Colorectal CancerPhase 2NCT04895722
Evaluation of Co-formulated Pembrolizumab/Quavonlimab (MK-1308A) Versus Other Treatments in Participants With Microsatellite Instability-High (MSI-H) or Mismatch Repair Deficient (dMMR) Stage IV Colorectal Cancer (CRC) (MK-1308A-008/KEYSTEP-008).
A Phase 2 study testing Pembrolizumab, Pembrolizumab/Quavonlimab and Pembrolizumab/Favezelimab in people with Colorectal Cancer, run by Merck Sharp & Dohme LLC at 109 sites in 22 countries.
Trial summary
The purpose of this study is to assess the efficacy and safety of co-formulated pembrolizumab/quavonlimab versus other treatments in participants with MSI-H or dMMR Metastatic Stage IV Colorectal Cancer. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Colorectal Cancer
- What is being tested?
- Pembrolizumab, Pembrolizumab/Quavonlimab and Pembrolizumab/Favezelimab
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 302 participants
- Where
- 109 sitesin 22 countries
- Study dates
- 25 Jun 2021to 6 Aug 2026
- Phase
- Phase 2
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Has a histologically confirmed diagnosis of Stage IV CRC adenocarcinoma (as defined by American Joint Committee on Cancer [AJCC] version 8)
- Has locally confirmed dMMR/MSI-H
- Has a life expectancy of at least 3 months
- Female participants are eligible to participate if not pregnant or breastfeeding, and not a woman of childbearing potential (WOCBP), or if a WOCBP then uses a contraceptive method that is highly effective or is abstinent on a long-term and persistent basis, during the intervention period and for at least 120 days after the last dose of study intervention
- Has measurable disease per RECIST 1.1 as assessed by the site and verified by BICR
- Submit an archival (within 5 years of Screening) or newly obtained tumor tissue sample that has not been previously irradiated; formalin-fixed, paraffin embedded (FFPE) blocks are preferred to slides.
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- Has adequate organ function
- Cohort A:
- Has been previously treated for their Stage IV dMMR/MSI-H CRC and radiographically progressed on or after or could not tolerate standard treatment, which must include all of the following agents if approved and locally available in the country where the participant is randomized:
- Fluoropyrimidine, irinotecan and oxaliplatin (capecitabine is acceptable as equivalent to fluorouracil in prior therapy)
- With or without an anti-vascular endothelial growth factor (VEGF) monoclonal antibody (e.g., bevacizumab)
- At least one of the anti-epidermal growth factor receptor (EGFR) monoclonal antibodies (cetuximab or panitumumab) for rat sarcoma viral oncogene homolog (RAS) wild-type participants with left-sided tumors. Prior EGFR therapy is optional for patients with right sided RAS Wild-type (WT) tumors.
- Cohort B:
- Has untreated Stage IV dMMR/MSI-H CRC with no prior chemotherapy or immunotherapy for this disease
Who cannot join
- Has received prior therapy with an agent directed to another stimulatory or coinhibitory T-cell receptor
- Has received prior systemic anticancer therapy including investigational agents within 4 weeks before the first dose of study intervention
- Has not recovered adequately from a surgery procedure, and/or has any complications from a prior surgery before starting study intervention
- Has received prior radiotherapy within 2 weeks of start of study intervention
- Has received a live or live-attenuated vaccine within 30 days before the first dose of study intervention
- Is currently participating in or has participated in a study of an investigational agent or has used an investigational device within 4 weeks before the first dose of study intervention
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- Has a diagnosis of immunodeficiency or is receiving chronic systemic steroid therapy (in dosing exceeding 10 mg daily of prednisone equivalent) or any other form of immunosuppressive therapy within 7 days prior to the first dose of study medication
- Has a known additional malignancy that is progressing or has required active treatment within the past 2 years
- Has known active central nervous system (CNS) metastases and/or carcinomatous meningitis
- Has severe hypersensitivity (≥Grade 3) to pembrolizumab, quavonlimab, favezelimab, vibostolimab, MK-4830, and/or any of their excipients
- Has an active autoimmune disease that has required systemic treatment in past 2 years (i.e., with use of disease modifying agents, corticosteroids or immunosuppressive drugs)
- Has a history of (noninfectious) pneumonitis that required steroids or has current pneumonitis
- Has a history of acute or chronic pancreatitis
- Has neuromuscular disorders associated with an elevated creatine kinase
- Has urine protein ≥1 gram/24 hours
- Has an active infection requiring systemic therapy (e.g., tuberculosis, known viral or bacterial infections, etc.)
- Has a known history of Human Immunodeficiency Virus (HIV) infection
- Concurrent active Hepatitis B (defined as Hepatitis B surface antigen [HBsAg] positive and/or detectable Hepatitis B Virus [HBV] deoxyribonucleic acid [DNA]) and Hepatitis C virus (defined as anti-HCV antibody positive and detectable HCV ribonucleic acid [RNA] infection
- Has clinically significant cardiac disease, including unstable angina, acute myocardial infarction within 6 months from Day 1 of study intervention administration, or New York Heart Association Class III or IV congestive heart failure. Medically controlled arrhythmia stable on medication is permitted.
- Has present or progressive accumulation of pleural, ascitic, or pericardial fluid requiring drainage or diuretic drugs within 2 weeks before randomization/allocation
- Has a history or current evidence of any condition, therapy, or laboratory abnormality that might confound the results of the study, interfere with the participant's participation for the full duration of the study, or is not in the best interest of the participant to participate, in the opinion of the treating investigator
- Has a known psychiatric or substance abuse disorder that would interfere with the participant's ability to cooperate with the requirements of the study
- Has had an allogenic tissue/solid organ transplant
Trial locations and contacts
109 sites in 22 countries.
109 sites in 22 countries
United States11 sites
University Cancer & Blood Center, LLC ( Site 1521)
Athens, Georgia, 30607
University of Chicago Medical Center-Medicine - Section of Hematology/Oncology - Gastrointestinal P
Chicago, Illinois, 60637
UT Southwestern Medical Center ( Site 1551)
Dallas, Texas, 75390
The West Clinic, PLLC dba West Cancer Center ( Site 1576)
Germantown, Tennessee, 38138
Vanderbilt University Medical Center-Vanderbilt-Ingram Cancer Center ( Site 1509)
Nashville, Tennessee, 37232
Icahn School of Medicine at Mount Sinai ( Site 1528)
New York, New York, 10029
Hematology Oncology Associates of Rockland ( Site 1525)
Nyack, New York, 10960
Mid Florida Cancer Center ( Site 1519)
Orange City, Florida, 32763
UPMC Hillman Cancer Center ( Site 1516)
Pittsburgh, Pennsylvania, 15232
Northwest Medical Specialties, PLLC ( Site 1546)
Tacoma, Washington, 98405
Baylor Scott & White Medical Center - Temple-Division of Hematology/Oncology ( Site 1549)
Temple, Texas, 76508
Spain8 sites
Hospital Universitari Vall d'Hebron ( Site 1201)
Barcelona, Catalonia, 08035
HOSPITAL GENERAL UNIVERSITARIO GREGORIO MARAÑON ( Site 1206)
Madrid, Madrid, Comunidad de, 28007
Hospital Clinico San Carlos-Oncology Department ( Site 1204)
Madrid, 28040
H.R.U Malaga - Hospital General ( Site 1207)
Málaga, Malaga, 29010
Hospital Universitario Central de Asturias-Medical Oncology ( Site 1203)
Oviedo, Principality of Asturias, 33011
COMPLEJO HOSPITALARIO DE NAVARRA-oncologia médica ( Site 1210)
Pamplona, Navarre, 31009
Hospital Universitario Marqués de Valdecilla ( Site 1202)
Santander, Cantabria, 39008
Fundación Instituto Valenciano de Oncología ( Site 1209)
Valencia, Valenciana, Comunitat, 46009
Colombia7 sites
Clinica de la Costa S.A.S. ( Site 1608)
Barranquilla, Atlántico, 080020
Clinica Colsanitas S.A, Sede Clínica Universitaria Colombia ( Site 1611)
Bogotá, Bogota D.C., 111321
Mediservis del Tolima IPS S.A.S ( Site 1609)
Ibague, Tolima Department, 730006
Instituto de Cancerología ( Site 1610)
Medellín, Antioquia, 050025
Fundación Colombiana de Cancerología Clínica Vida ( Site 1606)
Medellín, Antioquia, 050030
Oncomédica S.A.S ( Site 1602)
Montería, Departamento de Córdoba, 230002
Sociedad De Oncologia Y Hematologia Del Cesar-Oncology ( Site 1601)
Valledupar, Cesar Department, 200001
Germany7 sites
Charité Universitaetsmedizin Berlin - Campus Mitte ( Site 0604)
Berlin, 10117
Universitaetsklinikum Carl Gustav Carus Dresden-Medical Dept I - Medical Oncology ( Site 0601)
Dresden, Saxony, 01307
Kliniken Essen-Mitte, Evangelische Huyssens-Stiftung ( Site 0611)
Essen, North Rhine-Westphalia, 45136
Asklepios Altona-Oncology ( Site 0602)
Hamburg, 22763
Otto-von-Guericke-Universität Magdeburg-Klinik für Gastroenterologie, Hepatologie und Infektiologie
Magdeburg, Saxony-Anhalt, 39120
Universitätsklinikum Marburg ( Site 0610)
Marburg, Hesse, 35043
Muenchen Klinik Neuperlach, Klinik fuer Haematologie und Onkologie ( Site 0612)
Munich, Bavaria, 81737
South Korea7 sites
Kyungpook National University Chilgok Hospital-Hematology/oncology ( Site 1103)
Daegu, Taegu-Kwangyokshi, 41404
Korea University Anam Hospital ( Site 1107)
Seoul, 02841
Seoul National University Hospital-Internal Medicine ( Site 1101)
Seoul, 03080
Severance Hospital, Yonsei University Health System-Medical oncology ( Site 1104)
Seoul, 03722
Asan Medical Center-Department of Oncology ( Site 1105)
Seoul, 05505
Samsung Medical Center-Division of Hematology/Oncology ( Site 1102)
Seoul, 06351
The Catholic Univ. of Korea Seoul St. Mary's Hospital-Medical Oncology ( Site 1106)
Seoul, 06591
France6 sites
Centre Georges François Leclerc ( Site 0506)
Dijon, Cote-d Or, 21079
Hopital Claude Huriez - CHU de Lille ( Site 0510)
Lille, Nord, 59037
Assistance Publique Hôpitaux de Marseille - Hôpital de la Ti-Service d'Hepato-Gastro-Enterologie et
Marseille, Bouches-du-Rhone, 13385
Hôpital Saint Antoine-Oncologie médicale ( Site 0508)
Paris, 75571
Centre Hospitalier Universitaire de Poitiers ( Site 0511)
Poitiers, Vienne, 86021
CHU Rangueil-Digestive oncology department ( Site 0502)
Toulouse, Haute-Garonne, 31059
Hungary6 sites
Semmelweis Egyetem-Belgyógyászati és Hematológiai Klinika ( Site 2002)
Budapest, 1088
Debreceni Egyetem Klinikai Kozpont-Onkológiai Klinika ( Site 2008)
Debrecen, 4032
Somogy Megyei Kaposi Mór Oktató Kórház-Oncology center ( Site 2010)
Kaposvár, Somogy County, 7400
Bacs-Kiskun Megyei Korhaz-Onkoradiologiai Kozpont ( Site 2005)
Kecskemét, Bács-Kiskun county, 6000
Pécsi Tudományegyetem Klinikai Központ-Onkoterápiás Intézet ( Site 2009)
Pécs, Baranya, 7624
Jász-Nagykun-Szolnok Megyei Hetényi Géza Kórház-Onkologiai Kozpont ( Site 2001)
Szolnok, Jász-Nagykun-Szolnok, 5000
Poland6 sites
Powiatowe Centrum Zdrowia ( Site 0911)
Brzeziny, Łódź Voivodeship, 95-060
Szpital Wojewódzki im. Mikoaja Kopernika w Koszalinie-Oddzial Dzienny Chemioterapii ( Site 0903)
Koszalin, West Pomeranian Voivodeship, 75-581
Mrukmed-Mrukmed ( Site 0901)
Rzeszów, Podkarpackie Voivodeship, 35-021
Luxmed Onkologia sp. z o. o. ( Site 0915)
Warsaw, Masovian Voivodeship, 01-748
Narodowy Instytut Onkologii im. Marii Sklodowskiej-Curie - P-Klinika Onkologii i Radioterapii ( Site
Warsaw, Masovian Voivodeship, 02-034
DOLNOSLASKIE CENTRUM ONKOLOGII PULMONOLOGII I HEMATOLOGII ( Site 0920)
Wroclaw, Lower Silesian Voivodeship, 53-413
Russia6 sites
Republican Clinical Oncology Dispensary-Chemotherapy #3 ( Site 1006)
Kazan', Tatarstan, Respublika, 420029
Fed State Budgetary Inst N.N. Blokhin Med Center of Oncology-Clinical Pharmacology and Chemotherapy
Moscow, Moscow, 115478
First Moscow State Medical University I.M. Sechenov-Interhospital Institution Health Management Cl
Moscow, Moscow, 119991
Rostov Cancer Research Institute ( Site 1014)
Rostov-on-Don, Rostov Oblast, 344037
Saint-Petersburg City Clinical Oncology Dispensary-Department of chemotherapy ( Site 1001)
Saint Petersburg, Leningradskaya Oblast', 198255
GBUZ SPb CRPCstmc(o) ( Site 1005)
Saint Petersburg, Sankt-Peterburg, 197758
Belgium5 sites
UZ Brussel ( Site 0105)
Brussels, Bruxelles-Capitale, Region de, 1090
Cliniques universitaires Saint-Luc-Medical Oncology ( Site 0104)
Brussels, Bruxelles-Capitale, Region de, 1200
UZ Leuven ( Site 0101)
Leuven, Vlaams-Brabant, 3000
AZ Delta vzw ( Site 0106)
Roeselare, West-Vlaanderen, 8800
Université Catholique de Louvain-Namur - Centre Hospitalier -Oncology ( Site 0102)
Yvoir, Namur, 5530
Guatemala5 sites
CELAN,S.A ( Site 2202)
Guatemala City, 01010
INTEGRA Cancer Institute-Oncology ( Site 2201)
Guatemala City, 01010
MEDI-K CAYALA ( Site 2205)
Guatemala City, 01016
Centro Regional de Sub Especialidades Médicas SA ( Site 2204)
Quetzaltenango, 09001
Centro Medico Integral De Cancerología (CEMIC) ( Site 2203)
Quetzaltenango, 09002
Turkey (Türkiye)5 sites
Baskent University Dr. Turgut Noyan Research and Training Center ( Site 1303)
Adana, 01250
Hacettepe Universitesi-oncology hospital ( Site 1301)
Ankara, 06230
Ankara City Hospital-Medical Oncology ( Site 1306)
Ankara, 06800
Istanbul Universitesi Cerrahpasa-Medical Oncology ( Site 1302)
Istanbul, 34668
TC Saglik Bakanligi Goztepe Prof. Dr. Suleyman Yalcin Sehir Hastanesi-oncology ( Site 1305)
Istanbul, 34722
Denmark4 sites
Aalborg Universitetshospital, Syd ( Site 1903)
Aalborg, North Denmark, 9000
Rigshospitalet ( Site 1904)
Copenhagen, Capital Region, 2100
Regionshospitalet Gødstrup ( Site 1901)
Herning, Central Jutland, 7400
Odense Universitetshospital ( Site 1902)
Odense, Region Syddanmark, 5000
Greece4 sites
Alexandra General Hospital of Athens-ONCOLOGY DEPT. ( Site 2704)
Athens, Attica, 115 28
Evgenidion Hospital ( Site 2702)
Athens, Attica, 115 28
University General Hospital of Heraklion-Internal Medicine-Oncology ( Site 2703)
Heraklion, Irakleio, 715 00
European Interbalkan Medical Center-Oncology Department ( Site 2701)
Thessaloniki, 57001
Romania4 sites
Spitalul de Oncologie Monza Oncologie Medicala ( Site 2601)
Bucharest, Bucharest, 013812
Fundeni Clinical Institute-Medical Oncology ( Site 2603)
Bucharest, Bucharest, 022328
Cardiomed SRL Cluj-Napoca ( Site 2602)
Cluj-Napoca, Cluj, 400015
Centrul de Oncologie "Sfântul Nectarie"-Medical Oncology ( Site 2604)
Craiova, Dolj, 200542
United Kingdom4 sites
Velindre Cancer Centre-Research and Development ( Site 1415)
Cardiff, CF14 2TL
University Hospital Coventry & Warwickshire ( Site 1406)
Coventry, CV2 2DX
Beatson West of Scotland Cancer Centre-Clinical Trials Unit ( Site 1401)
Glasgow, Glasgow City, G12 0YN
UCLH-Cancer Clinical Trials Unit ( Site 1402)
London-Camden, London, City of, NW1 2PG
Canada3 sites
The Moncton Hospital-Oncology ( Site 0307)
Moncton, New Brunswick, E1C 6Z8
McGill University Health Centre-CIM - Oncology ( Site 0306)
Montreal, Quebec, H4A 3J1
Sunnybrook Research Institute - Odette Cancer Centre ( Site 0316)
Toronto, Ontario, M4N 3M5
Italy3 sites
Fondazione IRCCS Istituto Nazionale dei Tumori-Struttura Complessa Oncologia Medica 1 ( Site 0802)
Milan, Lombardy, 20133
Istituto Nazionale Tumori IRCCS Fondazione Pascale-Department of Abdominal Oncology ( Site 0803)
Naples, 80131
Istituto Oncologico Veneto IRCCS ( Site 0804)
Padova, 35128
Lithuania3 sites
Hospital of Lithuanian University of Health Sciences Kauno klinikos ( Site 2402)
Kaunas, Kaunas County, 50161
National Cancer Institute ( Site 2401)
Vilnius, Vilniaus Miestas, 08660
VILNIUS UNIVERSITY HOSPITAL SANTAROS KLINIKOS ( Site 2403)
Vilnius, 08460
Costa Rica2 sites
CIMCA-Hemato-Oncology ( Site 2101)
San José, Provincia de San José, 1000
Hospital Metropolitano - Sede Lindora-Metropolitano Research Institute Sede Lindora ( Site 2102)
Santa Ana, Provincia de San José, 10903
Estonia2 sites
North Estonia Medical Centre Foundation-Chemotherapy ( Site 2301)
Tallinn, Harju, 13419
Tartu University Hospital ( Site 2302)
Tartu, Tartu, 50406
Netherlands1 site
Nederlands Kanker Instituut - Antoni van Leeuwenhoek (NKI-AVL) ( Site 2901)
Amsterdam, North Holland, 1066CX
About this study
Official title: A Phase 2, Multicenter, Multi Arm, Study to Evaluate MK-1308A (Co-formulated Quavonlimab (MK-1308)/Pembrolizumab) Versus Other Treatments in Participants With Microsatellite Instability-High (MSI-H) or Mismatch Repair Deficient (dMMR) Stage IV Colorectal Cancer: (MK-1308A-008)
The purpose of this study is to assess the efficacy and safety of co-formulated pembrolizumab/quavonlimab versus other treatments in participants with MSI-H or dMMR Metastatic Stage IV Colorectal Cancer.
- Conditions
- Colorectal Cancer
- Being tested
- Pembrolizumab, Pembrolizumab/Quavonlimab, Pembrolizumab/Favezelimab, Pembrolizumab/Vibostolimab, MK-4830
- Keywords
- Programmed Cell Death-1 (PD1, PD-1), Programmed Death-Ligand 1 (PDL1, PD-L1)
- Medical subject headings
- Colorectal Neoplasms, Parkinson Disease 4, Autosomal Dominant Lewy Body
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
PembrolizumabBiological
Also called MK-3475, Keytruda®
400 mg or 200 mg pembrolizumab administered via IV infusion.
Pembrolizumab/QuavonlimabBiological
Also called MK-1308A
Co-formulated pembrolizumab/quavonlimab (400 mg/25 mg) fixed-dose combination (FDC) administered via IV infusion.
Pembrolizumab/FavezelimabBiological
Also called MK-4280A
Co-formulated pembrolizumab/favezelimab (200 mg/800 mg) FDC administered via IV infusion
Pembrolizumab/VibostolimabBiological
Also called MK-7684A
Co-formulated pembrolizumab/vibostolimab (200 mg/200 mg) FDC administered via IV infusion
MK-4830Biological
800 mg MK-4830 administered via IV infusion
| Study group | Role | What they receive |
|---|---|---|
| Cohort A - Pembrolizumab/Quavonlimab | Experimental | Participants in Cohort A receive co-formulated pembrolizumab/quavonlimab (400 mg/25 mg) every 6 weeks (Q6W) for up to approximately 2 years. Receives: Biological: Pembrolizumab/Quavonlimab |
| Cohort A - Pembrolizumab | Active comparator | Participants in Cohort A receive pembrolizumab 400 mg intravenously (IV) Q6W for up to approximately 2 years. Receives: Biological: Pembrolizumab |
| Cohort B - Pembrolizumab/Quavonlimab | Experimental | Participants received co-formulated pembrolizumab/quavonlimab (400 mg/25 mg) Q6W for up to approximately 2 years. Receives: Biological: Pembrolizumab/Quavonlimab |
| Cohort B - Pembrolizumab Plus MK-4830 | Experimental | Participants receive pembrolizumab 200 mg plus MK-4830 800 mg Q3W for up to approximately 2 years. Receives: Biological: Pembrolizumab; Biological: MK-4830 |
| Cohort B - Pembrolizumab/Favezelimab | Experimental | Participants receive co-formulated pembrolizumab/favezelimab (200 mg/800 mg) every 3 weeks (Q3W) for up to approximately 2 years. Receives: Biological: Pembrolizumab/Favezelimab |
| Cohort B - Pembrolizumab/Vibostolimab | Experimental | Participants receive co-formulated pembrolizumab/vibostolimab (200 mg/200 mg) Q3W for up to approximately 2 years. Receives: Biological: Pembrolizumab/Vibostolimab |
| Cohort B - Pembrolizumab | Active comparator | Participants in Cohort B receive pembrolizumab 400 mg IV Q6W for up to approximately 2 years. Receives: Biological: Pembrolizumab |
What is being measured
The primary outcome is the main question the study is designed to answer.
Objective Response Rate (ORR) Per Response Evaluation Criteria in Solid Tumors Version 1.1 (RECIST 1.1) as Assessed by Blinded Independent Central Review (BICR)
ORR was defined as the percentage of participants who have a Complete Response (CR: disappearance of all target lesions) or a Partial Response (PR: at least a 30% decrease in the sum of diameters of target lesions) per RECIST 1.1. ORR as assessed by BICR is presented.
Measured: Up to approximately 46 months
Secondary outcomes (8)
Duration of Response (DOR) Per RECIST 1.1 as Assessed by BICR
DOR was defined as the time from the first documented evidence of a CR (disappearance of all target lesions) or a PR (at least a 30% decrease in the sum of diameters of target lesions) per RECIST 1.1 until Progressive Disease (PD) or death due to any cause, whichever occurs first, in participants demonstrating a CR or PR. Per RECIST 1.1, PD was defined as at least a 20% increase in the sum of diameters of target lesions. In addition to the relative increase of 20%, the sum must also demonstrate an absolute increase of at least 5 mm. The appearance of one or more new lesions was also considered PD. DOR as assessed by BICR is presented.
Measured: Up to approximately 46 months
Progression-Free Survival (PFS) Per RECIST 1.1 as Assessed by BICR
PFS was defined as the time from randomization to the first documented PD per RECIST 1.1 or death from any cause, whichever occurs first. Per RECIST 1.1, PD was defined as at least a 20% increase in the sum of diameters of target lesions. In addition to the relative increase of 20%, the sum must also demonstrate an absolute increase of at least 5 mm. The appearance of one or more new lesions was also considered PD. PFS as assessed by BICR is presented.
Measured: Up to approximately 46 months
PFS Per RECIST 1.1 as Assessed by Investigator
PFS was defined as the time from randomization to the first documented PD per RECIST 1.1 or death from any cause, whichever occurs first. Per RECIST 1.1, PD is defined as at least a 20% increase in the sum of diameters of target lesions. In addition to the relative increase of 20%, the sum must also demonstrate an absolute increase of at least 5 mm. The appearance of one or more new lesions is also considered PD. PFS as assessed by investigator is presented.
Measured: Up to approximately 46 months
ORR Per RECIST 1.1 as Assessed by Investigator
ORR was defined as the percentage of participants who had a CR (disappearance of all target lesions) or a PR (at least a 30% decrease in the sum of diameters of target lesions) per RECIST 1.1. ORR as assessed by investigator is be presented.
Measured: Up to approximately 46 months
DOR Per RECIST 1.1 as Assessed by Investigator
DOR was defined as the time from the first documented evidence of a CR (disappearance of all target lesions) or a PR (at least a 30% decrease in the sum of diameters of target lesions) per RECIST 1.1 until PD or death due to any cause, whichever occurs first, in participants demonstrating a CR or PR. Per RECIST 1.1, PD was defined as at least a 20% increase in the sum of diameters of target lesions. In addition to the relative increase of 20%, the sum must also demonstrate an absolute increase of at least 5 mm. The appearance of one or more new lesions is also considered PD. DOR as assessed by investigator is presented.
Measured: Up to approximately 46 months
Overall Survival (OS)
OS was defined as the time from randomization (or first dose) to death due to any cause. OS is presented.
Measured: Up to approximately 46 months
Number of Participants Who Experienced an Adverse Event (AE)
An AE was any untoward medical occurrence in a participant, temporally associated with the use of study treatment, whether or not considered related to the study intervention. The number of participants with an AE is presented.
Measured: Up to approximately 60 months
Number of Participants Discontinuing Study Treatment Due to an AE
An AE was any untoward medical occurrence in a participant, temporally associated with the use of study treatment, whether or not considered related to the study intervention. The number of participants that discontinue study treatment due to an AE is presented.
Measured: Up to approximately 60 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted20 May 2021
- Study start25 Jun 2021
- Primary completion21 May 2025
- Study completion6 Aug 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Colorectal CancerStudies of the same condition, open and under way.
- More trials run by Merck Sharp & Dohme LLCThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 2
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 302 participants (actual)
Sponsor and investigators
- Lead sponsor
- Merck Sharp & Dohme LLC
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Medical Director, Study director, Merck Sharp & Dohme LLC
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04895722
- Sponsor's protocol ID
- 1308A-008
- Other IDs
- MK-1308A-008, 2022-502100-70-00, KEYSTEP-008, U1111-1283-2434, 2020-005114-18
- Status last verified
- Jun 2026
- First submitted
- 18 May 2021
- Last updated
- 2 Jul 2026
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- Yes: https://trialstransparency.msdclinicaltrials.com/pdf/ProcedureAccessClinicalTrialData.pdf
Publications
Andre T, Pietrantonio F, Avallone A, Gumus M, Wyrwicz L, Kim JG, Yalcin S, Kwiatkowski M, Lonardi S, Zolnierek J, Odeleye-Ajakaye A, Leconte P, Fogelman D, Kim TW. KEYSTEP-008: phase II trial of pembrolizumab-based combination in MSI-H/dMMR metastatic colorectal cancer. Future Oncol. 2023 Dec;19(37):2445-2452. doi: 10.2217/fon-2022-1105. Epub 2023 Sep 13.
PubMed 37701986