MFDS Approves Vyloy 100 mg with New Diagnostic Support, But Access Challenges Remain
Astellas Pharma Korea's Vyloy 100 mg (zolbetuximab), the first monoclonal antibody targeting Claudin 18.2 (CLDN18.2), has received approval from the Ministry of Food and Drug Safety (MFDS), introducing a novel treatment option for patients with gastric adenocarcinoma.
In September, MFDS authorized Vyloy as a first-line treatment, combined with chemotherapy, for unresectable locally advanced or metastatic CLDN18.2-positive, HER2-negative gastric and gastroesophageal junction adenocarcinoma. CLDN18.2, a protein frequently overexpressed on gastric cancer cells, is involved in cell proliferation, differentiation, and metastasis. Zolbetuximab targets CLDN18.2 to combat these cancer cells effectively.
In the Phase 3 SPOTLIGHT trial, the zolbetuximab plus FOLFOX combination showed a progression-free survival (PFS) of 10.6 months, surpassing the control group’s 8.7 months. Overall survival (OS) also improved by 2.7 months, reaching 18.2 months. The Glow study further supported zolbetuximab’s efficacy in combination with CAPOX, with PFS extended to 8.2 months and OS reaching 14.4 months compared to the control group.
Additionally, the MFDS has approved the VENTANA CLDN18 (43-14A) RxDx Assay to identify CLDN18.2-positive patients, expanding diagnostic support for targeted treatment.
However, experts caution that patient access may remain restricted. Currently, only PD-L1 and ALK biomarkers are covered for reimbursement in companion diagnostics. Without reimbursement for CLDN18.2 testing, hospitals are less likely to adopt the equipment, and the administrative process to include a new biomarker may take over five months, delaying diagnoses.
Experts advocate for streamlined biomarker addition in companion diagnostics, stating, “The process typically takes 3-6 months, and enhancing reimbursement policies is critical for accelerating access to cancer treatments.”