FDA Grants Orphan Drug Status to Adcentrx’s ADRX-0405 for Gastric Cancer

Adcentrx Therapeutics, a clinical-stage biotech company specializing in Antibody-Drug Conjugate (ADC) therapies, announced that the U.S. Food and Drug Administration (FDA) has granted orphan drug designation to its investigational drug ADRX-0405 for treating gastric cancer.

ADRX-0405 is a STEAP1-targeting ADC currently under evaluation in a Phase 1a/b clinical trial involving advanced solid tumors such as metastatic castration-resistant prostate cancer, gastric cancer, and non-small cell lung cancer. While STEAP1 is mainly linked to prostate cancer, its expression in gastric cancer makes this a promising target for future development.

Hui Li, Ph.D., Founder and CEO of Adcentrx, said the designation is a significant milestone, underscoring the potential of ADRX-0405 to benefit patients with gastric cancer. The company is encouraged by the progress in its Phase 1a trial and plans to continue assessing the drug’s safety, tolerability, and anti-tumor effects in gastric and other cancers.

Gastric cancer is often diagnosed late and remains a serious health challenge, with the American Cancer Society estimating 30,300 new U.S. cases in 2025. The orphan drug designation supports development of treatments for rare diseases affecting fewer than 200,000 people in the U.S., offering benefits such as funding opportunities, tax credits, fee waivers, and up to seven years of market exclusivity upon approval.