Colorectal CancerPhase 3NCT05600309
A Study of Coformulated Favezelimab/Pembrolizumab (MK-4280A) Versus Standard of Care in Subjects With Previously Treated Metastatic PD-L1 Positive Colorectal Cancer (MK-4280A-007)-China Extension Study
A Phase 3 study testing favezelimab/pembrolizumab, regorafenib and TAS-102 in people with Colorectal Cancer, run by Merck Sharp & Dohme LLC at 24 sites in China.
Trial summary
The purpose of this China extension study is to assess the safety and efficacy of coformulated favezelimab/pembrolizumab (MK-4280A) in adult Chinese participants with metastatic 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?
- favezelimab/pembrolizumab, regorafenib and TAS-102
- Type of treatment
- Pill or oral medicine, Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 94 participants
- Where
- 24 sitesChina
- Study dates
- 14 Jun 2022to 21 Feb 2025
- Phase
- Phase 3
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
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 colorectal adenocarcinoma that is metastatic and unresectable.
- Has measurable disease per RECIST 1.1 as assessed by the local site investigator.
- Has been previously treated for the disease and radiographically progressed on or after or could not tolerate standard treatment.
- Submits an archival (≤ 5 years) or newly obtained tumor tissue sample or newly obtained tumor tissue sample that has not been previously irradiated.
- Has an Eastern Cooperative Oncology Group Performance Score (ECOG PS) of 0 to 1 within 10 days prior to first dose of study intervention.
- Has a life expectancy of at least 3 months, based on the investigator assessment.
- Has the ability to swallow and retain oral medication and not have any clinically significant gastrointestinal abnormalities that might alter absorption.
- Has adequate organ function.
Who cannot join
- Has previously been found to have deficient mismatch repair/microsatellite instability-high (dMMR/MSI-H) tumor status.
- Has known active central nervous system (CNS) metastases and/or carcinomatous meningitis or leptomeningeal disease.
- Has a history of acute or chronic pancreatitis.
- Has neuromuscular disorders associated with an elevated creatine kinase (eg, inflammatory myopathies, muscular dystrophy, amyotrophic lateral sclerosis, spinal muscular atrophy)
- Has clinically significant cardiovascular disease within 12 months from first dose of study intervention, including New York Heart Association Class III or IV congestive heart failure, unstable angina, myocardial infarction, cerebral vascular accident, or cardiac arrhythmia associated with hemodynamic instability.
- Has urine protein greater than or equal to 1g/24h.
Show all 21Show fewer
- A woman of childbearing potential who has a positive urine/serum pregnancy test within 24/72 hours prior to the first dose of study intervention.
- Has received prior therapy with an anti-programmed cell death 1 (PD-1), anti-programmed death ligand 1 (PD-L1), or anti-programmed cell death ligand 2 (PD-L2), anti-lymphocyte activation gene 3 (LAG-3) antibody, with a tyrosine kinase inhibitor (TKI; eg, lenvatinib) other than rapidly accelerated fibrosarcoma (RAF) inhibitors (binimetinib is permitted if combined with a RAF inhibitor), or with an agent directed to another stimulatory or coinhibitory T-cell receptor (eg, cytotoxic T-lymphocyte-associated protein 4, OX-40, cluster of differentiation [CD] 137).
- Has previously received regorafenib or TAS-102.
- Has received prior systemic anticancer therapy including investigational agents within 28 days before randomization.
- Has received prior radiotherapy within 2 weeks of start of study intervention. Participants must have recovered from all radiation-related toxicities, not require corticosteroids, and not have had radiation pneumonitis. A 1-week washout is permitted for palliative radiation (≤2 weeks of radiotherapy) to non-CNS disease.
- Has received a live or live-attenuated vaccine within 30 days before the first dose of study intervention.
- Has a known additional malignancy that is progressing or has required active treatment within the past 3 years.
- Has severe hypersensitivity (≥Grade 3) to pembrolizumab and/or any of its excipients.
- Has an active autoimmune disease that has required systemic treatment in past 2 years.
- Has a history of (noninfectious) pneumonitis/interstitial lung disease that required steroids or has current pneumonitis/interstitial lung disease.
- Has an active infection requiring systemic therapy (eg, tuberculosis, known viral or bacterial infections, etc.).
- Has a known history of human immunodeficiency virus (HIV) infection.
- Has known history of Hepatitis B or known active Hepatitis C virus infection.
- 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 had an allogenic tissue/solid organ transplant.
Trial locations and contacts
24 sites in 1 country.
24 sites in 1 country
China24 sites
Jilin Cancer Hospital ( Site 1163)
Changchun, Jilin, 130012
Xiangya Hospital Central South University ( Site 1171)
Changsha, Hunan, 410008
Hunan Cancer Hospital ( Site 1174)
Changsha, Hunan, 410013
The Third Xiangya Hospital of Central South University ( Site 1175)
Changsha, Hunan, 410013
Changzhou Cancer Hospital-Department of Oncology ( Site 1183)
Changzhou, Jiangsu, 213000
West China Hospital Sichuan University ( Site 1172)
Chengdu, Sichuan, 332001
Chongqing Cancer Hospital ( Site 1151)
Chongqing, Chongqing Municipality, 400030
Fujian Province Cancer Hospital ( Site 1178)
Fuzhou, Fujian, 350014
Sun Yat-Sen University Cancer Center ( Site 1150)
Guangzhou, Guangdong, 510060
Southern Medical University Nanfang Hospital ( Site 1154)
Guangzhou, Guangdong, 510515
The Sixth Affiliated Hospital of Sun Yat-sen University ( Site 1159)
Guangzhou, Guangdong, 510655
Hainan General Hospital ( Site 1177)
Haikou, Hainan, 570311
Zhejiang Cancer Hospital ( Site 1180)
Hangzhou, Zhejiang, 310005
Sir Run Run Shaw Hospital-Medical Oncology ( Site 1173)
Hangzhou, Zhejiang, 310018
The Second Affiliated Hospital of Anhui Medical University ( Site 1179)
Hefei, Anhui, 230601
Jinan Central Hospital ( Site 1167)
Jinan, Shandong, 250000
Yunnan Province Cancer Hospital-Colorectal surgery ( Site 1169)
Kunming, Yunnan, 650106
Guangxi Medical University Affiliated Tumor Hospital ( Site 1158)
Nanning, Guangxi, 531021
Shanghai Tenth People's Hospital ( Site 1170)
Shanghai, Shanghai Municipality, 200072
Fudan University Shanghai Cancer Center ( Site 1176)
Shanghai, Shanghai Municipality, 201321
Tianjin Medical University Cancer Institute and Hospital ( Site 1161)
Tianjin, Tianjin Municipality, 300060
Wuhan Union Hospital Cancer Center ( Site 1162)
Wuhan, Hubei, 430022
Hubei Cancer Hospital ( Site 1152)
Wuhan, Hubei, 430079
Affiliated Hospital of Jiangnan University(Wuxi Fourth People's Hospital ) ( Site 1185)
Wuxi, Jiangsu, 214122
About this study
Official title: A Phase 3 Study of MK-4280A (Coformulated Favezelimab [MK-4280] Plus Pembrolizumab [MK-3475]) Versus Standard of Care in Previously Treated Metastatic PD-L1 Positive Colorectal Cancer (KEYFORM-007)
The purpose of this China extension study is to assess the safety and efficacy of coformulated favezelimab/pembrolizumab (MK-4280A) in adult Chinese participants with metastatic colorectal cancer. The study will also compare MK-4280A with the standard of care treatment of regorafenib and TAS-102 (trifluridine and tipiracil).
The primary study hypothesis is that coformulated favezelimab/pembrolizumab (MK-4280A) is superior to standard of care with respect to overall survival.
Read the detailed description
The China extension study will include participants previously enrolled in China in the global study for MK-4280A-007 (NCT05064059) plus those enrolled during the China extension enrollment period. A total of approximately 94 Chinese participants will be enrolled.
As of Amendment 3 of the supplemental statistical analysis plan, patient reported outcomes will no longer be secondary outcome measures of the study.
- Conditions
- Colorectal Cancer
- Being tested
- favezelimab/pembrolizumab, regorafenib, TAS-102
- Keywords
- Programmed Cell Death-1 (PD1, PD-1),, Programmed Cell Death Receptor Ligand 1 (PDL1, PD-L1), Programmed Cell Death Receptor Ligand 2 (PDL2, PD-L2)
- 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.
favezelimab/pembrolizumabBiological
Also called MK-4280A
Coformulated favezelimab/pembrolizumab (800 mg/200 mg), IV infusion
regorafenibDrug
Also called STIVARGA®, REGONIX®
Oral
TAS-102Drug
Also called LONSURF®
Oral
| Study group | Role | What they receive |
|---|---|---|
| Favezelimab/Pembrolizumab | Experimental | Participants will receive coformulated favezelimab/pembrolizumab (800 mg/200 mg) intravenously (IV) on Day 1, then every 3 weeks (Q3W), for up to 35 infusions. Receives: Biological: favezelimab/pembrolizumab |
| Standard of Care (Regorafenib or TAS-102) | Active comparator | At the Investigator's choice, participants will receive 160 mg regorafenib orally daily on Days 1-12 of each 28-day cycle or 35 mg/m^2 TAS-102 orally twice daily on Days 1-5 and Days 8-12 of each 28-day cycle. Receives: Drug: regorafenib; Drug: TAS-102 |
What is being measured
The primary outcome is the main question the study is designed to answer.
Overall Survival (OS)
OS was defined as the time from randomization to death due to any cause.
Measured: Up to approximately 26 months
Secondary outcomes (5)
Progression-Free Survival (PFS) According Per Response Evaluation Criteria in Solid Tumors Version 1.1 (RECIST 1.1) as Assessed by Blinded Independent Central Review (BICR)
PFS was defined as the time from randomization to the first documented disease progression per RECIST 1.1 by BICR or death due to any cause, whichever occurred first. Per RECIST 1.1, PD was defined as ≥20% increase in the sum of diameters of target lesions. In addition to the relative increase of 20%, the sum must also have demonstrated an absolute increase of ≥5 mm. The appearance of one or more new lesions was also considered PD.
Measured: Up to approximately 26 months
Objective Response Rate (ORR) Per RECIST 1.1 as Assessed by BICR
ORR was defined as the percentage of participants who achieved a confirmed complete response (CR: Disappearance of all target lesions) or partial response (PR: At least a 30% decrease in the sum of diameters of target lesion) per RECIST 1.1 as assessed by BICR
Measured: Up to approximately 26 months
Duration of Response (DOR) Per RECIST 1.1 as Assessed by BICR
For participants who demonstrate confirmed CR (disappearance of all target lesions) or PR (At least a 30% decrease in the sum of diameters of target lesions), duration of response was defined as the time from the first documented evidence of CR or PR until progressive disease (PD) or death due to any cause. DOR for participants who had not progressed or died at the time of analysis was to be censored at the date of their last tumor assessment. Per RECIST 1.1, PD was defined as at least a 20% increase in the sum of diameters of target lesions as well as an absolute increase of at least a 5 mm in the sum of diameters. The appearance of one or more new lesions was also considered PD. DOR assessments were based on blinded central imaging review with confirmation.
Measured: Up to approximately 26 months
Number of Participants Who Experienced at Least One Adverse Event (AE)
An AE was any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention.
Measured: Up to approximately 20 months
Number of Participants Who Discontinued Study Treatment Due to an AE
An AE was any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. The number of participants who discontinue study treatment due to an AE is presented.
Measured: Up to approximately 17 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted31 Oct 2022
- Study start14 Jun 2022
- Primary completion15 Aug 2024
- Study completion21 Feb 2025
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.
- 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 3
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 94 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
- NCT05600309
- Sponsor's protocol ID
- 4280A-007 China Extension
- Other IDs
- MK-4280A-007 China Extension, jRCT2031210482
- Status last verified
- Nov 2025
- First submitted
- 26 Oct 2022
- Last updated
- 26 Nov 2025
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- Yes: https://trialstransparency.msdclinicaltrials.com/pdf/ProcedureAccessClinicalTrialData.pdf
Study at a glance
From the registry record, last updated by the sponsor on 26 Nov 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Phase 3 Study of MK-4280A (Coformulated Favezelimab [MK-4280] Plus Pembrolizumab [MK-3475]) Versus Standard of Care in Previously Treated Metastatic PD-L1 Positive Colorectal Cancer (KEYFORM-007)
- ClinicalTrials.gov ID
- NCT05600309
- Acronym / sponsor ID
- 4280A-007 China Extension
- Conditions
- Colorectal Cancer
- Keywords
- Programmed Cell Death-1 (PD1, PD-1),, Programmed Cell Death Receptor Ligand 1 (PDL1, PD-L1), Programmed Cell Death Receptor Ligand 2 (PDL2, PD-L2)
- Phase
- Phase 3
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 94 participants (actual)
- Lead sponsor
- Merck Sharp & Dohme LLCIndustry (pharma, biotech, devices)
- Study start
- 14 Jun 2022 (actual)
- Primary completion
- 15 Aug 2024 (actual)
- Study completion
- 21 Feb 2025 (actual)
- First posted
- 31 Oct 2022 (actual)
- Results
- Posted 17 Sep 2025
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The purpose of this China extension study is to assess the safety and efficacy of coformulated favezelimab/pembrolizumab (MK-4280A) in adult Chinese participants with metastatic colorectal cancer. The study will also compare MK-4280A with the standard of care treatment of regorafenib and TAS-102 (trifluridine and tipiracil).
The primary study hypothesis is that coformulated favezelimab/pembrolizumab (MK-4280A) is superior to standard of care with respect to overall survival.
Detailed description
The China extension study will include participants previously enrolled in China in the global study for MK-4280A-007 (NCT05064059) plus those enrolled during the China extension enrollment period. A total of approximately 94 Chinese participants will be enrolled.
As of Amendment 3 of the supplemental statistical analysis plan, patient reported outcomes will no longer be secondary outcome measures of the study.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Favezelimab/Pembrolizumab | Experimental | Biological: favezelimab/pembrolizumabParticipants will receive coformulated favezelimab/pembrolizumab (800 mg/200 mg) intravenously (IV) on Day 1, then every 3 weeks (Q3W), for up to 35 infusions. |
| Standard of Care (Regorafenib or TAS-102) | Active comparator | Drug: regorafenib, Drug: TAS-102At the Investigator's choice, participants will receive 160 mg regorafenib orally daily on Days 1-12 of each 28-day cycle or 35 mg/m^2 TAS-102 orally twice daily on Days 1-5 and Days 8-12 of each 28-day cycle. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (8 listed)
- Has a histologically confirmed colorectal adenocarcinoma that is metastatic and unresectable.
- Has measurable disease per RECIST 1.1 as assessed by the local site investigator.
- Has been previously treated for the disease and radiographically progressed on or after or could not tolerate standard treatment.
- Submits an archival (≤ 5 years) or newly obtained tumor tissue sample or newly obtained tumor tissue sample that has not been previously irradiated.
- Has an Eastern Cooperative Oncology Group Performance Score (ECOG PS) of 0 to 1 within 10 days prior to first dose of study intervention.
Key exclusion criteria (21 listed)
- Has previously been found to have deficient mismatch repair/microsatellite instability-high (dMMR/MSI-H) tumor status.
- Has known active central nervous system (CNS) metastases and/or carcinomatous meningitis or leptomeningeal disease.
- Has a history of acute or chronic pancreatitis.
- Has neuromuscular disorders associated with an elevated creatine kinase (eg, inflammatory myopathies, muscular dystrophy, amyotrophic lateral sclerosis, spinal muscular atrophy)
- Has clinically significant cardiovascular disease within 12 months from first dose of study intervention, including New York Heart Association Class III or IV congestive heart failure, unstable angina, myocardial infarction, cerebral vascular accident, or cardiac arrhythmia associated with hemodynamic instability.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| favezelimab/pembrolizumabAlso: MK-4280ACoformulated favezelimab/pembrolizumab (800 mg/200 mg), IV infusion | Biological | Favezelimab/Pembrolizumab |
| regorafenibAlso: STIVARGA®, REGONIX®Oral | Drug | Standard of Care (Regorafenib or TAS-102) |
| TAS-102Also: LONSURF®Oral | Drug | Standard of Care (Regorafenib or TAS-102) |
Primary outcome
Overall Survival (OS)
Time frame: Up to approximately 26 months
OS was defined as the time from randomization to death due to any cause.
5 secondary outcomes
Progression-Free Survival (PFS) According Per Response Evaluation Criteria in Solid Tumors Version 1.1 (RECIST 1.1) as Assessed by Blinded Independent Central Review (BICR)
Time frame: Up to approximately 26 months
Objective Response Rate (ORR) Per RECIST 1.1 as Assessed by BICR
Time frame: Up to approximately 26 months
Duration of Response (DOR) Per RECIST 1.1 as Assessed by BICR
Time frame: Up to approximately 26 months
Number of Participants Who Experienced at Least One Adverse Event (AE)
Time frame: Up to approximately 20 months
Number of Participants Who Discontinued Study Treatment Due to an AE
Time frame: Up to approximately 17 months
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 26 Nov 2025.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- Merck Clinical Trials InformationLink provided by the sponsor.
- Plain Language SummaryLink provided by the sponsor.
- Individual participant dataSharing planned: Yes. https://trialstransparency.msdclinicaltrials.com/pdf/ProcedureAccessClinicalTrialData.pdf
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Medical Director study director
Merck Sharp & Dohme LLC
24 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 3 study testing favezelimab/pembrolizumab, regorafenib and TAS-102 in people with Colorectal Cancer, run by Merck Sharp & Dohme LLC at 24 sites in China.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 8 inclusion and 21 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 26 Nov 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 24 sites in China. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
Yes. Results are posted in the registry (first posted 17 Sep 2025). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Overall Survival (OS) (time frame: Up to approximately 26 months). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 26 Nov 2025.