Henlius receives ODD for HLX22 from European Commission

HLX22 is the first anti-HER2 targeted treatment to receive ODD from both the US Food and Drug Administration (FDA) in March 2025 and from the EU.

An international multicentre Phase III clinical study (HLX22-GC-301) investigated HLX22 combined with trastuzumab and chemotherapy as a first-line therapy for HER2-positive advanced gastric cancer.

The study has obtained new drug clinical trial (IND) approval from regulatory agencies across multiple regions including the US, China, Germany, Japan, Australia, South Korea and others while completing dosing of its first patient.

HLX22 targets HER2 with a differentiated molecular design that allows it to bind to extracellular subdomain IV of HER2.

Its unique binding epitope differs from that of trastuzumab enabling simultaneous binding alongside trastuzumab; this mechanism promotes endocytosis and degradation of HER2 dimers by 40%-80% resulting in enhanced receptor blocking effects on HER2 signalling pathways.

Results from a Phase II clinical trial (HLX22-GC-201), where HLX22 was combined with Hantuyou (trastuzumab), demonstrated improved survival rates and tumour response among patients suffering from HER2-positive gastric or gastroesophageal junction cancers (G/GEJ) when compared against standard chemotherapy alone.

Shanghai Henlius Biotech is developing HLX22 under a sublicense from AbClon, which had earlier licensed it from Alligator Bioscience.

Under the agreement terms, Alligator will receive 35% of AbClon’s revenue from its sublicense agreement with Henlius.

Alligator Bioscience CEO Søren Bregenholt said: “The orphan designation to HLX22 in Europe represents another important regulatory milestone for this programme.

“Following the earlier FDA designation, this reinforces the potential clinical and commercial value of the antibody. While Alligator is not directly involved in the development, we look forward to following its progress as it may contribute future revenue to Alligator.”