Antengene Initiates Phase I Study for Innovative Autoimmune Treatment ATG-201

On November 5, 2026, Antengene Corporation Limited, a prominent biotech firm listed on the Hong Kong Stock Exchange (SEHK: 6996.HK), declared a major advancement in its clinical research efforts by dosing the first patient in China for the Phase I ATTRACT study. This study aims to assess ATG-201, a proprietary CD19 x CD3 bispecific T-cell engager antibody (TCE), in adult patients afflicted with B cell-mediated autoimmune diseases.

The ATTRACT study is a multi-site endeavor taking place in both China and Australia. As the study progresses within China, significant regulatory steps have been achieved in Australia, including the approval from the Human Research Ethics Committee (HREC) and the completion of the Clinical Trial Notification (CTN) process with the Therapeutic Goods Administration (TGA). These complete regulatory approvals underscore Antengene's commitment to advancing innovative treatments for unmet medical needs.

ATG-201 is engineered to precisely target and eliminate B cells expressing CD19, a technique that integrates state-of-the-art steric hindrance masking technology. This technology aims to leverage the body’s immune system effectively, enhancing its potential to treat diseases characterized by B cell dysfunction. The dual targeting mechanism of ATG-201 interacts with both T and B cells via CD3 and CD19, holding promise for a range of B cell-mediated conditions.

The clinical trial is set up in two segments: Dose Escalation (Part I) and Dose Expansion (Part II). The primary focus will be to evaluate the safety and tolerability of ATG-201 while determining the recommended Phase II dose (RP2D). Furthermore, the trial will assess secondary endpoints including pharmacokinetic (PK) and pharmacodynamic (PD) profiles, immunogenicity, and a preliminary assessment of efficacy.

Leading the study is Professor Zhanguo Li from Peking University People’s Hospital, who emphasized the dire need for new therapies targeting refractory B cell-mediated autoimmune diseases. These conditions often feature low remission rates and high relapse risks for patients, accompanied by serious long-term safety concerns. ATG-201 aims to bridge this therapeutic gap by offering a targeted immunotherapeutic option for affected individuals.

Professor Li remarked, “The initiation of the first patient dosing is an important milestone in our quest to provide an effective treatment avenue for patients struggling with these difficult-to-treat conditions. I am eager to evaluate the comprehensive safety and preliminary efficacy of ATG-201 throughout this clinical trial.”

In addition, Antengene has formed a partnership with UCB, allowing UCB to acquire worldwide exclusive rights for further development, manufacturing, and commercialization of ATG-201, along with access to the related manufacturing technology. Meanwhile, Antengene retains the responsibility for conducting the initial phase I clinical trials in China and Australia.

Antengene Corporation Limited is dedicated to the discovery, development, and commercialization of first-in-class and/or best-in-class therapies aimed at addressing significant unmet medical needs. Its clinical development pipeline is extensive, featuring innovative candidates such as ATG-022, ATG-037, ATG-101, ATG-125, ATG-207, and many others targeting various cancers and autoimmune diseases.

With 35 investigational new drug (IND) approvals to date in both the U.S. and Asia, along with successful new drug application (NDA) approvals across ten Asia Pacific markets, Antengene continues to be a significant player in the biotechnology landscape. Its most recognized asset, XPOVIO® (selinexor), is already approved in several key markets, demonstrating the company’s capability in moving forward with transformative treatment options.

As the Phase I ATTRACT study progresses, the biotechnology community will be watching closely for updates that could shape the future of treatment for patients with B cell-mediated autoimmune diseases. The trial's results may provide critical insights into the safety and efficacy of this innovative therapy, potentially ushering in new hope for countless individuals in need of effective treatment strategies.