Astellas Pharma has gained approval from the US Food and Drug Administration (FDA) for VYLOY (zolbetuximab-clzb), in conjunction with chemotherapy, for the treatment of advanced gastric and gastroesophageal junction (GEJ) cancer.

This is the first US approval for VYLOY, a therapy targeting claudin (CLDN)-18.2-positive tumours identified through an FDA-approved diagnostic assay, Roche's VENTANA CLDN18 (43-14A) RxDx assay.

The FDA's decision is grounded in the outcomes of the Phase III, global, multi-centre, double-blind, randomised SPOTLIGHT and GLOW clinical trials.

These studies demonstrated that patients with CLDN18.2-positive tumours experienced significant improvements in progression-free survival (PFS) and overall survival (OS) when treated with VYLOY in combination with chemotherapy, compared to placebo and chemotherapy.

Astellas senior vice-president and immuno-oncology development head Moitreyee Chatterjee-Kishore stated: “The approval of VYLOY as the first and only targeted therapy for CLDN18.2-positive patients in the US further delivers on our relentless pursuit of scientific progress for devastating diseases like gastric and GEJ cancers, which are often only discovered at the advanced stage.

“This achievement is the result of years of dedicated research and development focused on targeting a novel biomarker, and we are grateful to the patients, investigators and Astellas team members who have made this important advancement for patients a reality.”

In the SPOTLIGHT trial, VYLOY was evaluated with mFOLFOX6. In the GLOW study, it was combined with CAPOX.

The trials showed that 38% of screened patients had CLDN18.2-positive tumours, defined by a specific level of immunohistochemical staining determined by Roche's assay.

With FDA approval, VYLOY is authorised in five markets globally, following earlier approvals in Japan, the UK, the European Union and South Korea.

The therapy received its first global approval from Japan's Ministry of Health, Labour and Welfare (MHLW) in March 2024, and gained subsequent endorsements by the UK's Medicines and Healthcare products Regulatory Agency (MHRA) in August, the European Commission in September, and South Korea's Ministry of Food and Drug Safety.

Astellas continues to seek approvals for VYLOY in other regions.