A Study Evaluating Bemarituzumab in Combination With Other Anti-cancer Therapies in Subjects With Previously Untreated Advanced Gastric or Gastroesophageal Junction Cancer. (FORTITUDE-103)

A Phase 1b/2 Study Evaluating the Safety, Tolerability, Efficacy, and Pharmacokinetics of Bemarituzumab in Combination With Other Anti-cancer Therapies in Subjects With Previously Untreated Advanced Gastric or Gastroesophageal Junction Cancer (FORTITUDE-103).

The main objectives of this study are to evaluate the safety and tolerability of bemarituzumab in combination with other anti-cancer therapies, and to evaluate the efficacy of bemarituzumab in combination with S-1 and oxaliplatin (SOX) and nivolumab as assessed by objective response.

Study Overview

• Status: Terminated
• Conditions: Gastric Cancer; Gastroesophageal Junction Cancer
• Intervention / Treatment: Drug: Bemarituzumab; Drug: CAPOX; Drug: Nivolumab; Drug: SOX

• Study Type: Interventional
• Enrollment (Actual): 72
• Phase: Phase 2; Phase 1

Contacts and Locations

Study Locations

• Japan
  • Aichi-ken
    • Toyoake-shi, Aichi-ken, Japan, 470-1192
      • Fujita Health University Hospital
  • Aomori
    • Hirosaki-shi, Aomori, Japan, 036-8563
      • Hirosaki University Hospital
  • Chiba
    • Chiba, Chiba, Japan, 260-8677
      • Chiba University Hospital
  • Ehime
    • Matsuyama, Ehime, Japan, 791-0280
      • National Hospital Organization Shikoku Cancer Center
  • Fukui
    • Fukui-shi, Fukui, Japan, 910-8526
      • Fukui Prefectural Hospital
  • Fukuoka
    • Fukuoka, Fukuoka, Japan, 812-8582
      • Kyushu University Hospital
  • Fukushima
    • Fukushima, Fukushima, Japan, 960-1295
      • Fukushima Medical University Hospital
  • Gifu
    • Gifu, Gifu, Japan, 501-1194
      • Gifu University Hospital
    • Ogaki-shi, Gifu, Japan, 503-8502
      • Ogaki Municipal Hospital
  • Gunma
    • Maebashi, Gunma, Japan, 371-8511
      • Gunma University Hospital
    • Ota-shi, Gunma, Japan, 373-8550
      • Gunma Prefectural Cancer Center
  • Hiroshima
    • Hiroshima, Hiroshima, Japan, 734-8551
      • Hiroshima University Hospital
    • Hiroshima, Hiroshima, Japan, 730-8518
      • Hiroshima City Hiroshima Citizens Hospital
  • Ibaraki
    • Kasama-shi, Ibaraki, Japan, 309-1793
      • Ibaraki Prefectural Central Hospital
  • Ishikawa-ken
    • Kanazawa, Ishikawa-ken, Japan, 920-8530
      • Ishikawa Prefectural Central Hospital
  • Kagawa-ken
    • Kita-gun, Kagawa-ken, Japan, 761-0793
      • Kagawa University Hospital
  • Kanagawa
    • Kawasaki-shi, Kanagawa, Japan, 216-8511
      • St Marianna University Hospital
    • Yokohama, Kanagawa, Japan, 241-8515
      • Kanagawa Prefectural Hospital Organization Kanagawa Cancer Center
  • Kochi
    • Kochi, Kochi, Japan, 781-8555
      • Kochi Health Sciences Center
  • Kyoto
    • Kyoto, Kyoto, Japan, 606-8507
      • Kyoto University Hospital
  • Miyagi
    • Sendai, Miyagi, Japan, 980-8574
      • Tohoku University Hospital
  • Okayama-ken
    • Okayama, Okayama-ken, Japan, 700-8558
      • Okayama University Hospital
  • Osaka
    • Osaka, Osaka, Japan, 558-8558
      • Osaka General Medical Center
    • Takatsuki-shi, Osaka, Japan, 569-8686
      • Osaka Medical and Pharmaceutical University Hospital
  • Shizuoka
    • Shizuoka, Shizuoka, Japan, 420-8527
      • Shizuoka General Hospital
    • Sunto-gun, Shizuoka, Japan, 411-8777
      • Shizuoka Cancer Center
  • Tochigi
    • Shimotsuga-gun, Tochigi, Japan, 321-0293
      • Dokkyo Medical University Hospital
  • Tokyo
    • Chuo-ku, Tokyo, Japan, 104-0045
      • National Cancer Center Hospital
    • Koto-ku, Tokyo, Japan, 135-8550
      • The Cancer Institute Hospital of Japanese Foundation for Cancer Research
    • Minato-ku, Tokyo, Japan, 108-8639
      • IMSUT Hospital, The Institute of Medical Science The University of Tokyo
  • Toyama
    • Toyama, Toyama, Japan, 930-0194
      • Toyama University Hospital
• Singapore
  • Singapore, Singapore, 119074
    • National University Hospital
• South Korea
  • Goyang-si Gyeonggi-do, South Korea, 10408
    • National Cancer Center
  • Seongnam-si, Gyeonggi-do, South Korea, 13620
    • Seoul National University Bundang Hospital
  • Seoul, South Korea, 03080
    • Seoul National University Hospital
  • Seoul, South Korea, 05505
    • Asan Medical Center
  • Seoul, South Korea, 03722
    • Severance Hospital Yonsei University Health System
  • Seoul, South Korea, 06351
    • Samsung Medical Center
  • Seoul, South Korea, 08308
    • Korea University Guro Hospital
• Taiwan
  • Taipei, Taiwan, 10002
    • National Taiwan University Hospital
  • Taipei, Taiwan, 11217
    • Taipei Veterans General Hospital
• United States
  • New York
    • Northport, New York, United States, 11768
      • Northport Veterans Affairs Medical Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 100 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Adults with unresectable, locally advanced or metastatic gastric or gastroesophageal junction cancer not amendable to curative therapy.
• Ability to provide tumor sample, either archival (obtained within 6 months to joining study) or fresh biopsy.
• For certain arms for Part 1, FGFR2b overexpression positive defined as any FGFR2b 2+/3+ TC determined by centrally performed immunohistochemistry (IHC), based on tumor sample provided.
• For Part 2, FGFR2b overexpression positive defined as FGFR2b ≥10% 2+/3+ TC determined by centrally performed IHC testing, based on tumor sample provided.
• Easter Cooperative Oncology Group (ECOG) performance score less than or equal to 1.
• Measurable or non-measurable disease as long as evaluable by Response Evaluation Criteria Solid Tumors (RECIST) version 1.1
• Participant has no contradictions to CAPOX/SOX plus or minus nivolumab.
• Adequate organ function.
• For Part 2, measurable disease according to RECIST v1.1.

Exclusion Criteria:

• Prior treatment for metastatic or unresectable disease (Note: prior adjuvant or neo-adjuvant therapy for local disease is allowed if ended more than 6 months of 1st dose).
• Prior treatment with any selective inhibitor of fibroblast growth factor - fibroblast growth factor receptor (FGF-FGFR) pathway.
• Known human epidermal growth factor receptor 2 (HER2) positive
• Untreated or symptomatic central nervous system (CNS) disease or brain metastases.
• Peripheral sensory neuropathy greater than or equal to Grade 2.
• Clinically significant cardiac disease.
• Other malignancy within the last 2 years (exceptions for definitively treated disease).
• Chronic or systemic ophthalmological disorders.
• Major surgery or other investigational study within 28 days of first study treatment dose.
• Palliative radiotherapy within 14 days of first study treatment dose.
• Abnormalities of the cornea that may pose an increased risk of developing a corneal ulcer.
• History or evidence of systemic disease or ophthalmological disorders requiring chronic use of ophthalmic corticosteroids.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Non-Randomized
• Interventional Model: Sequential Assignment
• Masking: None (Open Label)

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Part 1 Cohort A: Bemarituzumab with CAPOX	Drug: Bemarituzumab; Intravenous (IV) infusion; Drug: CAPOX; CAPOX administered as a combination of oxaliplatin as an IV infusion and capecitabine orally as tablets.
Experimental: Part 1 Cohort C: Bemarituzumab with CAPOX and Nivolumab	Drug: Bemarituzumab; Intravenous (IV) infusion; Drug: CAPOX; CAPOX administered as a combination of oxaliplatin as an IV infusion and capecitabine orally as tablets.; Drug: Nivolumab; IV infusion.
Experimental: Part 1 Cohort D: Bemarituzumab with SOX and Nivolumab	Drug: Bemarituzumab; Intravenous (IV) infusion; Drug: Nivolumab; IV infusion.; Drug: SOX; SOX administered as a combination of oxaliplatin as an IV infusion and S-1 orally.
Experimental: Part 2: Bemarituzumab with SOX and Nivolumab.	Drug: Bemarituzumab; Intravenous (IV) infusion; Drug: Nivolumab; IV infusion.; Drug: SOX; SOX administered as a combination of oxaliplatin as an IV infusion and S-1 orally.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Part 1: Number of Participants Who Experience a Dose-limiting Toxicity (DLT)	Day 1 up to Day 21
Part 1: Number of Participants Who Experience a Treatment-emergent Adverse Event (TEAE)	Day 1 to end of treatment (up to approximately 1 year)
Part 2: Objective Response (OR) as per Response Evaluation Criteria in Solid Tumors (RECIST v1.1)	Up to 30 Months

Secondary Outcome Measures

Outcome Measure	Time Frame
Part 1: Area Under the Concentration-time Curve (AUC) of Bemarituzumab	Day 1 to end of treatment (up to approximately 1 year)
Part 1: Maximum Observed Concentration (Cmax) of Bemarituzumab	Day 1 to end of treatment (up to approximately 1 year))
Part 1: Observed Concentration at the end of a Dose Interval (Ctrough) of Bemarituzumab	Day 1 to end of treatment (up to approximately 1 year)
Part 1: OR per RECIST v1.1	Up to 2 years
Part 1: Duration of Response (DoR) per RECIST v1.1	Up to 2 years
Part 1: Disease Control Rate (DCR)	Up to 2 years
Part 1: Progression-free Survival (PFS) per RECIST v1.1	Up to 2 years
Part 1: Overall Survival (OS)	Up to 2 years
Part 2: Number of Participants Who Experience TEAEs	Up to 30 months
Part 2: DoR per RECIST v1.1	Up to 30 months
Part 2: Time to Response (TTR) per RECIST v1.1	Up to 30 months
Part 2: Disease Control (DC) per RECIST v1.1	Up to 30 months
Part 2: PFS per RECIST v1.1	Up to 30 months
Part 2: OS	Up to 30 months

Collaborators and Investigators

• Sponsor: Amgen
• Investigators: Study Director: MD, Amgen

Publications and helpful links

Helpful Links

• AmgenTrials clinical trials website

Study record dates

Study Major Dates

• Study Start (Actual): May 17, 2022
• Primary Completion (Actual): November 21, 2025
• Study Completion (Actual): November 21, 2025

Study Registration Dates

• First Submitted: April 4, 2022
• First Submitted That Met QC Criteria: April 4, 2022
• First Posted (Actual): April 12, 2022

Study Record Updates

• Last Update Posted (Actual): July 29, 2026
• Last Update Submitted That Met QC Criteria: July 28, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Keywords: Gastric Cancer; Gastroesophageal Junction Cancer; Bemarituzumab; FGFR2b Overexpression
• Additional Relevant MeSH Terms: Neoplasms by Site; Neoplasms; Gastrointestinal Neoplasms; Digestive System Neoplasms; Digestive System Diseases; Gastrointestinal Diseases; Stomach Diseases; Stomach Neoplasms; Amino Acids, Peptides, and Proteins; Proteins; Antibodies, Monoclonal, Humanized; Antibodies, Monoclonal; Antibodies; Immunoglobulins; Immunoproteins; Blood Proteins; Serum Globulins; Globulins; Nivolumab; bemarituzumab
• Other Study ID Numbers: 20210099

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: De-identified individual patient data for variables necessary to address the specific research question in an approved data sharing request.
• IPD Sharing Time Frame: Data sharing requests relating to this study will be considered beginning 18 months after the study has ended and either 1) the product and indication have been granted marketing authorization in both the US and Europe or 2) clinical development for the product and/or indication discontinues and the data will not be submitted to regulatory authorities. There is no end date for eligibility to submit a data sharing request for this study.
• IPD Sharing Access Criteria: Qualified researchers may submit a request containing the research objectives, the Amgen product(s) and Amgen study/studies in scope, endpoints/outcomes of interest, statistical analysis plan, data requirements, publication plan, and qualifications of the researcher(s). In general, Amgen does not grant external requests for individual patient data for the purpose of re-evaluating safety and efficacy issues already addressed in the product labelling. Requests are reviewed by a committee of internal advisors. If not approved, a Data Sharing Independent Review Panel will arbitrate and make the final decision. Upon approval, information necessary to address the research question will be provided under the terms of a data sharing agreement. This may include anonymized individual patient data and/or available supporting documents, containing fragments of analysis code where provided in analysis specifications. Further details are available at the URL below.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ICF; CSR

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No