A Phase 1/2 interventional study of Patritumab deruxtecan in Gastrointestinal Cancer, sponsored by Merck Sharp & Dohme LLC. Active, not recruiting at 62 sites in 15 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-10-02.
Sponsored by Merck Sharp & Dohme LLC · Phase 1/2, Interventional, and Treatment
Researchers want to learn if patritumab deruxtecan (MK-1022) can treat certain gastrointestinal (GI) cancers. The GI cancers being studied are advanced (the cancer has spread to other parts of the body). The goals of this study are to learn:
779 studies on the registry are indexed under Gastrointestinal Neoplasms; 231 are open to participants now.
This study's planned enrollment of 180 is above the median of 60 across 569 interventional studies indexed under Gastrointestinal Neoplasms.
Browse Gastrointestinal Neoplasms studies →Merck Sharp & Dohme LLC is the lead sponsor of 2,114 studies on the registry; 133 are open to participants now.
Of its 489 completed or terminated interventional studies of FDA-regulated products, 362 (74%) have results posted.
Counted across the registry records on this site, refreshed daily.
The main inclusion criteria include but are not limited to the following:
Has one of the following cancers:
Exclusion Criteria:
The main exclusion criteria include but are not limited to the following:
Participants receive patritumab deruxtecan intravenous (IV) infusion on Day 1 of each 21-day cycle (every 3 weeks) until disease progression, intolerable toxicity, or investigator decision.
Biological: Patritumab deruxtecan
Administered via intravenous (IV) infusion
Also known as: MK-1022, HER3-DXd, U3-1402
Number of Participants Experiencing Dose-Limiting Toxicity (DLT) (Dose-Escalation Phase)
DLT will be defined as any drug-related adverse event observed during the DLT evaluation period that results in a change to a given dose or a delay in initiating the next 21-day cycle. The number of participants in the dose-escalation phase who experience a DLT will be presented.
Time frame: Up to 21 days
Number of Participants with One or More Adverse Events (AEs)
An AE is defined as any unfavorable and unintended sign, symptom, disease, or worsening of preexisting condition temporally associated with study treatment and irrespective of causality to study treatment. The number of participants who experience an AE will be presented.
Time frame: Up to approximately 44 months
Number of Participants who Discontinue Study Intervention Due to an AE
An AE is defined as any unfavorable and unintended sign, symptom, disease, or worsening of preexisting condition temporally associated with study treatment and irrespective of causality to study treatment. The number of participants who discontinue study treatment due to an AE will be presented.
Time frame: Up to approximately 44 months
Objective Response Rate (ORR)
ORR is defined as the percentage of participants with Complete Response (CR: disappearance of all target lesions) or Partial Response (PR: at least a 30% decrease in the sum of diameters of target lesions) per Response Evaluation Criteria in Solid Tumors (RECIST) 1.1. The percentage of participants who experience CR or PR as assessed by Blinded Independent Central Review (BICR) will be presented.
Time frame: Up to approximately 44 months
Duration of Response (DOR)
For participants who demonstrate 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 lesions) per RECIST 1.1, DOR is defined as the time from first documented evidence of CR or PR until progressive disease (PD) or death. 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. DOR as assessed by BICR will be presented.
Time frame: Up to approximately 44 months
Progression Free Survival (PFS)
PFS is defined as the time from first day of study intervention to the first documented progressive disease (PD) or death due to any cause, whichever occurs first as assessed by BICR. Per RECIST 1.1, PD is defined as ≥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 ≥5 mm. The appearance of one or more new lesions is also considered PD. The appearance of one or more new lesions is also considered PD. PFS as assessed by BICR will be presented.
Time frame: Up to approximately 44 months
Overall Survival (OS)
OS is the length of time from when the participant starts treatment until death from any cause.
Time frame: Up to approximately 44 months
Maximum Plasma Concentration (Cmax) of Patritumab Deruxtecan
Blood samples collected at protocol specific time points will be used to determine the Cmax of patritumab deruxtecan.
Time frame: At designated time points (up to ~44 months)
Trough Concentration (Ctrough) of Patritumab Deruxtecan
Blood samples collected at protocol specific time points will be used to determine the Ctrough of patritumab deruxtecan.
Time frame: At designated time points (up to ~44 months)
Plan to share: Yes — https://trialstransparency.msdclinicaltrials.com/pdf/ProcedureAccessClinicalTrialData.pdf
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is active, not recruiting, as verified in Sep 2026. You cannot join it, but the record below documents what was studied.
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Merck Sharp & Dohme LLC