A Study of ASP2138 for Stomach, GEJ, or Pancreatic Cancer
This study is testing a drug called ASP2138, alone or with other cancer treatments like Pembrolizumab, Oxaliplatin, Leucovorin, and Fluorouracil. It's for adults with stomach cancer, gastroesophageal junction (GEJ) cancer (where the food pipe meets the stomach), or pancreatic cancer. ASP2138 is designed to target a protein called CLDN18.2, found on some tumor cells, and help your immune system attack the cancer. The main goal of this study is to understand the safety of ASP2138 and identify any side effects. We are looking for about 398 participants. The current recruitment status is unclear.
- Study design
- This is an interventional study with a planned enrollment of 398 participants. It will test ASP2138 by itself or in combination with other standard cancer treatments.
- What's involved
- Not specified in the trial record.
- Compensation
- Not stated in the trial record.
- Follow-up
- Participants will be monitored for adverse events for up to 27 months after treatment.
AI-generated from the public study record. Only the study team can confirm whether you're eligible — confirm details with them before making decisions.
NCT05365581
A Study of ASP2138 Given by Itself or Given With Other Cancer Treatments in Adults With Stomach Cancer, Gastroesophageal Junction Cancer, or Pancreatic Cancer
Recruiting
PHASE1Ages 18+InterventionalTreatmentAstellas Pharma Global Development, Inc.
~398 participants
Updated 2026-07-15 on ClinicalTrials.gov
What's tested:ASP2138PembrolizumabOxaliplatinLeucovorinFluorouracilRamucirumab
At a glance
Recruiting sites
42 of 46 listed sites are recruiting right now
RecruitingSuspended, closed, or not yet open
What they're measuring
Incidence of Dose Limiting Toxicities (DLTs) (Phase 1 Dose Escalation)
Measured over Up to 28 days
+7 more outcomes measured
Conditions
Where it's being run
46 sites across 26 statesFrance5
Spain5
Italy4
Seoul4
New York3
California2
North Carolina2
Osaka2
Study leadership
- Senior Director · STUDY_DIRECTOR · Astellas Pharma Global Development, Inc.
Who to contact
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Do you actually qualify for this trial?
Add a private profile and we'll compare every criterion below against your situation — and tell you which ones are met, uncertain, or excluding.
Eligibility criteria
Inclusion
Participant is considered an adult according to local regulation at the time of signing the informed consent form (ICF).
Female participant is not pregnant, confirmed by serum pregnancy test \&vmedical evaluation by interview \& at least 1 of the following conditions apply:
Not a woman of childbearing potential (WOCBP)
WOCBP who agrees to follow the contraceptive guidance from the time of informed consent through at least 6 months after final study intervention administration.
Female participant must agree not to breastfeed starting at screening \& throughout the study period \& for 6 months after the final study intervention administration.
Female participant must not donate ova starting at screening \& throughout the study period \& for 6 months after the final study intervention administration.
Male participant with female partner(s) of childbearing potential (including breastfeeding partner) must agree to use contraception throughout the treatment period \& for 6 months after the final study intervention administration.
Male participant must not donate sperm during the treatment period \& for 6 months after the final study intervention administration.
Male participant with pregnant or breastfeeding partner(s) must agree to remain abstinent or use a condom for the duration of the pregnancy or time partner is breastfeeding throughout the study period \& for 6 months after the final study intervention administration.
Participant's tumor sample is positive for claudin (CLDN)18.2 expression by central immunohistochemistry (IHC) testing.
Participant has radiographically-confirmed, locally advanced, unresectable or metastatic disease within 28 days prior to the first dose of study intervention.
Participant has at least 1 measurable disease according to Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 within 28 days prior to the first dose of study intervention. Lesions situated in a previously irradiated area are considered measurable if progression has been demonstrated in such lesions.
Participant has QT interval by Fredericia (QTcF) =\< 470 msec.
Participant agrees not to participate in another interventional study while receiving study Intervention in the present study.
Participant has Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1.
Participant has predicted life expectancy \>= 12 weeks.
Participant must meet all of criteria based on laboratory tests within 7 days prior to the first dose of study Intervention. In case of multiple laboratory data within this period, the most recent data should be used. If a participant has received a recent blood transfusion, the laboratory tests must be obtained \>= 1 week after any blood transfusion.
Participant has histologically confirmed metastatic, locally advanced unresectable gastric/gastroesophageal junction (GEJ) adenocarcinoma.
Escalation: Participant with gastric/GEJ adenocarcinoma who has progressed, is intolerant, has refused, or for whom there is no standard approved therapies that impart significant clinical benefit (no limit to the number of prior treatment regimens).
Unique to South Korea: Participant with gastric/GEJ adenocarcinoma who has refused standard approved therapies is not allowed.
Expansion: Participant with gastric/GEJ adenocarcinoma must have received no more than 3 prior lines of systemic chemotherapy treatment.
Unique to EU: Expansion: Participant with gastric/GEJ adenocarcinoma must have received at least first-line standard therapies in the metastatic setting, must have received ramucirumab treatment if eligible \& where ramucirumab is available, \& no more than 3 prior lines of systemic chemotherapy treatment.
Participant has histologically or cytologically confirmed metastatic pancreatic adenocarcinoma.
Escalation: Participant with pancreatic adenocarcinoma who has progressed, is intolerant, has refused, or for whom there is no standard approved therapies that impart significant clinical benefit (no limit to the number of prior treatment regimens).
Unique to South Korea: Participant with pancreatic adenocarcinoma who has refused standard approved therapies is not allowed.
Expansion: Participants with pancreatic adenocarcinoma must have received no more than 2 prior lines of systemic chemotherapy treatment.
Unique to EU: Participant with pancreatic adenocarcinoma must have received at least first-line standard therapies in the metastatic setting \& no more than 2 prior lines of systemic chemotherapy treatment.
If a participant has received a recent blood transfusion, the laboratory tests must be obtained ≥ 1 week after any blood transfusion.
Participant has histologically confirmed diagnosis of gastric/GEJ adenocarcinoma.
Participant has metastatic or locally advanced unresectable gastric/GEJ adenocarcinoma.
Participant with gastric/GEJ adenocarcinoma has progressed \& must not have been previously treated for metastatic disease with either chemotherapy or prior checkpoint inhibitor therapy.
Participant has a human epidermal growth factor receptor 2 (HER2)-negative tumor per local testing.
For CT with oxaliplatin, follow contraception guidelines from time of informed consent through at least 9 months after final study intervention.
Participant must have a PD-L1 CPS ≥ 1.
Participant has histologically confirmed diagnosis of gastric/GEJ adenocarcinoma.
Participant has metastatic or locally advanced unresectable gastric/GEJ adenocarcinoma.
Participant with gastric/GEJ adenocarcinoma must have previously received 1 line of systemic chemotherapy treatment (i.e., documented objective radiological or clinical disease progression after first line platinum \& fluoropyrimidine treatment in the metastatic setting or disease progression during or within 4 months of the last dose of perioperative treatment.
For combination therapy with paclitaxel, female participant must follow contraception guidelines from time of informed consent through at least 7 months after final study intervention.
Participant has histologically or cytologically confirmed diagnosis of pancreatic adenocarcinoma.
Participant has confirmed metastatic or locally advanced unresectable pancreatic adenocarcinoma.
Participant has pancreatic adenocarcinoma, has progressed \& must not have received prior systemic anticancer therapy for their advanced disease. However, participants may have received either neoadjuvant or adjuvant chemotherapy, immunotherapy or other systemic anticancer therapies as long as they were completed at least 6 months prior to enrollment and without disease progression or recurrence.
For CT with oxaliplatin, follow contraception guidelines from time of informed consent through at least 9 months after final study intervention.
Participant has histologically confirmed diagnosis of gastric/GEJ adenocarcinoma.
Participant has metastatic or locally advanced unresectable gastric/GEJ adenocarcinoma.
Participant with gastric/GEJ adenocarcinoma must not have been previously treated for metastatic disease with either chemotherapy or prior checkpoint inhibitor therapy.
Participants have a HER2-negative tumor per local testing.
For CT with oxaliplatin, follow contraception guidelines from time of informed consent through at least 9 months after final study intervention.
Exclusion
Participant has received other investigational agents, or antineoplastic therapy including other immunotherapy or devices concurrently or within 21 days or 5 times the half-life, whichever is shorter, prior to first dose of study intervention administration.
Participant has any condition which makes the participant unsuitable for study participation.
Participant has known immediate or delayed hypersensitivity or contraindication to any component of study intervention.
Participant has had prior severe allergic reaction or intolerance to known ingredients of ASP2138 or other antibodies, including humanized or chimeric antibodies.
Participant weighs \< 40 kg.
Participant has received systemic immunosuppressive therapy, including systemic corticosteroids 14 days prior to first dose of study intervention. Participant using a physiologic replacement dose of hydrocortisone or its equivalent (defined as up to 10 mg per day of prednisone or equivalent), receiving a single daily dose of systemic corticosteroids or receiving systemic corticosteroids as pre-medication for radiologic imaging contrast use are allowed.
Participant has a complete gastric outlet syndrome or a partial gastric outlet syndrome with persistent/recurrent vomiting.
Participant has significant gastric bleeding \&/or untreated gastric ulcers that exclude the participant from participation.
Participant has symptomatic CNS metastases or participant has evidence of unstable CNS metastases even if asymptomatic (e.g., progression on scans). Participants with previously treated CNS metastases are eligible, if they are clinically stable \& have no evidence of CNS progression by imaging for at least 4 weeks prior to start of study intervention \& are not requiring immunosuppressive doses of systemic steroids (\> 10 mg per day of prednisone or equivalent) for longer than 2 weeks.
Participant is known to have HIV infection. However, participants with cluster of differentiation (CD4) + T cell counts \>= 350 cells/µL \& no history of acquired immunodeficiency syndrome (AIDS)-defining opportunistic infections within the past 6 months are eligible.
Participant is known to have active hepatitis B (positive hepatitis B surface antigen \[HBsAg\]) or hepatitis C infection. Testing is required for known history of these infections or as mandated by local requirements.
For participant who is negative for HBsAg, but hepatitis B core antibody (HBc Ab) positive, a hepatitis B virus deoxyribonucleic acid test will be performed \& if positive the participant will be excluded.
Participant with positive hepatitis C virus (HCV) serology, but negative HCV ribonucleic acid (RNA) test results are eligible.
Participant treated for HCV with undetectable viral load results are eligible
Participant has had within 6 months prior to first dose of study intervention any of the following: unstable angina, myocardial infarction, ventricular arrhythmia requiring intervention or hospitalization for heart failure.
Participant has active infection requiring systemic therapy that has not completely resolved within 7 days prior to the start of study intervention.
Participant has active autoimmune disease that has required systemic immunosuppressive treatment within the past 1 month prior to the start of study intervention.
Participant has a clinically significant disease or co-morbidity that may adversely affect the safe delivery of treatment within this study or make the participant unsuitable for study participation.
Participant has psychiatric illness or social situations that would preclude study compliance.
Participant has had a major surgical procedure 28 days before start of study intervention \& has not fully recovered.
Participant has received radiotherapy metastatic or for locally advanced unresectable gastric/GEJ or metastatic pancreatic adenocarcinoma 14 days prior to start of study intervention \& has NOT recovered from any related toxicity.
Participant has another malignancy for which treatment is required.
Participant who has received CLDN18.2-targeted therapy (e.g., zolbetuximab or chimeric antigen receptor CLDN18.2-specific T cells) prior to first dose of study intervention administration is not eligible for dose escalation cohorts. However, a participant who has received CLDN18.2-targeted therapy greater than 28 days or 5 half-lives (whichever is longer) prior to first dose study intervention administration is eligible for dose expansion cohorts only, with the exception of participants who have experienced Grade \>= 3 gastrointestinal toxicity after receiving an CLDN18.2-targeted therapy.
Participant has a history or complication of interstitial lung disease.
Participant has prior severe allergic reaction; suspected, known immediate or delayed hypersensitivity; or intolerance or contraindication to any study intervention (i.e., pembrolizumab \& mFOLFOX6 \[all components\], ramucirumab \& paclitaxel or mFOLFIRINOX \[all components\]).
For 5 FU (fluorouracil): Participant has known dihydropyrimidine dehydrogenase (DPD) deficiency.
Participants who have received systemic immunosuppressive therapy, including systemic corticosteroids 14 days prior to the first dose of study intervention are generally excluded; however, participants using a physiologic replacement dose of hydrocortisone or its equivalent (defined as up to 10 mg per day of prednisone or equivalent), receiving a single daily dose of systemic corticosteroids or receiving systemic corticosteroids as pre-medication for radiologic imaging contrast or for chemotherapy (as part of CT administration) are allowed.
Participant is known to have HIV infection.
NOTE: Differing from monotherapy administration, participants with CD4+ T cell counts ≥ 350 cells/µL \& no history of AIDS-defining opportunistic infections within the past 6 months remain ineligible.
Participant has had uncontrolled high blood pressure within 6 months prior to the first dose of study intervention (Unique to EU: high blood pressure Stage 2 is defined as ≥ 140/90 mmHg).
Participant has a history of ascites requiring drainage more than twice in the past 7 days.
Participant has history of (non-infectious) pneumonitis that required steroids, current pneumonitis, or has a history of interstitial lung disease.
Participant received live-virus vaccination within 30 days prior to the first dose of study intervention.
Participant has a diagnosis of immunodeficiency or is receiving systemic steroid therapy or any other form of immunosuppressive therapy within 7 days prior to the first dose of study intervention or has been diagnosed with an autoimmune disease that has required systemic treatment in past 2 years (i.e., with use of disease modifying agents, corticosteroids or immunosuppressive drugs). Patients that require replacement therapy (e.g., thyroxine \[T4\], insulin, or physiologic corticosteroid replacement therapy for adrenal or pituitary insufficiency, etc.) may be enrolled.
History of cerebrovascular accident or transient ischemic attack within 6 months prior to study intervention.
Participant has significant vascular disease (e.g., aortic aneurysm requiring surgical repair or recent peripheral arterial thrombosis) within 6 months prior to study intervention.
Participant has evidence of a bleeding diathesis or significant coagulopathy.
Participant has initiated new treatment with medications that affect the coagulation cascade with an INR ≥ 2 such as vitamin K antagonists, heparins \& direct thrombin inhibitors or the use of factor Xa inhibitors within 28 days prior to the start of study intervention.
Participant has prior severe allergic reaction; suspected, known immediate or delayed hypersensitivity; or intolerance or contraindication to any study intervention (i.e., pembrolizumab \& CAPOX \[all components\]).
Participants who have received systemic immunosuppressive therapy, including systemic corticosteroids 14 days prior to the first dose of study intervention are generally excluded, however, participants using a physiologic replacement dose of hydrocortisone or its equivalent (defined as up to 10 mg per day of prednisone or equivalent), receiving a single dose of systemic corticosteroids or receiving systemic corticosteroids as pre-medication for radiologic imaging contrast or for chemotherapy (as part of CT administration) are allowed.
Participant is known to have HIV infection.
NOTE: Differing from monotherapy administration, participants with CD4+ T cell counts ≥ 350 cells/μL \& no history of AIDS-defining opportunistic infections within the past 6 months remain ineligible.
Participant has had uncontrolled high blood pressure within 6 months prior to the first dose of study intervention.
Participant has a history of ascites requiring drainage more than twice in the past 7 days.
Participant has known DPD deficiency.
Participant has history of (noninfectious) pneumonitis that required steroids, current pneumonitis, or has a history of interstitial lung disease.
Participant received live-virus vaccination within 30 days prior to the first dose of study intervention.
Participant has a diagnosis of immunodeficiency or is receiving systemic steroid therapy or any other form of immunosuppressive therapy within 7 days prior to the first dose of study intervention or has been diagnosed with an autoimmune disease that has required systemic treatment in past 2 years (i.e., with use of disease modifying agents, corticosteroids or immunosuppressive drugs). Participants who require replacement therapy (e.g., thyroxine \[T4\], insulin, or physiologic corticosteroid replacement therapy for adrenal or pituitary insufficiency, etc.) may be enrolled.
What this trial measures
- Incidence of Dose Limiting Toxicities (DLTs) (Phase 1 Dose Escalation)Up to 28 days
A DLT is defined as any of the prespecified Adverse Events (AEs) (graded using National Cancer Institute Common Terminology Criteria for Adverse Events \[NCI-CTCAE\] version 5.0, except cytokine release syndrome \[CRS\] and immune effector cell-associated neurotoxicity syndrome \[ICANS\] which are graded using American Society for Transplantation and Cellular Therapy \[ASTCT\] consensus grading) or laboratory findings that the investigator or sponsor cannot clearly attribute to a cause other than study drug occurring during the DLT evaluation period.
- Number of participants with Adverse Events (AEs)Up to 27 months
An AE is any untoward medical occurrence temporally associated with the use of study intervention, whether or not considered related to the study intervention. An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of study intervention. This includes events related to the comparator and events related to the (study) procedures.
- Number of participants with serious AEs (SAEs)Up to 27 months
An SAE is defined as any untoward medical occurrence that, at any dose: results in death, is life-threatening, requires inpatient hospitalization or prolongation of existing hospitalization, results in persistent or significant disability/incapacity, is a congenital anomaly/birth defect, or other medically important events.
- Number of participants with laboratory value abnormalitiesUp to 25 months
Number of participants with potentially clinically significant laboratory values.
- Number of participants with vital sign abnormalitiesUp to 27 months
Number of participants with potentially clinically significant vital sign values.
- Number of participants with electrocardiogram (ECG) abnormalitiesUp to 24 months
Number of participants with potentially clinically significant ECG values.
- Number of participants with physical exam abnormalitiesUp to 25 months
Number of participants with potentially clinically significant physical exam values.
- Number of participants at each grade of the Eastern Cooperative Oncology Group (ECOG) performance statusUp to 25 months
The ECOG scale will be used to assess performance status. Grades range from 0 (fully active) to 5 (dead). Negative change scores indicate an improvement. Positive scores indicate a decline in performance.