TAIPEI, October 30, 2025 – REGiMMUNE Limited (“REGiMMUNE” or “the Company”), a clinical stage biopharma company developing novel immune therapeutics targeting regulatory T cells (Treg), presented preclinical data of its antibody program at the meeting of Antibody Engineering & Therapeutics Asia 2025 in Kyoto, Japan from Oct. 20 – 22.

REGiMMUNE, while pursuing RGI-2001 in advanced clinical development for (Graft vs Host Disease (GvHD), armed with our long-time expertise in human immunology and Treg cells, has been actively developing its therapeutic antibody program.  This pipeline currently includes RGI-6004 and AB01, both targeting tumor infiltrating Treg cells, reflecting the two strategies of therapeutic modulation of Treg cells, namely, depleting vs silencing, and AB08-H1 targeting a surface marker shared by blood-borne and solid malignancies.

The presentation in Kyoto included RGI-6004 and AB08-H1.  RGI-6004 was developed to highly selectively target tumor infiltrating Treg cells while maintaining all other immune effector cells intact to alleviate the immune suppression in the tumor microenvironment, and consequently enhance anti-cancer immunity.  AB08-H1 is an antibody developed to kill malignant cells of Hodgkin & Non-Hodgkin diseases and solid cancer cells via a unique target.

RGI-6004, an Afucosylated Antibody to Target GARP/LAP-TGFβ1 for Selective Depletion of Activated Tregs.  RGI-6004, a fully human IgG1 against GARP/Latent-TGFb1 complex, designed to deplete tumor infiltrating activated Treg cells. The antibody specifically binds to activated human Treg cells with high affinity, but none to non-activated Treg cells, and CD4+ and CD8+ T effector cells.  The antibody recognizes tumor infiltrating Treg cells in clinical solid tumor tissues. Its afucosylated version highly selectively depletes activated Treg cells with a significantly enhanced efficacy of ~10 pM, but none of CD4+ and CD8+ effector T cells, while granzyme B induction & proliferation of CD4+ and CD8+ effector T cells are not affected.  RGI-6004 has minimal impact on platelets (counts and degranulation), minimal binding to major immune cells, nor observable impact on hematological profile of normal human blood.  In cynomolgus monkey, its t1/2 is shown to be ~10 days, while its clinical hematology, coagulation, blood chemistry, immunophenotyping in peripheral blood, serum cytokine analysis, and pathology, does not demonstrate safety alarms. In sum, the behavior of RGI-6004 highlights the potential as a next-generation Treg-depleting agent in cancer immunotherapy.

AB08-H1, A humanized antibody that directly kills cancer target cells without ADCC and CDC. AB08-H1 is a humanized IgG that specifically targets pan MHC II (synonym for HLA II, human leukocyte antigen). Upon binding to the cell surface MHC class II molecule, the antibody induces homotypic aggregation, lysosomal membrane permeabilization, and ultimately cell lysis of the target malignant cells directly without the involvement of ADCC and CDC.  REGiMMUNE overcame the original bottleneck of protein production of the humanized IgG, developed a high yield method to manufacture it in mammalian cells.  As MHC Class II molecules are found highly expressed on lymphoid malignant cells, and have been increasingly recognized to express highly in major solid cancer cells, AB08-H1 is expected to treat various types of lymphoid malignancies (Hodgkin and Non-Hodgkin lymphomas), and solid cancers.

REGiMMUNE is encouraged by the recent news of Nobel Prize in Physiology granted to Dr. Shimon Sakaguchi and others, for their works on Treg cells.  We are pleased to see that the fundamental roles of Treg cells in autoimmune disease, GvHD, cancer, and infectious disease are recognized in highest profile.  REGiMMUNE is committed to developing therapeutics with, as Dr. Shimon Sakaguchi well put it, Treg-up strategies vs Treg-down strategies.

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About REGiMMUNE Limited

REGiMMUNE is a clinical-stage biopharmaceutical company focused on creating innovative immunotherapies by harnessing the power of regulatory T cells (Treg). REGiMMUNE is creating a pipeline of novel product candidates that either enhances Treg activities for immune disease, or suppresses Treg activities for cancer and infectious disease.

REGiMMUNE’s proprietary platform technology, reVax, induces immune tolerance in an antigen-specific manner through pharmacological induction of Treg cells. RGI-2001, a first-in-class Treg-inducing agent, has been developed to enhance Treg cell activities for Graft vs Host Disease (GvHD) in bone marrow transplantation and potentially for solid organ transplantation.  RGI-2001 completed Phase IIb clinical trial in the US.

REGiMMUNE has also developed antibody therapeutics to suppress Treg activities either by depleting activated Treg cells or by silencing immune suppressive signaling of activated Treg cells. RGI-6004 has been developed to target highly selectively activated tumor infiltrating Treg cells while leaving other T effector cells and naïve Treg cells functionally intact. Treg-mediated immune suppression has been indicated to play a critical role in solid tumors (eg. melanoma and lung cancer) and chronic infections (eg. hepatitis B and C).

 

Corporate Contact

Steve Yang
Chief Operating Officer (COO)
REGiMMUNE Limited
+886 2 2555 3377 #511
stevey@regimmune.com

 

 

REGiMMUNE於日本京都舉辦的「Antibody Engineering & Therapeutics Asia 2025」發表抗體新藥研發成果

2025年10月30日，台北 – 瑞格國際生技股份有限公司（REGiMMUNE），一家位於臨床階段的新藥開發公司，致力於調節性T細胞（Treg）免疫治療領域和癌症新型療法，加速推進其 Treg 誘導新藥 RGI-2001 於移植物抗宿主疾病（GvHD）之後期臨床開發。同時，基於多年免疫學與 Treg 相關研究成果，瑞格亦積極布局腫瘤免疫抗體產品線。公司於10月20日至22日在日本京都舉行之 Antibody Engineering & Therapeutics Asia 2025 年會中發表其抗體新藥計畫之最新臨床前數據。

瑞格目前正推進其Treg誘導新藥RGI-2001於移植併發症（移植物抗宿主疾病，GvHD）之後期臨床開發，同時憑藉多年在人體免疫學及Treg細胞領域的深厚研究實力，積極拓展公司之抗體治療產品線。其中包含選擇性清除腫瘤浸潤Treg細胞（Treg depletion）的RGI-6004及抑制Treg活性（Treg suppression）的AB01，此外亦包含鎖定血液與實體腫瘤共同標記之抗體AB08-H1。此次於京都的報告著重於介紹RGI-6004與AB08-H1。

RGI-6004：選擇性清除活化Treg細胞之去岩藻糖化抗體

RGI-6004為完全人源化IgG1抗體，可鎖定GARP/Latent-TGFβ1複合體，設計目的在於選擇性清除腫瘤微環境中之活化Treg細胞，藉以減緩腫瘤免疫抑制並增強抗腫瘤免疫反應。

研究顯示，RGI-6004能以高親和力結合活化Treg細胞，而不影響非活化Treg細胞及CD4+、CD8+效應T細胞，並可辨識臨床實體腫瘤組織中的腫瘤浸潤Treg細胞。其去岩藻糖化版本可高度選擇性地清除活化Treg細胞，效力可達約10 pM，同時不影響CD4+與CD8+效應T細胞之顆粒酶B誘導或增殖反應。

RGI-6004對血小板（數量及去顆粒作用）影響極低，亦對主要免疫細胞無顯著結合，於正常人類血液之血液學指標亦無異常；在食蟹猴試驗中，其半衰期約為10天，臨床生化、凝血、血液分析、免疫表型、細胞激素與病理數據均未顯示安全性疑慮。

綜合上述結果，RGI-6004展現成為下一代Treg清除型癌症免疫療法的潛力。

AB08-H1：無需ADCC或CDC、可直接殺死癌細胞的人源化抗體

AB08-H1為可專一性鎖定泛MHC II（亦稱HLA II）的人源化IgG抗體。抗體與癌細胞表面MHC II分子結合後，可誘導細胞間同源聚集、溶酶體膜通透化並直接導致癌細胞裂解，而非透過ADCC或CDC機制殺傷。

瑞格已成功克服人源化IgG過去在蛋白質產量上的製程瓶頸，並建立高產率哺乳動物細胞生產方式。由於MHC II分子在淋巴性腫瘤細胞上高度表現，且研究顯示在多種實體癌中亦有顯著表現，AB08-H1預期可用於治療多類淋巴瘤（含霍奇金及非霍奇金淋巴瘤）及各類實體癌。

瑞格對近期諾貝爾生理或醫學獎頒發給坂口志文教授及其團隊，表彰其在調節性T細胞（Treg）領域的研究成果，深感振奮。我們非常欣喜地看到，Treg細胞在自體免疫疾病、移植物抗宿主疾病（GvHD）、癌症及感染性疾病中的關鍵角色，獲得全球最高榮譽的肯定。

瑞格將持續致力於開發以Treg為核心的治療方式，正如坂口志文教授所強調的，透過「提升Treg（Treg-up）」以及「抑制Treg（Treg-down）」策略，開創免疫醫學新境界。

本文結束

 

關於瑞格

瑞格是一家位於臨床階段的生技公司，致力於透過調控調節性T細胞（Treg）之免疫機制，開發創新免疫療法。公司的產品線涵蓋可提升Treg活性之免疫疾病治療，以及抑制Treg活性之癌症與感染疾病治療。

瑞格擁有專屬平台技術 reVax，可藉由藥物方式誘導Treg細胞，達到抗原特異性的免疫耐受。其領先產品 RGI-2001 為首創Treg誘導劑，用以提升Treg活性改善骨髓移植後GvHD，並具發展至實體器官移植之潛力，已完成美國Phase IIb臨床試驗。

公司亦已開發具Treg抑制作用之抗體療法，透過選擇性去除活化Treg或抑制其免疫抑制訊號。RGI-6004 可選擇性鎖定腫瘤浸潤活化Treg細胞，而不影響其他效應T細胞及初始Treg細胞功能。研究指出，Treg介導免疫抑制在多種實體癌症及慢性感染中扮演關鍵角色。

 

媒體聯絡人

楊思聖 (Steve Yang)
營運長
瑞格國際生技股份有限公司
+886 2 2555 3377 #511
stevey@regimmune.com