CancerFax
CLINICAL GUIDE ยท TARGETED THERAPY

TARGETED THERAPY FOR
GASTRIC CANCER

The complete landscape of targeted therapy in gastric cancer โ€” from HER2-directed trastuzumab and T-DXd through CLDN18.2-directed zolbetuximab to VEGFR2 inhibition and emerging FGFR2b and novel targets being investigated in Chinese clinical trials.

analyticsAt a Glance

  • check_circleGastric cancer targeted therapy has expanded from one target (HER2) to four actionable biomarkers in routine practice
  • check_circleCLDN18.2 is now the largest novel biomarker-defined group โ€” zolbetuximab NMPA-approved in China 2024
  • check_circleFGFR2b, VEGFR2, and emerging ADC targets expand precision medicine options beyond HER2
  • check_circleCancerFax coordinates targeted therapy access at specialist Chinese gastric cancer centres
Reviewed by: CancerFax Medical Team, Oncology & Haematology SpecialistsLast reviewed: June 2, 2026

The Targeted Therapy Revolution in Gastric Cancer

Gastric cancer was once considered a molecularly undifferentiated disease treated with generic platinum-fluoropyrimidine chemotherapy. This view has been comprehensively revised. Since the ToGA trial established HER2-directed therapy in 2010, the gastric cancer molecular landscape has been systematically characterised โ€” revealing distinct, actionable subgroups that now define the first-line and second-line treatment landscape.

โ€œThe question is no longer 'does this patient have gastric cancer?' โ€” it is 'which molecular subtype does this patient have, and which targeted agents address that subtype?'โ€
  • From One Target to Four

    In 2010, HER2 was the only actionable target in gastric cancer. By 2025, four clinically actionable biomarkers guide treatment selection: HER2 (trastuzumab, T-DXd), PD-L1/MSI (checkpoint inhibitors), CLDN18.2 (zolbetuximab), and VEGFR2 (ramucirumab). FGFR2b and additional targets are advancing through trials.

  • Biomarker Testing Is Now Mandatory

    Complete biomarker profiling at the point of advanced/metastatic gastric cancer diagnosis is now the standard of care. Missing a biomarker result at diagnosis can mean missing the most effective first-line treatment โ€” a clinical error with measurable survival consequences.

Gastric Cancer Targeted Agents by Biomarker and Line

A comprehensive reference of approved and trial-available targeted agents in gastric cancer โ€” organised by biomarker, line of therapy, and availability in China.

BiomarkerTarget / AgentLineEvidence BasisChina Availability
HER2 (IHC 3+ or 2+/ISH+)Trastuzumab + chemo1st lineToGA Phase III (Lancet 2010)Standard โ€” all major centres
HER2 (IHC 3+ or 2+)T-DXd (trastuzumab deruxtecan)2nd lineDESTINY-Gastric01/02NMPA approved
HER2-overexpressingRC48 (disitamab vedotin)2nd lineRC48-C007 Phase II/IIINMPA approved โ€” China domestic
CLDN18.2 โ‰ฅ75% cells 2+/3+ / HER2โˆ’Zolbetuximab + FOLFOX/CAPOX1st lineSPOTLIGHT + GLOW Phase IIINMPA approved 2024
VEGFR2 (all advanced gastric)Ramucirumab ยฑ paclitaxel2nd lineREGARD + RAINBOW Phase IIIAvailable at major centres
FGFR2b overexpressionBemarituzumab + mFOLFOX61st line (trial)BEMA-1 Phase II; FORTITUDE Phase IIIActive trials at Chinese centres
HER2+ (bispecific novel)Zanidatamab (ZW25)2nd line+ (trial)Phase I/II activeTrial access at Chinese centres
CLDN18.2+ (CAR-T target)CT-041 tanajducel (CAR-T)2nd/3rd (trial)Phase I/II (CARsgen)Trial at CARsgen-affiliated centres

How Many Gastric Cancer Patients Are Eligible for Each Targeted Therapy?

An indicative overview of the approximate proportion of advanced gastric cancer patients carrying each targetable biomarker โ€” illustrating the potential reach of each targeted therapy approach.

Biomarker Prevalence in Advanced Gastric Cancer (Approximate)

Approximate prevalence estimates from published gastric cancer biomarker studies and trial eligibility data. Overlap exists (e.g. CLDN18.2/HER2 co-positive ~8โ€“10%).

  • PD-L1 CPS โ‰ฅ5 (nivolumab eligible)~60โ€“65%
  • CLDN18.2 high (โ‰ฅ75% cells 2+/3+)~38โ€“40%
  • MSI-H/dMMR (pembrolizumab monotherapy)~5โ€“10%
  • HER2 positive (IHC 3+ or 2+/ISH+)~15โ€“20%
  • FGFR2b overexpression (bemarituzumab)~7โ€“10%

The Recommended Biomarker Testing Pathway at Diagnosis

Complete biomarker testing at diagnosis is essential for gastric cancer treatment planning. This is the recommended sequence and rationale.

  1. 1

    HER2 IHC + ISH

    First and most urgent biomarker test. HER2 positivity (IHC 3+ or IHC 2+/ISH+) defines eligibility for trastuzumab in first-line and T-DXd at second-line. Use gastric cancer-specific IHC scoring criteria โ€” not breast cancer criteria.

  2. 2

    CLDN18.2 IHC

    Claudin 18.2 testing using the validated SPOTLIGHT/GLOW scoring threshold (โ‰ฅ75% cells 2+/3+) identifies the zolbetuximab-eligible population. Critical for HER2-negative patients who are the primary zolbetuximab target.

  3. 3

    MSI / MMR Testing

    MSI-H or dMMR gastric cancer (IHC for MLH1, MSH2, MSH6, PMS2 or PCR-based MSI) identifies the subgroup eligible for PD-1 inhibitor monotherapy in first-line. Also prognostically relevant.

  4. 4

    PD-L1 CPS Scoring

    PD-L1 CPS โ‰ฅ5 (22C3 antibody pharmDx assay) identifies the population eligible for nivolumab addition in CheckMate-649. PD-L1 should be tested concurrently with MSI and HER2.

  5. 5

    FGFR2b Expression

    FGFR2b IHC or ISH testing identifies the population potentially eligible for bemarituzumab in the context of clinical trials. This test is not yet standard outside a trial setting but is increasingly available at academic centres.

  6. 6

    NGS-Based Comprehensive Profiling

    Comprehensive genomic profiling (CGP) by NGS identifies additional actionable mutations โ€” KRAS G12C (sotorasib-eligible), PIK3CA, RNF43, RHOA, and CDH1 โ€” that may affect trial eligibility and emerging targeted therapy access.

Gastric Cancer Targeted Therapy โ€” Key Numbers

The most important quantitative references in gastric cancer targeted therapy.

  • 4+Currently actionable biomarkers in standard advanced gastric cancer careHER2, CLDN18.2, PD-L1/MSI, and VEGFR2 โ€” all with approved agents โ€” represent a molecular precision medicine landscape unrecognised a decade ago.
  • ~63%Proportion of advanced gastric cancer patients with at least one actionable biomarkerThe majority of advanced gastric cancer patients have at least one biomarker-defined treatment option โ€” making complete testing at diagnosis essential.
  • 2024Year of NMPA approval for zolbetuximab โ€” the most recent approved targeted agentChina's NMPA was among the first regulators to approve zolbetuximab โ€” giving Chinese patients and international patients in China early access.

Frequently Asked Questions: Targeted Therapy for Gastric Cancer

  • Do I need all biomarker tests even if my oncologist only ordered HER2?

    Yes โ€” incomplete biomarker testing risks missing the most effective treatment for your case. If only HER2 was tested at diagnosis, you may be missing CLDN18.2 positivity (eligible for zolbetuximab), MSI-H status (eligible for pembrolizumab monotherapy), or PD-L1 CPS โ‰ฅ5 (eligible for nivolumab addition). These are not optional refinements โ€” they are treatment-determining tests that should be performed on every patient with newly diagnosed advanced gastric cancer. CancerFax identifies gaps in your biomarker panel and advises on supplementary testing on archival tissue or repeat biopsy.

  • What if my tumour is positive for both CLDN18.2 and HER2?

    Co-positivity for CLDN18.2 and HER2 (approximately 8โ€“10% of gastric cancers) presents a treatment dilemma. Zolbetuximab's approved indication specifically excludes HER2-positive patients โ€” so the current standard for co-positive patients is trastuzumab-based first-line treatment. The question of whether co-positive patients might benefit from combination trastuzumab + zolbetuximab is under active clinical investigation. CancerFax can identify specific trials designed for CLDN18.2+/HER2+ co-positive patients at Chinese centres.

  • Are there targeted therapies for gastric cancer that are available in China but not in my country?

    Yes โ€” several agents are available in China before other markets: zolbetuximab (NMPA approved 2024, ahead of many Western markets), RC48/disitamab vedotin (NMPA approved, developed in China), and Chinese domestic PD-1 inhibitors (sintilimab, camrelizumab) at substantially lower cost than Western originator agents. Additionally, Chinese clinical trials provide access to bemarituzumab, novel bispecific antibodies, and CLDN18.2-directed CAR-T therapy (CT-041) not yet available elsewhere. CancerFax identifies which of these options is most relevant to your specific biomarker profile.

How CancerFax Helps

CancerFax is a specialist cancer access and patient-navigation platform. We help patients and families understand their options, organise medical records, coordinate hospital communication, and support cross-border treatment planning where appropriate.

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Medical Record Review

We help collect and organise reports, scans, pathology, biomarker results, and treatment history for structured case review.

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Eligibility Coordination

We communicate with hospitals or trial teams to assess whether a case may be suitable for further screening.

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Hospital Communication

We support appointment coordination, document submission, translation, and direct communication with international departments.

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Travel & Admission Support

For international patients, we help with practical coordination โ€” travel planning, hospital admission guidance, and local support.

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Treatment & Trial Navigation

If this option is not suitable, we help explore other relevant treatments, clinical trials, or advanced care pathways.

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End-to-end Coordination

From inquiry through to follow-up, our coordinators provide a single point of contact for the family.

CancerFax does not guarantee treatment access, eligibility, or clinical outcome. Our role is to help patients access accurate information, structured review, and appropriate specialist pathways.

Has Your Gastric Cancer Had a Complete Biomarker Panel?

CancerFax reviews your existing biomarker results and identifies whether the full panel has been tested โ€” recommending additional testing where needed โ€” then coordinates targeted therapy access at specialist centres in China.

This content is for informational purposes only and does not constitute medical advice. Always consult a qualified oncologist before making treatment decisions.