Abtiys wins US patent trial, retains exclusive rights to AbClick platform

Abtiys, a next-generation antibody-drug conjugate (ADC) drug development company, said Friday it had won a complete victory in an inter partes review (IPR) proceeding brought by Japan's Ajinomoto before the US Patent Trial and Appeal Board (PTAB).

In its final written decision, PTAB rejected all of Ajinomoto's invalidity claims and upheld the validity of the core US patent covering AbClick®, Abtiys's proprietary site-specific ADC platform technology.

Ajinomoto had challenged the AbClick patent on multiple grounds under US patent law, including written description, enablement, definiteness, novelty and inventive step. PTAB rejected every argument, including those related to procedural and evidentiary matters.

AbClick is a site-specific ADC platform that selectively conjugates a drug to a specific lysine residue (Lys248) in the antibody Fc region, enabling uniform drug-to-antibody ratios (DAR) and large-scale production of pharmaceuticals with consistent quality.

The victory carries significant weight as competition for leadership in the global ADC drug market intensifies. By fending off a challenge from a major global pharmaceutical company, Abtiys has fully secured patent rights and exclusive commercial rights to its foundational platform technology in the United States, the world's largest pharmaceutical market.

"We have firmly established the validity of the core patent protecting the AbClick platform in the United States," said Choi Hyung-seok, chief executive of Abtiys. "Building on this strong patent position, we will expand global partnerships and technology licensing while continuing to advance ADC drug development."