FGFR2b is an emerging protein biomarker overexpressed in 20%–30% of G/GEJ cancers, as detected by IHC.1,2,*
ABOUT GASTRIC CANCER
Gastric cancer is the fifth most common cancer and the fifth leading cause of cancer-related death worldwide3
61%
of patients with gastric cancer have advanced disease† at the time of diagnosis4
5-year relative survival rates by stage at diagnosis from 2014 to 20204,‡
The 5-year relative survival rate for patients with distantly metastatic gastric cancer at diagnosis is only 7% in the United States‡
*Approximate range based on 910 prescreened patients for a phase 2 trial in locally advanced or metastatic G/GEJ cancer, of which 274 patients (30%) were prescreened positive for FGFR2b any 2+/3+ tumor cell staining by IHC, and on the 155 enrolled patients, of which 96 (62%) exhibited FGFR2b ≥ 10% 2+/3+ tumor cell staining by IHC.1
†This includes patients with regional disease, or those whose cancer have spread to regional lymph nodes, and metastatic disease at the time of diagnosis. There are 26,890 estimated new cases.4
‡Assessed between 2014 and 2020 in the United States.4
1L, first line; FGFR2b, fibroblast growth factor receptor 2, isoform IIIb; G/GEJ, gastric/gastroesophageal junction; IHC, immunohistochemistry.
FGFR2b PROTEIN OVEREXPRESSION
FGFR2b protein overexpression is an emerging biomarker prevalent in 20%–30% of patients with advanced G/GEJ cancer1,*
Overexpression of FGFR2b protein drives tumorigenesis6,7
FGFR2b drives multiple cellular functions6,7
FGFR2b protein overexpression may be prognostic and associated with shorter survival in G/GEJ cancers9
*Approximate range based on the 910 prescreened patients for a phase 2 trial in locally advanced or metastatic G/GEJ cancer, of which 274 patients (30%) were prescreened positive for FGFR2b any 2+/3+ tumor cell staining by IHC, and on the 155 enrolled patients, of which 96 patients (62%) exhibited FGFR2b ≥ 10% 2+/3+ tumor cell staining by IHC.1
AKT, protein kinase B; CBL, Casitas B lineage lymphoma; FGF, fibroblast growth factor; FGFR2b, fibroblast growth factor receptor 2, isoform IIIb; FRS2a, FGFR substrate 2a; GAB1, GRB2-associated-binding protein 1; G/GEJ, gastric/gastroesophageal junction; GRB2, growth factor receptor-bound 2; Ig, immunoglobulin; IHC, immunohistochemistry; MAPK, mitogen-activated protein kinase; MEK, mitogen-activated protein kinase kinase; MKP1, mitogen-activated protein kinase phosphatase 1; MKP3, mitogen-activated protein kinase phosphatase 3; P, phosphate; PI3K, phosphoinositide 3-kinase; PI3K-AKT, phosphoinositide 3-kinase Akt protein kinase B; RaF, proto-oncogene, serine/threonine kinase; RAS, rat sarcoma; RAS-MAPK, rat sarcoma mitogen-activated protein kinase; RTK, receptor tyrosine kinase; SEFB, S-adenosyl methionine-dependent methyltransferase; SoS, son of sevenless; SPRY, sprouty protein; TM, transmembrane.
BIOMARKER DETECTION CONSIDERATIONS FOR GASTRIC CANCER
Similar to other gastric cancer biomarkers, FGFR2b protein overexpression can be detected by IHC, a method to evaluate protein expression2,§
Emerging
Actionable
FGFR2b protein overexpression by IHC is defined as 2+/3+ staining10
No Staining (0) 
Low–Moderate (1+) 
Moderate–Strong (2+) 
Strong (3+) §Currently, FGFR2b testing is in the context of investigational clinical trials with no approved diagnostic test in the market.2
CLDN18.2, claudin-18 isoform 2; dMMR, deficient mismatch repair; FGFR2b, fibroblast growth factor receptor 2, isoform IIIb; HER2, human epidermal growth factor receptor 2; IHC, immunohistochemistry; ISH, in situ hybridization; MSI-H, microsatellite instability-high; NGS, next-generation sequencing; PCR, polymerase chain reaction; PD-L1, programmed cell death ligand 1.
RESOURCES
Watch the FGFR2b DSE video
The impact of targeting FGFR2b in first-line G/GEJ cancer is being evaluated. Amgen is committed to exploring the full potential of FGFR2b as an emerging biomarker2,11
DSE, disease state education; G/GEJ, gastric/gastroesophageal junction; FGFR2b, fibroblast growth factor receptor 2, isoform IIIb.
