) and withholding in 0.9% (26) of patients. All patients who were withheld reinitiated KEYTRUDA after symptom improvement; of these, 23% had recurrence. Pneumonitis resolved in 59% of the 94 patients.

Pneumonitis occurred in 8% (31/389) of adult patients with cHL receiving KEYTRUDA as a single agent, including Grades 3-4 in 2.3% of patients. Patients received high-dose corticosteroids for a median duration of 10 days (range: 2 days to 53 months). Pneumonitis rates were similar in patients with and without prior thoracic radiation. Pneumonitis led to discontinuation of KEYTRUDA in 5.4% (21) of patients. Of the patients who developed pneumonitis, 42% interrupted KEYTRUDA, 68% discontinued KEYTRUDA, and 77% had resolution.

Pneumonitis occurred in 7% (41/580) of adult patients with resected NSCLC who received KEYTRUDA as a single agent for adjuvant treatment of NSCLC, including fatal (0.2%), Grade 4 (0.3%), and Grade 3 (1%) adverse reactions. Patients received high-dose corticosteroids for a median duration of 10 days (range: 1 day to 2.3 months). Pneumonitis led to discontinuation of KEYTRUDA in 26 (4.5%) of patients. Of the patients who developed pneumonitis, 54% interrupted KEYTRUDA, 63% discontinued KEYTRUDA, and 71% had resolution.

Immune-Mediated Colitis
KEYTRUDA can cause immune-mediated colitis, which may present with diarrhea. Cytomegalovirus infection/reactivation has been reported in patients with corticosteroid-refractory immune-mediated colitis. In cases of corticosteroid-refractory colitis, consider repeating infectious workup to exclude alternative etiologies. Immune-mediated colitis occurred in 1.7% (48/2799) of patients receiving KEYTRUDA, including Grade 4 (<0.1%), Grade 3 (1.1%), and Grade 2 (0.4%) reactions. Systemic corticosteroids were required in 69% (33/48); additional immunosuppressant therapy was required in 4.2% of patients. Colitis led to permanent discontinuation of KEYTRUDA in 0.5% (15) and withholding in 0.5% (13) of patients. All patients who were withheld reinitiated KEYTRUDA after symptom improvement; of these, 23% had recurrence. Colitis resolved in 85% of the 48 patients.

Hepatotoxicity and Immune-Mediated Hepatitis
KEYTRUDA as a Single Agent
KEYTRUDA can cause immune-mediated hepatitis. Immune-mediated hepatitis occurred in 0.7% (19/2799) of patients receiving KEYTRUDA, including Grade 4 (<0.1%), Grade 3 (0.4%), and Grade 2 (0.1%) reactions. Systemic corticosteroids were required in 68% (13/19) of patients; additional immunosuppressant therapy was required in 11% of patients. Hepatitis led to permanent discontinuation of KEYTRUDA in 0.2% (6) and withholding in 0.3% (9) of patients. All patients who were withheld reinitiated KEYTRUDA after symptom improvement; of these, none had recurrence. Hepatitis resolved in 79% of the 19 patients.

KEYTRUDA With Axitinib
KEYTRUDA in combination with axitinib can cause hepatic toxicity. Monitor liver enzymes before initiation of and periodically throughout treatment. Consider monitoring more frequently as compared to when the drugs are administered as single agents. For elevated liver enzymes, interrupt KEYTRUDA and axitinib, and consider administering corticosteroids as needed. With the combination of KEYTRUDA and axitinib, Grades 3 and 4 increased alanine aminotransferase (ALT) (20%) and increased aspartate aminotransferase (AST) (13%) were seen at a higher frequency compared to KEYTRUDA alone. Fifty-nine percent of the patients with increased ALT received systemic corticosteroids. In patients with ALT ≥3 times upper limit of normal (ULN) (Grades 2-4, n=116), ALT resolved to Grades 0-1 in 94%. Among the 92 patients who were rechallenged with either KEYTRUDA (n=3) or axitinib (n=34) administered as a single agent or with both (n=55), recurrence of ALT ≥3 times ULN was observed in 1 patient receiving KEYTRUDA, 16 patients receiving axitinib, and 24 patients receiving both. All patients with a recurrence of ALT ≥3 ULN subsequently recovered from the event.

Immune-Mediated Endocrinopathies
Adrenal Insufficiency
KEYTRUDA can cause primary or secondary adrenal insufficiency. For Grade 2 or higher, initiate symptomatic treatment, including hormone replacement as clinically indicated. Withhold KEYTRUDA depending on severity. Adrenal insufficiency occurred in 0.8% (22/2799) of patients receiving KEYTRUDA, including Grade 4 (<0.1%), Grade 3 (0.3%), and Grade 2 (0.3%) reactions. Systemic corticosteroids were required in 77% (17/22) of patients; of these, the majority remained on systemic corticosteroids. Adrenal insufficiency led to permanent discontinuation of KEYTRUDA in <0.1% (1) and withholding in 0.3% (8) of patients. All patients who were withheld reinitiated KEYTRUDA after symptom improvement.

Hypophysitis
KEYTRUDA can cause immune-mediated hypophysitis. Hypophysitis can present with acute symptoms associated with mass effect such as headache, photophobia, or visual field defects. Hypophysitis can cause hypopituitarism. Initiate hormone replacement as indicated. Withhold or permanently discontinue KEYTRUDA depending on severity. Hypophysitis occurred in 0.6% (17/2799) of patients receiving KEYTRUDA, including Grade 4 (<0.1%), Grade 3 (0.3%), and Grade 2 (0.2%) reactions. Systemic corticosteroids were required in 94% (16/17) of patients; of these, the majority remained on systemic corticosteroids. Hypophysitis led to permanent discontinuation of KEYTRUDA in 0.1% (4) and withholding in 0.3% (7) of patients. All patients who were withheld reinitiated KEYTRUDA after symptom improvement.

Thyroid Disorders
KEYTRUDA can cause immune-mediated thyroid disorders. Thyroiditis can present with or without endocrinopathy. Hypothyroidism can follow hyperthyroidism. Initiate hormone replacement for hypothyroidism or institute medical management of hyperthyroidism as clinically indicated. Withhold or permanently discontinue KEYTRUDA depending on severity. Thyroiditis occurred in 0.6% (16/2799) of patients receiving KEYTRUDA, including Grade 2 (0.3%). None discontinued, but KEYTRUDA was withheld in <0.1% (1) of patients.

Hyperthyroidism occurred in 3.4% (96/2799) of patients receiving KEYTRUDA, including Grade 3 (0.1%) and Grade 2 (0.8%). It led to permanent discontinuation of KEYTRUDA in <0.1% (2) and withholding in 0.3% (7) of patients. All patients who were withheld reinitiated KEYTRUDA after symptom improvement. Hypothyroidism occurred in 8% (237/2799) of patients receiving KEYTRUDA, including Grade 3 (0.1%) and Grade 2 (6.2%). It led to permanent discontinuation of KEYTRUDA in <0.1% (1) and withholding in 0.5% (14) of patients. All patients who were withheld reinitiated KEYTRUDA after symptom improvement. The majority of patients with hypothyroidism required long-term thyroid hormone replacement. The incidence of new or worsening hypothyroidism was higher in 1185 patients with HNSCC, occurring in 16% of patients receiving KEYTRUDA as a single agent or in combination with platinum and FU, including Grade 3 (0.3%) hypothyroidism. The incidence of new or worsening hypothyroidism was higher in 389 adult patients with cHL (17%) receiving KEYTRUDA as a single agent, including Grade 1 (6.2%) and Grade 2 (10.8%) hypothyroidism. The incidence of new or worsening hyperthyroidism was higher in 580 patients with resected NSCLC, occurring in 11% of patients receiving KEYTRUDA as a single agent as adjuvant treatment, including Grade 3 (0.2%) hyperthyroidism. The incidence of new or worsening hypothyroidism was higher in 580 patients with resected NSCLC, occurring in 22% of patients receiving KEYTRUDA as a single agent as adjuvant treatment (KEYNOTE-091), including Grade 3 (0.3%) hypothyroidism.

Type 1 Diabetes Mellitus (DM), Which Can Present With Diabetic Ketoacidosis
Monitor patients for hyperglycemia or other signs and symptoms of diabetes. Initiate treatment with insulin as clinically indicated. Withhold KEYTRUDA depending on severity. Type 1 DM occurred in 0.2% (6/2799) of patients receiving KEYTRUDA. It led to permanent discontinuation in <0.1% (1) and withholding of KEYTRUDA in <0.1% (1) of patients. All patients who were withheld reinitiated KEYTRUDA after symptom improvement.

Immune-Mediated Nephritis With Renal Dysfunction
KEYTRUDA can cause immune-mediated nephritis. Immune-mediated nephritis occurred in 0.3% (9/2799) of patients receiving KEYTRUDA, including Grade 4 (<0.1%), Grade 3 (0.1%), and Grade 2 (0.1%) reactions. Systemic corticosteroids were required in 89% (8/9) of patients. Nephritis led to permanent discontinuation of KEYTRUDA in 0.1% (3) and withholding in 0.1% (3) of patients. All patients who were withheld reinitiated KEYTRUDA after symptom improvement; of these, none had recurrence. Nephritis resolved in 56% of the 9 patients.

Immune-Mediated Dermatologic Adverse Reactions
KEYTRUDA can cause immune-mediated rash or dermatitis. Exfoliative dermatitis, including Stevens-Johnson syndrome, drug rash with eosinophilia and systemic symptoms, and toxic epidermal necrolysis, has occurred with anti–PD-1/PD-L1 treatments. Topical emollients and/or topical corticosteroids may be adequate to treat mild to moderate nonexfoliative rashes. Withhold or permanently discontinue KEYTRUDA depending on severity. Immune-mediated dermatologic adverse reactions occurred in 1.4% (38/2799) of patients receiving KEYTRUDA, including Grade 3 (1%) and Grade 2 (0.1%) reactions. Systemic corticosteroids were required in 40% (15/38) of patients. These reactions led to permanent discontinuation in 0.1% (2) and withholding of KEYTRUDA in 0.6% (16) of patients. All patients who were withheld reinitiated KEYTRUDA after symptom improvement; of these, 6% had recurrence. The reactions resolved in 79% of the 38 patients.

Other Immune-Mediated Adverse Reactions
The following clinically significant immune-mediated adverse reactions occurred at an incidence of <1% (unless otherwise noted) in patients who received KEYTRUDA or were reported with the use of other anti–PD-1/PD-L1 treatments. Severe or fatal cases have been reported for some of these adverse reactions. Cardiac/Vascular: Myocarditis, pericarditis, vasculitis; Nervous System: Meningitis, encephalitis, myelitis and demyelination, myasthenic syndrome/myasthenia gravis (including exacerbation), Guillain-Barré syndrome, nerve paresis, autoimmune neuropathy; Ocular: Uveitis, iritis and other ocular inflammatory toxicities can occur. Some cases can be associated with retinal detachment. Various grades of visual impairment, including blindness, can occur. If uveitis occurs in combination with other immune-mediated adverse reactions, consider a Vogt-Koyanagi-Harada-like syndrome, as this may require treatment with systemic steroids to reduce the risk of permanent vision loss; Gastrointestinal: Pancreatitis, to include increases in serum amylase and lipase levels, gastritis, duodenitis; Musculoskeletal and Connective Tissue: Myositis/polymyositis, rhabdomyolysis (and associated sequelae, including renal failure), arthritis (1.5%), polymyalgia rheumatica; Endocrine: Hypoparathyroidism; Hematologic/Immune: Hemolytic anemia, aplastic anemia, hemophagocytic lymphohistiocytosis, systemic inflammatory response syndrome, histiocytic necrotizing lymphadenitis (Kikuchi lymphadenitis), sarcoidosis, immune thrombocytopenic purpura, solid organ transplant rejection, other transplant (including corneal graft) rejection.

Infusion-Related Reactions
KEYTRUDA can cause severe or life-threatening infusion-related reactions, including hypersensitivity and anaphylaxis, which have been reported in 0.2% of 2799 patients receiving KEYTRUDA. Monitor for signs and symptoms of infusion-related reactions. Interrupt or slow the rate of infusion for Grade 1 or Grade 2 reactions. For Grade 3 or Grade 4 reactions, stop infusion and permanently discontinue KEYTRUDA.

Complications of Allogeneic Hematopoietic Stem Cell Transplantation (HSCT)
Fatal and other serious complications can occur in patients who receive allogeneic HSCT before or after anti–PD-1/PD-L1 treatments. Transplant-related complications include hyperacute graft-versus-host disease (GVHD), acute and chronic GVHD, hepatic veno-occlusive disease after reduced intensity conditioning, and steroid-requiring febrile syndrome (without an identified infectious cause). These complications may occur despite intervening therapy between anti–PD-1/PD-L1 treatments and allogeneic HSCT. Follow patients closely for evidence of these complications and intervene promptly. Consider the benefit vs risks of using anti–PD-1/PD-L1 treatments prior to or after an allogeneic HSCT.

Increased Mortality in Patients With Multiple Myeloma
In trials in patients with multiple myeloma, the addition of KEYTRUDA to a thalidomide analogue plus dexamethasone resulted in increased mortality. Treatment of these patients with an anti–PD-1/PD-L1 treatment in this combination is not recommended outside of controlled trials.

Embryofetal Toxicity
Based on its mechanism of action, KEYTRUDA can cause fetal harm when administered to a pregnant woman. Advise women of this potential risk. In females of reproductive potential, verify pregnancy status prior to initiating KEYTRUDA and advise them to use effective contraception during treatment and for 4 months after the last dose.

Adverse Reactions
In KEYNOTE-006, KEYTRUDA was discontinued due to adverse reactions in 9% of 555 patients with advanced melanoma; adverse reactions leading to permanent discontinuation in more than one patient were colitis (1.4%), autoimmune hepatitis (0.7%), allergic reaction (0.4%), polyneuropathy (0.4%), and cardiac failure (0.4%). The most common adverse reactions (≥20%) with KEYTRUDA were fatigue (28%), diarrhea (26%), rash (24%), and nausea (21%).

In KEYNOTE-054, when KEYTRUDA was administered as a single agent to patients with stage III melanoma, KEYTRUDA was permanently discontinued due to adverse reactions in 14% of 509 patients; the most common (≥1%) were pneumonitis (1.4%), colitis (1.2%), and diarrhea (1%). Serious adverse reactions occurred in 25% of patients receiving KEYTRUDA. The most common adverse reaction (≥20%) with KEYTRUDA was diarrhea (28%). In KEYNOTE-716, when KEYTRUDA was administered as a single agent to patients with stage IIB or IIC melanoma, adverse reactions occurring in patients with stage IIB or IIC melanoma were similar to those occurring in 1011 patients with stage III melanoma from KEYNOTE-054.

In KEYNOTE-189, when KEYTRUDA was administered with pemetrexed and platinum chemotherapy in metastatic nonsquamous NSCLC, KEYTRUDA was discontinued due to adverse reactions in 20% of 405 patients. The most common adverse reactions resulting in permanent discontinuation of KEYTRUDA were pneumonitis (3%) and acute kidney injury (2%). The most common adverse reactions (≥20%) with KEYTRUDA were nausea (56%), fatigue (56%), constipation (35%), diarrhea (31%), decreased appetite (28%), rash (25%), vomiting (24%), cough (21%), dyspnea (21%), and pyrexia (20%).

In KEYNOTE-407, when KEYTRUDA was administered with carboplatin and either paclitaxel or paclitaxel protein-bound in metastatic squamous NSCLC, KEYTRUDA was discontinued due to adverse reactions in 15% of 101 patients. The most frequent serious adverse reactions reported in at least 2% of patients were febrile neutropenia, pneumonia, and urinary tract infection. Adverse reactions observed in KEYNOTE-407 were similar to those observed in KEYNOTE-189 with the exception that increased incidences of alopecia (47% vs 36%) and peripheral neuropathy (31% vs 25%) were observed in the KEYTRUDA and chemotherapy arm compared to the placebo and chemotherapy arm in KEYNOTE-407.

In KEYNOTE-042, KEYTRUDA was discontinued due to adverse reactions in 19% of 636 patients with advanced NSCLC; the most common were pneumonitis (3%), death due to unknown cause (1.6%), and pneumonia (1.4%). The most frequent serious adverse reactions reported in at least 2% of patients were pneumonia (7%), pneumonitis (3.9%), pulmonary embolism (2.4%), and pleural effusion (2.2%). The most common adverse reaction (≥20%) was fatigue (25%).

In KEYNOTE-010, KEYTRUDA monotherapy was discontinued due to adverse reactions in 8% of 682 patients with metastatic NSCLC; the most common was pneumonitis (1.8%). The most common adverse reactions (≥20%) were decreased appetite (25%), fatigue (25%), dyspnea (23%), and nausea (20%).

In KEYNOTE-671, adverse reactions occurring in patients with resectable NSCLC receiving KEYTRUDA in combination with platinum-containing chemotherapy, given as neoadjuvant treatment and continued as single-agent adjuvant treatment, were generally similar to those occurring in patients in other clinical trials across tumor types receiving KEYTRUDA in combination with chemotherapy.

The most common adverse reactions (reported in ≥20%) in patients receiving KEYTRUDA in combination with chemotherapy or chemoradiotherapy were fatigue/asthenia, nausea, constipation, diarrhea, decreased appetite, rash, vomiting, cough, dyspnea, pyrexia, alopecia, peripheral neuropathy, mucosal inflammation, stomatitis, headache, weight loss, abdominal pain, arthralgia, myalgia, insomnia, palmar-plantar erythrodysesthesia, urinary tract infection, hypothyroidism, radiation skin injury, dysphagia, dry mouth, and musculoskeletal pain.

In the neoadjuvant phase of KEYNOTE-671, when KEYTRUDA was administered in combination with platinum-containing chemotherapy as neoadjuvant treatment, serious adverse reactions occurred in 34% of 396 patients. The most frequent (≥2%) serious adverse reactions were pneumonia (4.8%), venous thromboembolism (3.3%), and anemia (2%). Fatal adverse reactions occurred in 1.3% of patients, including death due to unknown cause (0.8%), sepsis (0.3%), and immune-mediated lung disease (0.3%). Permanent discontinuation of any study drug due to an adverse reaction occurred in 18% of patients who received KEYTRUDA in combination with platinum-containing chemotherapy; the most frequent adverse reactions (≥1%) that led to permanent discontinuation of any study drug were acute kidney injury (1.8%), interstitial lung disease (1.8%), anemia (1.5%), neutropenia (1.5%), and pneumonia (1.3%).

Of the KEYTRUDA-treated patients who received neoadjuvant treatment, 6% of 396 patients did not receive surgery due to adverse reactions. The most frequent (≥1%) adverse reaction that led to cancellation of surgery in the KEYTRUDA arm was interstitial lung disease (1%).

In the adjuvant phase of KEYNOTE-671, when KEYTRUDA was administered as a single agent as adjuvant treatment, serious adverse reactions occurred in 14% of 290 patients. The most frequent serious adverse reaction was pneumonia (3.4%). One fatal adverse reaction of pulmonary hemorrhage occurred. Permanent discontinuation of KEYTRUDA due to an adverse reaction occurred in 12% of patients who received KEYTRUDA as a single agent, given as adjuvant treatment; the most frequent adverse reactions (≥1%) that led to permanent discontinuation of KEYTRUDA were diarrhea (1.7%), interstitial lung disease (1.4%), increased aspartate aminotransferase (1%), and musculoskeletal pain (1%).

Adverse reactions observed in KEYNOTE-091 were generally similar to those occurring in other patients with NSCLC receiving KEYTRUDA as a single agent, with the exception of hypothyroidism (22%), hyperthyroidism (11%), and pneumonitis (7%). Two fatal adverse reactions of myocarditis occurred.

Adverse reactions observed in KEYNOTE-483 were generally similar to those occurring in other patients receiving KEYTRUDA in combination with pemetrexed and platinum chemotherapy.

In KEYNOTE-689, the most common adverse reactions (≥20%) in patients receiving KEYTRUDA were stomatitis (48%), radiation skin injury (40%), weight loss (36%), fatigue (33%), dysphagia (29%), constipation (27%), hypothyroidism (26%), nausea (24%), rash (22%), dry mouth (22%), diarrhea (22%), and musculoskeletal pain (22%).

In the neoadjuvant phase of KEYNOTE-689, of the 361 patients who received at least one dose of single agent KEYTRUDA, 11% experienced serious adverse reactions. Serious adverse reactions that occurred in more than one patient were pneumonia (1.4%), tumor hemorrhage (0.8%), dysphagia (0.6%), immune-mediated hepatitis (0.6%), cellulitis (0.6%), and dyspnea (0.6%). Fatal adverse reactions occurred in 1.1% of patients, including respiratory failure, clostridium infection, septic shock, and myocardial infarction (one patient each). Permanent discontinuation of KEYTRUDA due to an adverse reaction occurred in 2.8% of patients who received KEYTRUDA as neoadjuvant treatment. The most frequent adverse reaction which resulted in permanent discontinuation of neoadjuvant KEYTRUDA in more than one patient was arthralgia (0.6%).

Of the 361 patients who received KEYTRUDA as neoadjuvant treatment, 11% did not receive surgery. Surgical cancellation on the KEYTRUDA arm was due to disease progression in 4%, patient decision in 3%, adverse reactions in 1.4%, physician’s decision in 1.1%, unresectable tumor in 0.6%, loss of follow-up in 0.3%, and use of non-study anti-cancer therapy in 0.3%.

Of the 323 KEYTRUDA-treated patients who received surgery following the neoadjuvant phase, 1.2% experienced delay of surgery (defined as on-study surgery occurring ≥9 weeks after initiation of neoadjuvant KEYTRUDA) due to adverse reactions, and 2.8% did not receive adjuvant treatment due to adverse reactions.

In the adjuvant phase of KEYNOTE-689, of the 255 patients who received at least one dose of KEYTRUDA, 38% experienced serious adverse reactions. The most frequent serious adverse reactions reported in ≥1% of KEYTRUDA- treated patients were pneumonia (2.7%), pyrexia (2.4%), stomatitis (2.4%), acute kidney injury (2.0%), pneumonitis (1.6%), COVID-19 (1.2%), death not otherwise specified (1.2%), diarrhea (1.2%), dysphagia (1.2%), gastrostomy tube site complication (1.2%), and immune-mediated hepatitis (1.2%). Fatal adverse reactions occurred in 5% of patients, including death not otherwise specified (1.2%), acute renal failure (0.4%), hypercalcemia (0.4%), pulmonary hemorrhage (0.4%), dysphagia/malnutrition (0.4%), mesenteric thrombosis (0.4%), sepsis (0.4%), pneumonia (0.4%), COVID-19 (0.4%), respiratory failure (0.4%), cardiovascular disorder (0.4%), and gastrointestinal hemorrhage (0.4%). Permanent discontinuation of adjuvant KEYTRUDA due to an adverse reaction occurred in 17% of patients. The most frequent (≥1%) adverse reactions that led to permanent discontinuation of adjuvant KEYTRUDA were pneumonitis, colitis, immune-mediated hepatitis, and death not otherwise specified.

In KEYNOTE-048, KEYTRUDA monotherapy was discontinued due to adverse events in 12% of 300 patients with HNSCC; the most common adverse reactions leading to permanent discontinuation were sepsis (1.7%) and pneumonia (1.3%). The most common adverse reactions (≥20%) were fatigue (33%), constipation (20%), and rash (20%).

In KEYNOTE-048, when KEYTRUDA was administered in combination with platinum (cisplatin or carboplatin) and FU chemotherapy, KEYTRUDA was discontinued due to adverse reactions in 16% of 276 patients with HNSCC. The most common adverse reactions resulting in permanent discontinuation of KEYTRUDA were pneumonia (2.5%), pneumonitis (1.8%), and septic shock (1.4%). The most common adverse reactions (≥20%) were nausea (51%), fatigue (49%), constipation (37%), vomiting (32%), mucosal inflammation (31%), diarrhea (29%), decreased appetite (29%), stomatitis (26%), and cough (22%).

In KEYNOTE-012, KEYTRUDA was discontinued due to adverse reactions in 17% of 192 patients with HNSCC. Serious adverse reactions occurred in 45% of patients. The most frequent serious adverse reactions reported in at least 2% of patients were pneumonia, dyspnea, confusional state, vomiting, pleural effusion, and respiratory failure. The most common adverse reactions (≥20%) were fatigue, decreased appetite, and dyspnea. Adverse reactions occurring in patients with HNSCC were generally similar to those occurring in patients with melanoma or NSCLC who received KEYTRUDA as a monotherapy, with the exception of increased incidences of facial edema and new or worsening hypothyroidism.

In KEYNOTE-204, KEYTRUDA was discontinued due to adverse reactions in 14% of 148 patients with cHL. Serious adverse reactions occurred in 30% of patients receiving KEYTRUDA; those ≥1% were pneumonitis, pneumonia, pyrexia, myocarditis, acute kidney injury, febrile neutropenia, and sepsis. Three patients died from causes other than disease progression: 2 from complications after allogeneic HSCT and 1 from unknown cause. The most common adverse reactions (≥20%) were upper respiratory tract infection (41%), musculoskeletal pain (32%), diarrhea (22%), and pyrexia, fatigue, rash, and cough (20% each).

In KEYNOTE-087, KEYTRUDA was discontinued due to adverse reactions in 5% of 210 patients with cHL. Serious adverse reactions occurred in 16% of patients; those ≥1% were pneumonia, pneumonitis, pyrexia, dyspnea, GVHD, and herpes zoster. Two patients died from causes other than disease progression: 1 from GVHD after subsequent allogeneic HSCT and 1 from septic shock. The most common adverse reactions (≥20%) were fatigue (26%), pyrexia (24%), cough (24%), musculoskeletal pain (21%), diarrhea (20%), and rash (20%).

In KEYNOTE-170, KEYTRUDA was discontinued due to adverse reactions in 8% of 53 patients with PMBCL. Serious adverse reactions occurred in 26% of patients and included arrhythmia (4%), cardiac tamponade (2%), myocardial infarction (2%), pericardial effusion (2%), and pericarditis (2%). Six (11%) patients died within 30 days of start of treatment. The most common adverse reactions (≥20%) were musculoskeletal pain (30%), upper respiratory tract infection and pyrexia (28% each), cough (26%), fatigue (23%), and dyspnea (21%).

In KEYNOTE-A39, when KEYTRUDA was administered in combination with enfortumab vedotin to patients with locally advanced or metastatic urothelial cancer (n=440), fatal adverse reactions occurred in 3.9% of patients, including acute respiratory failure (0.7%), pneumonia (0.5%), and pneumonitis/ILD (0.2%). Serious adverse reactions occurred in 50% of patients receiving KEYTRUDA in combination with enfortumab vedotin; the serious adverse reactions in ≥2% of patients were rash (6%), acute kidney injury (5%), pneumonitis/ILD (4.5%), urinary tract infection (3.6%), diarrhea (3.2%), pneumonia (2.3%), pyrexia (2%), and hyperglycemia (2%). Permanent discontinuation of KEYTRUDA occurred in 27% of patients. The most common adverse reactions (≥2%) resulting in permanent discontinuation of KEYTRUDA were pneumonitis/ILD (4.8%) and rash (3.4%). The most common adverse reactions (≥20%) occurring in patients treated with KEYTRUDA in combination with enfortumab vedotin were rash (68%), peripheral neuropathy (67%), fatigue (51%), pruritus (41%), diarrhea (38%), alopecia (35%), weight loss (33%), decreased appetite (33%), nausea (26%), constipation (26%), dry eye (24%), dysgeusia (21%), and urinary tract infection (21%).

In KEYNOTE-052, KEYTRUDA was discontinued due to adverse reactions in 11% of 370 patients with locally advanced or metastatic urothelial carcinoma. Serious adverse reactions occurred in 42% of patients; those ≥2% were urinary tract infection, hematuria, acute kidney injury, pneumonia, and urosepsis. The most common adverse reactions (≥20%) were fatigue (38%), musculoskeletal pain (24%), decreased appetite (22%), constipation (21%), rash (21%), and diarrhea (20%).

In KEYNOTE-045, KEYTRUDA was discontinued due to adverse reactions in 8% of 266 patients with locally advanced or metastatic urothelial carcinoma. The most common adverse reaction resulting in permanent discontinuation of KEYTRUDA was pneumonitis (1.9%). Serious adverse reactions occurred in 39% of KEYTRUDA-treated patients; those ≥2% were urinary tract infection, pneumonia, anemia, and pneumonitis. The most common adverse reactions (≥20%) in patients who received KEYTRUDA were fatigue (38%), musculoskeletal pain (32%), pruritus (23%), decreased appetite (21%), nausea (21%), and rash (20%).

In KEYNOTE-057, KEYTRUDA was discontinued due to adverse reactions in 11% of 148 patients with high-risk NMIBC. The most common adverse reaction resulting in permanent discontinuation of KEYTRUDA was pneumonitis (1.4%). Serious adverse reactions occurred in 28% of patients; those ≥2% were pneumonia (3%), cardiac ischemia (2%), colitis (2%), pulmonary embolism (2%), sepsis (2%), and urinary tract infection (2%). The most common adverse reactions (≥20%) were fatigue (29%), diarrhea (24%), and rash (24%).

Adverse reactions occurring in patients with MSI-H or dMMR CRC were similar to those occurring in patients with melanoma or NSCLC who received KEYTRUDA as a monotherapy.

In KEYNOTE-158 and KEYNOTE-164, adverse reactions occurring in patients with MSI-H or dMMR cancer were similar to those occurring in patients with other solid tumors who received KEYTRUDA as a single agent.

In KEYNOTE-811, fatal adverse reactions occurred in 3 patients who received KEYTRUDA in combination with trastuzumab and CAPOX (capecitabine plus oxaliplatin) or FP (5-FU plus cisplatin) and included pneumonitis in 2 patients and hepatitis in 1 patient. KEYTRUDA was discontinued due to adverse reactions in 13% of 350 patients with locally advanced unresectable or metastatic HER2-positive gastric or GEJ adenocarcinoma. Adverse reactions resulting in permanent discontinuation of KEYTRUDA in ≥1% of patients were pneumonitis (2.0%) and pneumonia (1.1%). In the KEYTRUDA arm vs placebo, there was a difference of ≥5% incidence between patients treated with KEYTRUDA vs standard of care for diarrhea (53% vs 47%), rash (35% vs 28%), hypothyroidism (11% vs 5%), and pneumonia (11% vs 5%).

In KEYNOTE-859, when KEYTRUDA was administered in combination with fluoropyrimidine- and platinum-containing chemotherapy, serious adverse reactions occurred in 45% of 785 patients. Serious adverse reactions in >2% of patients included pneumonia (4.1%), diarrhea (3.9%), hemorrhage (3.9%), and vomiting (2.4%). Fatal adverse reactions occurred in 8% of patients who received KEYTRUDA, including infection (2.3%) and thromboembolism (1.3%). KEYTRUDA was permanently discontinued due to adverse reactions in 15% of patients. The most common adverse reactions resulting in permanent discontinuation of KEYTRUDA (≥1%) were infections (1.8%) and diarrhea (1.0%). The most common adverse reactions (reported in ≥20%) in patients receiving KEYTRUDA in combination with chemotherapy were peripheral neuropathy (47%), nausea (46%), fatigue (40%), diarrhea (36%), vomiting (34%), decreased appetite (29%), abdominal pain (26%), palmar-plantar erythrodysesthesia syndrome (25%), constipation (22%), and weight loss (20%).

In KEYNOTE-590, when KEYTRUDA was administered with cisplatin and fluorouracil to patients with metastatic or locally advanced esophageal or GEJ (tumors with epicenter 1 to 5 centimeters above the GEJ) carcinoma who were not candidates for surgical resection or definitive chemoradiation, KEYTRUDA was discontinued due to adverse reactions in 15% of 370 patients. The most common adverse reactions resulting in permanent discontinuation of KEYTRUDA (≥1%) were pneumonitis (1.6%), acute kidney injury (1.1%), and pneumonia (1.1%). The most common adverse reactions (≥20%) with KEYTRUDA in combination with chemotherapy were nausea (67%), fatigue (57%), decreased appetite (44%), constipation (40%), diarrhea (36%), vomiting (34%), stomatitis (27%), and weight loss (24%).

Adverse reactions occurring in patients with esophageal cancer who received KEYTRUDA as a monotherapy were similar to those occurring in patients with melanoma or NSCLC who received KEYTRUDA as a monotherapy.

In KEYNOTE-A18, when KEYTRUDA was administered with CRT (cisplatin plus external beam radiation therapy [EBRT] followed by brachytherapy [BT]) to patients with FIGO 2014 Stage III-IVA cervical cancer, fatal adverse reactions occurred in 1.4% of 294 patients, including 1 case each (0.3%) of large intestinal perforation, urosepsis, sepsis, and vaginal hemorrhage. Serious adverse reactions occurred in 34% of patients; those ≥1% included urinary tract infection (3.1%), urosepsis (1.4%), and sepsis (1%). KEYTRUDA was discontinued for adverse reactions in 9% of patients. The most common adverse reaction (≥1%) resulting in permanent discontinuation was diarrhea (1%). For patients treated with KEYTRUDA in combination with CRT, the most common adverse reactions (≥10%) were nausea (56%), diarrhea (51%), urinary tract infection (35%), vomiting (34%), fatigue (28%), hypothyroidism (23%), constipation (20%), weight loss (19%), decreased appetite (18%), pyrexia (14%), abdominal pain and hyperthyroidism (13% each), dysuria and rash (12% each), back and pelvic pain (11% each), and COVID-19 (10%).

In KEYNOTE-826, when KEYTRUDA was administered in combination with paclitaxel and cisplatin or paclitaxel and carboplatin, with or without bevacizumab (n=307), to patients with persistent, recurrent, or first-line metastatic cervical cancer regardless of tumor PD-L1 expression who had not been treated with chemotherapy except when used concurrently as a radio-sensitizing agent, fatal adverse reactions occurred in 4.6% of patients, including 3 cases of hemorrhage, 2 cases each of sepsis and due to unknown causes, and 1 case each of acute myocardial infarction, autoimmune encephalitis, cardiac arrest, cerebrovascular accident, femur fracture with perioperative pulmonary embolus, intestinal perforation, and pelvic infection. Serious adverse reactions occurred in 50% of patients receiving KEYTRUDA in combination with chemotherapy with or without bevacizumab; those ≥3% were febrile neutropenia (6.8%), urinary tract infection (5.2%), anemia (4.6%), and acute kidney injury and sepsis (3.3% each).

KEYTRUDA was discontinued in 15% of patients due to adverse reactions. The most common adverse reaction resulting in permanent discontinuation (≥1%) was colitis (1%).

For patients treated with KEYTRUDA, chemotherapy, and bevacizumab (n=196), the most common adverse reactions (≥20%) were peripheral neuropathy (62%), alopecia (58%), anemia (55%), fatigue/asthenia (53%), nausea and neutropenia (41% each), diarrhea (39%), hypertension and thrombocytopenia (35% each), constipation and arthralgia (31% each), vomiting (30%), urinary tract infection (27%), rash (26%), leukopenia (24%), hypothyroidism (22%), and decreased appetite (21%).

For patients treated with KEYTRUDA in combination with chemotherapy with or without bevacizumab, the most common adverse reactions (≥20%) were peripheral neuropathy (58%), alopecia (56%), fatigue (47%), nausea (40%), diarrhea (36%), constipation (28%), arthralgia (27%), vomiting (26%), hypertension and urinary tract infection (24% each), and rash (22%).

In KEYNOTE-158, KEYTRUDA was discontinued due to adverse reactions in 8% of 98 patients with previously treated recurrent or metastatic cervical cancer. Serious adverse reactions occurred in 39% of patients receiving KEYTRUDA; the most frequent included anemia (7%), fistula, hemorrhage, and infections [except urinary tract infections] (4.1% each). The most common adverse reactions (≥20%) were fatigue (43%), musculoskeletal pain (27%), diarrhea (23%), pain and abdominal pain (22% each), and decreased appetite (21%).

In KEYNOTE-394, KEYTRUDA was discontinued due to adverse reactions in 13% of 299 patients with previously treated hepatocellular carcinoma. The most common adverse reaction resulting in permanent discontinuation of KEYTRUDA was ascites (2.3%). The most common adverse reactions in patients receiving KEYTRUDA (≥10%) were pyrexia (18%), rash (18%), diarrhea (16%), decreased appetite (15%), pruritus (12%), upper respiratory tract infection (11%), cough (11%), and hypothyroidism (10%).

In KEYNOTE-966, when KEYTRUDA was administered in combination with gemcitabine and cisplatin, KEYTRUDA was discontinued for adverse reactions in 15% of 529 patients with locally advanced unresectable or metastatic biliary tract cancer. The most common adverse reaction resulting in permanent discontinuation of KEYTRUDA (≥1%) was pneumonitis (1.3%). Adverse reactions leading to the interruption of KEYTRUDA occurred in 55% of patients. The most common adverse reactions or laboratory abnormalities leading to interruption of KEYTRUDA (≥2%) were decreased neutrophil count (18%), decreased platelet count (10%), anemia (6%), decreased white blood cell count (4%), pyrexia (3.8%), fatigue (3.0%), cholangitis (2.8%), increased ALT (2.6%), increased AST (2.5%), and biliary obstruction (2.3%).

In KEYNOTE-017 and KEYNOTE-913, adverse reactions occurring in patients with MCC (n=105) were generally similar to those occurring in patients with melanoma or NSCLC who received KEYTRUDA as a single agent.

In KEYNOTE-426, when KEYTRUDA was administered in combination with axitinib, fatal adverse reactions occurred in 3.3% of 429 patients. Serious adverse reactions occurred in 40% of patients, the most frequent (≥1%) were hepatotoxicity (7%), diarrhea (4.2%), acute kidney injury (2.3%), dehydration (1%), and pneumonitis (1%). Permanent discontinuation due to an adverse reaction occurred in 31% of patients; KEYTRUDA only (13%), axitinib only (13%), and the combination (8%); the most common were hepatotoxicity (13%), diarrhea/colitis (1.9%), acute kidney injury (1.6%), and cerebrovascular accident (1.2%). The most common adverse reactions (≥20%) were diarrhea (56%), fatigue/asthenia (52%), hypertension (48%), hepatotoxicity (39%), hypothyroidism (35%), decreased appetite (30%), palmar-plantar erythrodysesthesia (28%), nausea (28%), stomatitis/mucosal inflammation (27%), dysphonia (25%), rash (25%), cough (21%), and constipation (21%).

In KEYNOTE-564, when KEYTRUDA was administered as a single agent for the adjuvant treatment of renal cell carcinoma, serious adverse reactions occurred in 20% of patients receiving KEYTRUDA; the serious adverse reactions (≥1%) were acute kidney injury, adrenal insufficiency, pneumonia, colitis, and diabetic ketoacidosis (1% each). Fatal adverse reactions occurred in 0.2% including 1 case of pneumonia. Discontinuation of KEYTRUDA due to adverse reactions occurred in 21% of 488 patients; the most common (≥1%) were increased ALT (1.6%), colitis (1%), and adrenal insufficiency (1%). The most common adverse reactions (≥20%) were musculoskeletal pain (41%), fatigue (40%), rash (30%), diarrhea (27%), pruritus (23%), and hypothyroidism (21%).

In KEYNOTE-868, when KEYTRUDA was administered in combination with chemotherapy (paclitaxel and carboplatin) to patients with advanced or recurrent endometrial carcinoma (n=382), serious adverse reactions occurred in 35% of patients receiving KEYTRUDA in combination with chemotherapy, compared to 19% of patients receiving placebo in combination with chemotherapy (n=377). Fatal adverse reactions occurred in 1.6% of patients receiving KEYTRUDA in combination with chemotherapy, including COVID-19 (0.5%) and cardiac arrest (0.3%). KEYTRUDA was discontinued for an adverse reaction in 14% of patients. Adverse reactions occurring in patients treated with KEYTRUDA and chemotherapy were generally similar to those observed with KEYTRUDA alone or chemotherapy alone, with the exception of rash (33% all Grades; 2.9% Grades 3-4).

Adverse reactions occurring in patients with MSI-H or dMMR endometrial carcinoma who received KEYTRUDA as a single agent were similar to those occurring in patients with melanoma or NSCLC who received KEYTRUDA as a single agent.

Adverse reactions occurring in patients with TMB-H cancer were similar to those occurring in patients with other solid tumors who received KEYTRUDA as a single agent.

Adverse reactions occurring in patients with recurrent or metastatic cSCC or locally advanced cSCC were similar to those occurring in patients with melanoma or NSCLC who received KEYTRUDA as a monotherapy.

In KEYNOTE-522, when KEYTRUDA was administered with neoadjuvant chemotherapy (carboplatin and paclitaxel followed by doxorubicin or epirubicin and cyclophosphamide) followed by surgery and continued adjuvant treatment with KEYTRUDA as a single agent (n=778) to patients with newly diagnosed, previously untreated, high-risk early-stage TNBC, fatal adverse reactions occurred in 0.9% of patients, including 1 each of adrenal crisis, autoimmune encephalitis, hepatitis, pneumonia, pneumonitis, pulmonary embolism, and sepsis in association with multiple organ dysfunction syndrome and myocardial infarction. Serious adverse reactions occurred in 44% of patients receiving KEYTRUDA; those ≥2% were febrile neutropenia (15%), pyrexia (3.7%), anemia (2.6%), and neutropenia (2.2%). KEYTRUDA was discontinued in 20% of patients due to adverse reactions. The most common reactions (≥1%) resulting in permanent discontinuation were increased ALT (2.7%), increased AST (1.5%), and rash (1%). The most common adverse reactions (≥20%) in patients receiving KEYTRUDA were fatigue (70%), nausea (67%), alopecia (61%), rash (52%), constipation (42%), diarrhea and peripheral neuropathy (41% each), stomatitis (34%), vomiting (31%), headache (30%), arthralgia (29%), pyrexia (28%), cough (26%), abdominal pain (24%), decreased appetite (23%), insomnia (21%), and myalgia (20%).

In KEYNOTE-355, when KEYTRUDA and chemotherapy (paclitaxel, paclitaxel protein-bound, or gemcitabine and carboplatin) were administered to patients with locally recurrent unresectable or metastatic TNBC who had not been previously treated with chemotherapy in the metastatic setting (n=596), fatal adverse reactions occurred in 2.5% of patients, including cardio-respiratory arrest (0.7%) and septic shock (0.3%). Serious adverse reactions occurred in 30% of patients receiving KEYTRUDA in combination with chemotherapy; the serious reactions in ≥2% were pneumonia (2.9%), anemia (2.2%), and thrombocytopenia (2%). KEYTRUDA was discontinued in 11% of patients due to adverse reactions. The most common reactions resulting in permanent discontinuation (≥1%) were increased ALT (2.2%), increased AST (1.5%), and pneumonitis (1.2%). The most common adverse reactions (≥20%) in patients receiving KEYTRUDA in combination with chemotherapy were fatigue (48%), nausea (44%), alopecia (34%), diarrhea and constipation (28% each), vomiting and rash (26% each), cough (23%), decreased appetite (21%), and headache (20%).

Lactation
Because of the potential for serious adverse reactions in breastfed children, advise women not to breastfeed during treatment and for 4 months after the last dose.

Pediatric Use
In KEYNOTE-051, 173 pediatric patients (65 pediatric patients aged 6 months to younger than 12 years and 108 pediatric patients aged 12 years to 17 years) were administered KEYTRUDA 2 mg/kg every 3 weeks. The median duration of exposure was 2.1 months (range: 1 day to 25 months).

Adverse reactions that occurred at a ≥10% higher rate in pediatric patients when compared to adults were pyrexia (33%), leukopenia (30%), vomiting (29%), neutropenia (28%), headache (25%), abdominal pain (23%), thrombocytopenia (22%), Grade 3 anemia (17%), decreased lymphocyte count (13%), and decreased white blood cell count (11%).

Geriatric Use
Of the 564 patients with locally advanced or metastatic urothelial cancer treated with KEYTRUDA in combination with enfortumab vedotin, 44% (n=247) were 65-74 years and 26% (n=144) were 75 years or older. No overall differences in safety or effectiveness were observed between patients 65 years of age or older and younger patients. Patients 75 years of age or older treated with KEYTRUDA in combination with enfortumab vedotin experienced a higher incidence of fatal adverse reactions than younger patients. The incidence of fatal adverse reactions was 4% in patients younger than 75 and 7% in patients 75 years or older.

Additional Selected KEYTRUDA Indications in the U.S.
Melanoma
KEYTRUDA is indicated for the treatment of patients with unresectable or metastatic melanoma.

KEYTRUDA is indicated for the adjuvant treatment of adult and pediatric (12 years and older) patients with Stage IIB, IIC, or III melanoma following complete resection.

Non-Small Cell Lung Cancer
KEYTRUDA, in combination with pemetrexed and platinum chemotherapy, is indicated for the first-line treatment of patients with metastatic nonsquamous non-small cell lung cancer (NSCLC), with no EGFR or ALK genomic tumor aberrations.

KEYTRUDA, in combination with carboplatin and either paclitaxel or paclitaxel protein-bound, is indicated for the first-line treatment of patients with metastatic squamous NSCLC.

KEYTRUDA, as a single agent, is indicated for the first-line treatment of patients with NSCLC expressing PD-L1 [Tumor Proportion Score (TPS) ≥1%] as determined by an FDA-approved test, with no EGFR or ALK genomic tumor aberrations, and is:

Stage III where patients are not candidates for surgical resection or definitive chemoradiation, or
metastatic.
KEYTRUDA, as a single agent, is indicated for the treatment of patients with metastatic NSCLC whose tumors express PD-L1 (TPS ≥1%) as determined by an FDA-approved test, with disease progression on or after platinum-containing chemotherapy. Patients with EGFR or ALK genomic tumor aberrations should have disease progression on FDA-approved therapy for these aberrations prior to receiving KEYTRUDA.

KEYTRUDA is indicated for the treatment of patients with resectable (tumors ≥4 cm or node positive) NSCLC in combination with platinum-containing chemotherapy as neoadjuvant treatment, and then continued as a single agent as adjuvant treatment after surgery.

KEYTRUDA, as a single agent, is indicated as adjuvant treatment following resection and platinum-based chemotherapy for adult patients with Stage IB (T2a ≥4 cm), II, or IIIA NSCLC.

Malignant Pleural Mesothelioma
KEYTRUDA, in combination with pemetrexed and platinum chemotherapy, is indicated for the first-line treatment of adult patients with unresectable advanced or metastatic malignant pleural mesothelioma (MPM).

Head and Neck Squamous Cell Cancer
KEYTRUDA is indicated for the treatment of adult patients with resectable locally advanced head and neck squamous cell carcinoma (HNSCC) whose tumors express PD-L1 [Combined Positive Score (CPS) ≥1] as determined by an FDA-approved test, as a single agent as neoadjuvant treatment, continued as adjuvant treatment in combination with radiotherapy (RT) with or without cisplatin and then as a single agent.

KEYTRUDA, in combination with platinum and fluorouracil (FU), is indicated for the first-line treatment of patients with metastatic or with unresectable, recurrent HNSCC.

KEYTRUDA, as a single agent, is indicated for the first-line treatment of patients with metastatic or with unresectable, recurrent HNSCC whose tumors express PD-L1 (CPS ≥1) as determined by an FDA-approved test.

KEYTRUDA, as a single agent, is indicated for the treatment of patients with recurrent or metastatic HNSCC with disease progression on or after platinum-containing chemotherapy.

Classical Hodgkin Lymphoma
KEYTRUDA is indicated for the treatment of adult patients with relapsed or refractory classical Hodgkin lymphoma (cHL).

KEYTRUDA is indicated for the treatment of pediatric patients with refractory cHL, or cHL that has relapsed after 2 or more lines of therapy.

Primary Mediastinal Large B-Cell Lymphoma
KEYTRUDA is indicated for the treatment of adult and pediatric patients with refractory primary mediastinal large B-cell lymphoma (PMBCL), or who have relapsed after 2 or more prior lines of therapy. KEYTRUDA is not recommended for treatment of patients with PMBCL who require urgent cytoreductive therapy.

Microsatellite Instability-High or Mismatch Repair Deficient Cancer
KEYTRUDA is indicated for the treatment of adult and pediatric patients with unresectable or metastatic microsatellite instability-high (MSI-H) or mismatch repair deficient (dMMR) solid tumors, as determined by an FDA-approved test, that have progressed following prior treatment and who have no satisfactory alternative treatment options.

Microsatellite Instability-High or Mismatch Repair Deficient Colorectal Cancer
KEYTRUDA is indicated for the treatment of patients with unresectable or metastatic MSI-H or dMMR colorectal cancer (CRC) as determined by an FDA-approved test.

Gastric Cancer
KEYTRUDA, in combination with trastuzumab, fluoropyrimidine- and platinum-containing chemotherapy, is indicated for the first-line treatment of adults with locally advanced unresectable or metastatic HER2-positive gastric or gastroesophageal junction (GEJ) adenocarcinoma whose tumors express PD-L1 (CPS ≥1) as determined by an FDA-approved test.

KEYTRUDA, in combination with fluoropyrimidine- and platinum-containing chemotherapy, is indicated for the first-line treatment of adults with locally advanced unresectable or metastatic HER2-negative gastric or gastroesophageal junction (GEJ) adenocarcinoma whose tumors express PD-L1 (CPS ≥ 1) as determined by an FDA approved test.

Esophageal Cancer
KEYTRUDA is indicated for the treatment of patients with locally advanced or metastatic esophageal or gastroesophageal junction (GEJ) (tumors with epicenter 1 to 5 centimeters above the GEJ) carcinoma that is not amenable to surgical resection or definitive chemoradiation either:

in combination with platinum- and fluoropyrimidine-based chemotherapy for patients with tumors that express PD-L1 (CPS ≥ 1), or
as a single agent after one or more prior lines of systemic therapy for patients with tumors of squamous cell histology that express PD-L1 (CPS ≥10) as determined by an FDA-approved test.
Cervical Cancer
KEYTRUDA, in combination with chemoradiotherapy (CRT), is indicated for the treatment of patients with locally advanced cervical cancer involving the lower third of the vagina, with or without extension to pelvic sidewall, or hydronephrosis/non-functioning kidney, or spread to adjacent pelvic organs (FIGO 2014 Stage III-IVA).

KEYTRUDA, in combination with chemotherapy, with or without bevacizumab, is indicated for the treatment of patients with persistent, recurrent, or metastatic cervical cancer whose tumors express PD-L1 (CPS ≥1) as determined by an FDA-approved test.

KEYTRUDA, as a single agent, is indicated for the treatment of patients with recurrent or metastatic cervical cancer with disease progression on or after chemotherapy whose tumors express PD-L1 (CPS ≥1) as determined by an FDA-approved test.

Hepatocellular Carcinoma
KEYTRUDA is indicated for the treatment of patients with hepatocellular carcinoma (HCC) secondary to hepatitis B who have received prior systemic therapy other than a PD-1/PD-L1-containing regimen.

Biliary Tract Cancer
KEYTRUDA, in combination with gemcitabine and cisplatin, is indicated for the treatment of patients with locally advanced unresectable or metastatic biliary tract cancer (BTC).

Merkel Cell Carcinoma
KEYTRUDA is indicated for the treatment of adult and pediatric patients with recurrent locally advanced or metastatic Merkel cell carcinoma (MCC).

Renal Cell Carcinoma
KEYTRUDA, in combination with axitinib, is indicated for the first-line treatment of adult patients with advanced renal cell carcinoma (RCC).

KEYTRUDA is indicated for the adjuvant treatment of patients with RCC at intermediate-high or high risk of recurrence following nephrectomy, or following nephrectomy and resection of metastatic lesions.

Endometrial Carcinoma
KEYTRUDA, in combination with carboplatin and paclitaxel, followed by KEYTRUDA as a single agent, is indicated for the treatment of adult patients with primary advanced or recurrent endometrial carcinoma.

KEYTRUDA, as a single agent, is indicated for the treatment of adult patients with advanced endometrial carcinoma that is MSI-H or dMMR, as determined by an FDA-approved test, who have disease progression following prior systemic therapy in any setting and are not candidates for curative surgery or radiation.

Tumor Mutational Burden-High Cancer
KEYTRUDA is indicated for the treatment of adult and pediatric patients with unresectable or metastatic tumor mutational burden-high (TMB-H) [≥10 mutations/megabase (mut/Mb)] solid tumors, as determined by an FDA-approved test, that have progressed following prior treatment and who have no satisfactory alternative treatment options.

This indication is approved under accelerated approval based on tumor response rate and durability of response. Continued approval for this indication may be contingent upon verification and description of clinical benefit in the confirmatory trials. The safety and effectiveness of KEYTRUDA in pediatric patients with TMB-H central nervous system cancers have not been established.

Cutaneous Squamous Cell Carcinoma
KEYTRUDA is indicated for the treatment of patients with recurrent or metastatic cutaneous squamous cell carcinoma (cSCC) or locally advanced cSCC that is not curable by surgery or radiation.

Triple-Negative Breast Cancer
KEYTRUDA is indicated for the treatment of patients with high-risk early-stage triple-negative breast cancer (TNBC) in combination with chemotherapy as neoadjuvant treatment, and then continued as a single agent as adjuvant treatment after surgery.

KEYTRUDA, in combination with chemotherapy, is indicated for the treatment of patients with locally recurrent unresectable or metastatic TNBC whose tumors express PD-L1 (CPS ≥10) as determined by an FDA-approved test.

(Press release, Merck & Co, OCT 18, 2025, View Source [SID1234656769])

KEYTRUDA® (pembrolizumab) Plus Chemotherapy With or Without Bevacizumab Reduced Risk of Disease Progression or Death Versus Chemotherapy With or Without Bevacizumab in Certain Patients With Platinum-Resistant Recurrent Ovarian Cancer

On October 18, 2025 Merck (NYSE: MRK), known as MSD outside of the United States and Canada, reported the first presentation of results from the pivotal Phase 3 KEYNOTE-B96 trial, also known as ENGOT-ov65, evaluating KEYTRUDA (pembrolizumab), Merck’s anti-PD-1 therapy, in combination with chemotherapy (paclitaxel) with or without bevacizumab for the treatment of patients with platinum-resistant recurrent ovarian cancer. These late-breaking data will be presented today during a Presidential Symposium session at the European Society for Medical Oncology (ESMO) (Free ESMO Whitepaper) Congress 2025 (Presentation #LBA3).

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At the first interim analysis, with a median study follow-up of 15.6 months, KEYTRUDA plus chemotherapy with or without bevacizumab (n=322) demonstrated a statistically significant and clinically meaningful improvement in progression-free survival (PFS), the study’s primary endpoint, reducing the risk of disease progression or death by 30% (HR=0.70 [95% CI, 0.58-0.84]; p<0.0001) in the all comers population of patients with platinum-resistant recurrent ovarian cancer compared to placebo plus chemotherapy with or without bevacizumab (n=321). The 12-month PFS rate for these patients receiving the KEYTRUDA regimen was 33.1% (95% CI, 27.7-38.5) versus 21.3% (95% CI, 16.6-26.4) for patients receiving the placebo regimen. In patients whose tumors express PD-L1 (Combined Positive Score [CPS] ≥1), KEYTRUDA plus chemotherapy with or without bevacizumab (n=234) reduced the risk of disease progression or death by 28% (HR=0.72 [95% CI, 0.58-0.89]; p=0.0014) compared to placebo plus chemotherapy with or without bevacizumab (n=232). The 12-month PFS rate was 35.2% (95% CI, 28.8-41.7) for the KEYTRUDA regimen versus 22.6% (95% CI, 17.0-28.7) for the placebo regimen.

"There are very few treatments we can offer patients living with platinum-resistant recurrent ovarian cancer that are able to reduce the risk of disease progression or death," said Dr. Nicoletta Colombo, director of the Gynecologic Oncology Program at the European Institute of Oncology in Milan, Italy. "Results from KEYNOTE-B96 have the potential to mark a significant step forward in the treatment of platinum-resistant recurrent ovarian cancer and demonstrate that adding pembrolizumab to chemotherapy, with or without bevacizumab, could potentially be an additional effective option for these patients."

At the second interim analysis, with a median study follow-up of 26.6 months, the KEYTRUDA regimen also demonstrated a statistically significant and clinically meaningful improvement in overall survival (OS), a key secondary endpoint, in patients whose tumors express PD-L1 (CPS ≥1), reducing the risk of death by 24% (HR=0.76 [95% CI, 0.61-0.94]; p=0.0053) compared to placebo plus chemotherapy with or without bevacizumab. The 12-month OS rate for patients receiving the KEYTRUDA regimen was 69.1% versus 59.3% for patients receiving the placebo regimen. Eighteen-month OS rates were 51.5% and 38.9%, respectively.

"These results build upon the success of KEYTRUDA in gynecologic cancers and support the potential use of KEYTRUDA for patients with platinum-resistant ovarian cancer," said Dr. Gursel Aktan, vice president, global clinical development, Merck Research Laboratories. "As the first immunotherapy with data demonstrating improved survival in certain patients with platinum-resistant recurrent ovarian cancer, this KEYTRUDA-based regimen underscores our commitment to helping to provide patients with more treatment options to meet their unique needs. These data have the potential to change the treatment paradigm for patients like these with platinum-resistant recurrent ovarian cancer."

Treatment-related adverse events (TRAEs) occurred in 97.8% of patients receiving the KEYTRUDA regimen (n=320) and 95.3% of patients receiving the placebo regimen (n=318); Grade 3-5 TRAEs occurred in 67.5% versus 55.3%, respectively. TRAEs led to death in 0.9% of patients receiving the KEYTRUDA regimen and 1.6% of patients receiving the placebo regimen. No new safety concerns were identified.

Immune-mediated adverse events (AEs) and infusion reactions of any grade occurred in 39.1% of patients receiving the KEYTRUDA regimen and 18.9% of patients receiving the placebo regimen. The most common of these events (occurring in ≥10% of patients) was hypothyroidism (17.8%) in patients receiving the KEYTRUDA regimen. Immune-mediated AEs led to death in 0.6% of patients in the KEYTRUDA arm and in no patients in the placebo arm.

Based on these data from the first and second interim analyses of the KEYNOTE-B96 trial, the U.S. Food and Drug Administration (FDA) has accepted for priority review a new supplemental Biologics License Application (sBLA) seeking approval of KEYTRUDA in combination with chemotherapy with or without bevacizumab for the treatment of patients with platinum-resistant recurrent ovarian cancer. The FDA has set a Prescription Drug User Fee Act (PDUFA), or target action, date of Feb. 20, 2026. As previously announced, in the final analysis of the trial, KEYNOTE-B96 also met its secondary endpoint of OS for all comers. These final analysis data will be presented at an upcoming medical meeting.

KEYTRUDA is not approved to treat ovarian cancer (see selected KEYTRUDA indications in the U.S. below). LYNPARZA (olaparib), which is being jointly developed and commercialized by AstraZeneca and Merck, has three approved ovarian cancer indications in the U.S.: in first-line maintenance treatment of BRCA-mutated advanced ovarian cancer, following complete or partial response to first-line platinum-based chemotherapy; in first-line maintenance treatment of HRD-positive advanced ovarian cancer in combination with bevacizumab, following complete or partial response to first-line platinum-based chemotherapy; and in maintenance treatment of BRCA-mutated recurrent ovarian cancer, following complete or partial response to platinum-based chemotherapy. For each of these indications, patients are selected for therapy based on an FDA-approved companion diagnostic for LYNPARZA (see indications for LYNPARZA below).

As announced, data from the REJOICE-Ovarian01 trial in collaboration with Daiichi Sankyo evaluating raludotatug deruxtecan (R-DXd) in patients with platinum-resistant, high-grade ovarian, primary peritoneal or fallopian tube cancer will be presented at the 2025 ESMO (Free ESMO Whitepaper) Congress. R-DXd was recently granted Breakthrough Therapy Designation by the U.S. FDA for the treatment of adult patients with platinum-resistant epithelial ovarian, primary peritoneal or fallopian tube cancers expressing CDH6 who have received prior treatment with bevacizumab, based in part on data from the REJOICE-Ovarian01 trial. R-DXd was discovered by Daiichi Sankyo and is being jointly developed by Daiichi Sankyo and Merck.

About KEYNOTE-B96/ENGOT-ov65
KEYNOTE-B96, also known as ENGOT-ov65, is a randomized, double-blind Phase 3 trial (ClinicalTrials.gov, NCT05116189) sponsored by Merck and conducted in collaboration with the European Network for Gynecologic Oncology Trial (ENGOT) groups investigating KEYTRUDA in combination with chemotherapy (paclitaxel) with or without bevacizumab compared to placebo plus chemotherapy with or without bevacizumab for the treatment of platinum-resistant recurrent ovarian cancer. The primary endpoint is PFS, and OS is a key secondary endpoint. The trial enrolled 643 patients who were randomized to receive either KEYTRUDA (400 mg intravenously every six weeks for approximately two years) plus paclitaxel with or without bevacizumab, or placebo plus paclitaxel with or without bevacizumab.

About platinum-resistant ovarian cancer
Ovarian cancer often begins in the fallopian tubes or on the outer surface of the ovaries. It is the eighth most commonly diagnosed cancer and the eighth leading cause of cancer death among women worldwide. Globally, there were more than 324,000 patients diagnosed with ovarian cancer and almost 207,000 deaths from the disease in 2022. In many regions, its incidence has been increasing, with estimates projecting a 42% increase in new cases worldwide by 2040. In the U.S., it is estimated there will be approximately 20,890 patients diagnosed with ovarian cancer and about 12,730 deaths from the disease in 2025.

The primary aim of first-line treatment is to delay disease progression for as long as possible with the intent to achieve long-term remission. Between 70% and 80% of patients diagnosed with advanced ovarian cancer will experience disease progression following standard treatment with platinum-based chemotherapy regimens. Approximately 25% of these patients develop resistance within six months of completing first-line platinum-based chemotherapy, and this is defined as primary platinum-resistant ovarian cancer. Prognosis is particularly poor for these patients and treatment options are limited.

(Press release, Merck & Co, OCT 18, 2025, View Source [SID1234656770])

Salubris Biotherapeutics Announces Dose Escalation Data for JK06, a 5T4-Targeted Antibody Drug Conjugate, at the European Society for Medical Oncology 2025 Congress

On October 18, 2025 Salubris Biotherapeutics, Inc. (SalubrisBio), a clinical-stage biotechnology company dedicated to discovering and developing novel complex biologic therapeutics, reported data from the dose escalation portion of the Phase 1/2 study of JK06, a 5T4-targeted antibody drug conjugate (ADC), in patients with unresectable locally advanced or metastatic cancer, including non-small cell lung cancer (NSCLC) and breast cancer, which is being presented at the European Society for Medical Oncology (ESMO) (Free ESMO Whitepaper) Congress.

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Data presented at ESMO (Free ESMO Whitepaper) include 34 patients enrolled in Europe with advanced relapsed/refractory solid tumors who were treated with JK06, once every three weeks, across five dose levels (1.5-8.0 mg/kg) in dose escalation. Among the 34 patients, 29 were response-evaluable, all having failed standard of care therapy, and among whom 83% had received three or more prior lines of treatment and 59% had received four or more prior lines of therapy at the time of enrollment.

Key efficacy findings among the 29 response-evaluable patients include:

6 patients attained confirmed partial responses (PRs) (21%).
Among 13 NSCLC patients, 5 attained confirmed PRs (ORR 38%), with the longest duration of response lasting 30 weeks.
Among 7 response-evaluable breast cancer patients, 1 attained a confirmed PR with a duration of response lasting 18 weeks.
PRs were observed at 3.0 mg/kg (1 NSCLC), 4.5 mg/kg (3 NSCLC and 1 breast cancer), and 6.0 mg/kg (1 NSCLC).
Treatment with JK06 has been generally well-tolerated with predominantly low grade (Grades 1 and 2), manageable toxicities, such as fatigue, alopecia, decreased appetite, dry eye and diarrhea. Among treatment-related adverse events (TRAEs) occurring in at least 5% of patients, only the following ≥ Grade 3 events were observed:

At dose levels 1.5-3.0 mg/kg (n=12 patients), 1 patient with Grade 3 peripheral neuropathy.
At dose level 4.5 mg/kg (n=15 patients), 1 patient with Grade 3 keratitis.
At dose levels 6.0-8.0 mg/kg (n=7 patients), 1 patient with Grade 3 fatigue, 1 patient with Grade 3 ALT increase, and 1 patient with Grade 5 pneumonitis.
Pharmacokinetic analysis demonstrated free monomethyl auristatin E (MMAE) levels that were favorable at dose levels up to 4.5 mg/kg.
"We are encouraged by the promising preliminary data demonstrating the combination of safety and efficacy of JK06 among heavily pre-treated metastatic solid tumors, including in NSCLC and breast cancer, supporting our belief that JK06 has the potential to be a first-in-class, differentiated therapy for patients with 5T4-expressing cancers," said Sam Murphy, Chief Executive Officer of Salubris Biotherapeutics. "We look forward to advancing the study into dose expansion in tumor-specific cohorts for NSCLC and breast cancer, while continuing to explore activity in other solid tumors known to overexpress 5T4, as we aim to improve outcomes for these patients with advanced, aggressive disease and limited therapeutic options."

The Phase 1/2 open-label, dose-escalation and expansion study (NCT06667960) to assess the safety, pharmacokinetics, and preliminary efficacy of JK06 is ongoing, and the cohort expansion phase, which is currently enrolling, will determine the recommended Phase 2 dose for further development.

Details of the ESMO (Free ESMO Whitepaper) presentation are as follows:

Title: A Phase 1/2 Study of JK06, a 5T4-Targeted Antibody Drug Conjugate (ADC), in Patients with Unresectable Locally Advanced or Metastatic Cancer
Presenter: Nuria Kotecki, M.D. at Institut Jules Bordet, Anderlecht, Belgium
Abstract #: 961P
Session: Developmental Therapeutics
Date/Time: Sunday, October 19, 2025 | 12:00 – 1:00 PM CEST

About JK06

JK06 is a first-in-class quadrivalent, biparatopic ADC that selectively targets 5T4 with a monomethyl auristatin E (MMAE) payload. 5T4 is an oncofetal protein that is overexpressed in a wide range of solid tumors, including NSCLC, breast, renal and genitourinary cancers, and is associated with more aggressive tumor progression and reduced survival. JK06 has demonstrated picomolar affinity for 5T4 and rapid internalization due to the biparatopic design. Together with stable, site-specific payload conjugation, JK06 has further demonstrated robust efficacy and a clean safety profile in non-clinical studies.

(Press release, Salubris Biotherapeutics, OCT 18, 2025, View Source [SID1234656756])