Beyond Conventional Anti-TIGIT: HanchorBio Secures Taiwan TFDA Approval for HCB303 Following U.S. FDA Clearance
Differentiated trispecific TIGIT-Fc ligand-trap strategy aims to address CD226 downregulation, a potential limitation of conventional anti-TIGIT antibodies
U.S FDA clearance followed by accelerated Taiwan TFDA approval advances HCB303 toward multi-regional Phase 1 clinical development
[Taipei, Shanghai, San Francisco | October 30, 2026] – HanchorBio, Inc. (TWSE: 7827), a global clinical-stage biotechnology company developing next-generation immunotherapies for oncology and immune-mediated diseases, today announced that its wholly owned subsidiary, FBD Biologics Limited, has received approval from the Taiwan Food and Drug Administration (TFDA) for the Investigational New Drug (IND) application for HCB303, a next-generation trispecific fusion protein featuring a differentiated TIGIT-Fc ligand-trap strategy.
The TFDA approval follows U.S. FDA IND clearance on October 2, 2026 (U.S. time), establishing regulatory authorization in both jurisdictions for HCB303’s planned clinical investigation.
Unlike conventional anti-TIGIT antibodies that primarily act by blocking inhibitory signaling through the TIGIT receptor, HCB303 employs a differentiated TIGIT-Fc ligand-trap strategy designed to bind multiple TIGIT-associated ligands, including PVR/CD155 and CD112, potentially limiting ligand- mediated CD226 downregulation. Combined with PD-L1 blockade and SIRPα-mediated CD47 checkpoint inhibition, HCB303 aims to coordinate innate and adaptive antitumor immunity within a single engineered molecule.
“The future of immunotherapy will not be defined simply by adding more targets, but by understanding how those targets interact,” said Scott Liu, Ph.D., Founder and Chairman of HanchorBio. “HCB303 represents that philosophy. Conventional anti-TIGIT antibodies block the receptor but leave shared ligands available to engage CD226, potentially contributing to its downregulation. We therefore designed a differentiated ligand-trap strategy intended to modulate inhibitory immune signaling while potentially reducing CD226 receptor downregulation and exploring the preservation of its immune-activating function. With U.S. FDA clearance followed by Taiwan TFDA approval, we are advancing this biology into globally coordinated clinical development. This is precisely the type of differentiated therapeutic architecture our FBDB™ platform was built to deliver.”
Beyond Conventional Anti-TIGIT: Addressing the CD226 Challenge
Despite substantial interest in TIGIT-targeted cancer immunotherapy, disappointing results from several late-stage anti-TIGIT antibody trials have highlighted the pathway’s complexity and the importance of maintaining activating immune signals.
TIGIT and CD226 are functionally interconnected receptors on T cells and natural killer (NK) cells. CD226 is an important activating receptor that shares ligands, including PVR/CD155 and CD112, with the inhibitory receptor TIGIT. Conventional anti-TIGIT antibodies block inhibitory TIGIT signaling but do not directly prevent shared ligands, including PVR/CD155 and CD112, from engaging CD226. However, sustained CD155 engagement can contribute to CD226 internalization and downregulation, potentially limiting immune activation.
HCB303 takes a different molecular design approach. Its TIGIT-Fc ligand-trap architecture is designed to bind shared ligands, including PVR/CD155 and CD112, with the aim of reducing ligand-mediated CD226 receptor internalization and downregulation, thereby potentially preserving CD226 cell-surface expression. However, whether preservation of receptor expression can further support CD226-mediated immune-activating signaling and translate into meaningful antitumor activity and clinical benefit remains to be established through subsequent clinical and translational studies.
HCB303 also integrates PD-L1 blockade and SIRPα-mediated CD47 checkpoint inhibition, aiming to coordinate macrophage, T-cell, and NK-cell antitumor responses within a single trispecific fusion protein.
Taiwan’s Accelerated Regulatory Pathway Advances HCB303’s Global Development
HCB303 received TFDA approval through Taiwan’s accelerated review pathway for multinational, multicenter clinical trials. Introduced in September 2025, the streamlined procedure provides a 15-day review process for eligible applications, facilitating more efficient international clinical development.
In August 2026, TFDA further simplified regulatory submission requirements for qualifying first-in-human studies, including removing the requirement to submit foreign participating hospitals’ institutional review board approval letters under applicable conditions.
HCB303’s progression from U.S. FDA IND clearance to accelerated Taiwan TFDA approval highlights HanchorBio’s globally coordinated regulatory strategy, enabling more efficient advancement of differentiated immunotherapies into multinational clinical development.
From Differentiated Biology to Global Clinical Evidence
HanchorBio is preparing to advance HCB303 into its Phase 1 first-in-human, dose-escalation study (HCB303-ONC-101; NCT07859228) in patients with advanced, relapsed, or refractory solid tumors who have exhausted appropriate standard treatment options.
The study will evaluate safety, tolerability, pharmacokinetics, pharmacodynamics, immunogenicity, biomarkers, and preliminary antitumor activity. Translational assessments will investigate target engagement, immune modulation, and exposure-response relationships to inform dose optimization and subsequent clinical development.
These translational studies will also assess biomarkers related to CD226 receptor expression, TIGIT-associated ligands, and myeloid immune cells to explore how HCB303 modulates different immune cell populations and signaling pathways, and to evaluate whether its differentiated molecular design produces the intended biological effects in patients.
“The history of TIGIT drug development reminds us that a compelling story does not automatically translate into clinical benefit,” said Alvin Luk, Ph.D., M.B.A., C.C.R.A., President and Chief Medical Officer (Group) and CEO (USA) of HanchorBio. “The challenge now is to determine whether HCB303’s differentiated mechanism translates into meaningful activity in patients. Our Phase 1 study goes beyond conventional dose escalation by integrating clinical pharmacology, target engagement, immune biomarkers, and early antitumor activity. We need to understand not just HCB303’s safety and pharmacology, but whether we see evidence of its intended biological effects, at what exposure, and in which patients it may offer the greatest potential benefit. That evidence will determine our next clinical development decisions.”
Clinical trial initiation and patient enrollment will proceed in accordance with applicable regulatory requirements, institutional ethics approval, and clinical site readiness.
FBDB™ Platform: Expanding Differentiated Trispecific Therapeutics
HCB303 is HanchorBio’s second FBDB™-derived trispecific immunotherapy to advance toward human clinical evaluation, following HCB301. While HCB301 integrates SIRPα, PD-L1, and TGF-β biology, HCB303 incorporates a distinct TIGIT-Fc ligand-trap strategy alongside SIRPα and PD-L1 modulation, illustrating the platform’s versatility in generating differentiated multispecific therapeutic architectures.
About HCB303
HCB303 is an investigational, humanized trispecific fusion protein developed using HanchorBio’s proprietary FBDB™ platform. It is designed to simultaneously modulate the SIRPα/CD47, PD-L1/PD-1, and TIGIT/PVR immune pathways, integrating macrophage, T-cell, and NK-cell antitumor immunity within a single engineered molecule. HCB303 is being developed as a potential treatment for advanced solid tumors. Its safety and efficacy have not been established.
About HanchorBio
HanchorBio (TWSE: 7827) is a global clinical-stage biotechnology company focused on inventing and developing next-generation biologics for cancer and immune-mediated diseases using its proprietary FBDB™ platform.
HanchorBio’s pipeline includes HCB101, its lead SIRPα-based innate immune checkpoint program; HCB301, a clinical-stage trispecific immunotherapy targeting SIRPα, PD-L1, and TGF-β biology; HCB303, a clinical-stage trispecific immunotherapy integrating SIRPα/CD47, PD-L1/PD-1, and TIGIT/PVR biology; and additional programs across oncology and immune-mediated diseases. For more information, please visit: https://www.HanchorBio.com.
Forward-Looking Statements
This press release contains forward-looking statements regarding the clinical development of HCB303; the timing, initiation, design, conduct, and potential outcomes of future clinical studies; HCB303’s proposed mechanisms, therapeutic characteristics, safety, and antitumor activity; potential preservation of CD226 expression or signaling; HanchorBio’s global development strategy; and the capabilities and potential of the FBDB™ platform. These statements are based on current expectations and assumptions and involve risks and uncertainties that could cause actual results to differ materially from those described. U.S. FDA clearance and Taiwan TFDA approval authorize clinical investigation in accordance with applicable requirements but do not constitute marketing approval or establish the safety or efficacy of HCB303. Mechanistic hypotheses and preclinical observations may not translate into clinical benefit. There can be no assurance regarding the timing or success of clinical development or future regulatory approvals. HanchorBio undertakes no obligation to update forward-looking statements except as required by applicable law.
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漢康生技 HCB303 採差異化 TIGIT-Fc 策略 繼美國 FDA 後再獲台灣 TFDA 核准臨床試驗
創新三特異性 TIGIT-Fc 配體捕捉策略，旨在克服傳統抗 TIGIT 抗體對 CD226 訊號調節的潛在限制
繼美國 FDA 同意進行臨床試驗後，HCB303 再透過台灣 TFDA 加速審查取得核准，推進跨國第一期臨床開發
【台北、上海、舊金山，2026 年 10 月 30日】－全球臨床階段生技公司漢康生技（TWSE：7827），致力於開發應用於腫瘤及免疫介導疾病的次世代免疫療法，今日宣布，旗下全資子公司 FBD Biologics Limited 自主研發的次世代三特異性融合蛋白候選藥物 HCB303，已獲台灣衛生福利部食品藥物管理署（TFDA）核准新藥臨床試驗申請（IND）。HCB303 採用具差異化特色的 TIGIT-Fc 配體捕捉（ligand-trap）策略，探索多重免疫調節機制於實體腫瘤治療的應用潛力。
繼 HCB303 於 2026 年 10 月 2 日（美國時間）獲美國食品藥物管理局（FDA）同意進行臨床試驗後，本次台灣 TFDA 核准，使 HCB303 取得美台兩地進行臨床研究的許可，支持後續跨國臨床開發。
相較於傳統抗TIGIT抗體主要透過阻斷TIGIT受體的抑制性訊號發揮作用，HCB303採用差異化TIGIT-Fc配體捕捉（ligand-trap）策略，旨在結合PVR/CD155及CD112等多種TIGIT相關配體，以期減少配體介導的CD226受體表現下調。結合PD-L1阻斷及SIRPα介導的CD47免疫檢查點抑制作用，HCB303期望透過單一工程化分子，協同調節先天性與適應性抗腫瘤免疫反應。
漢康生技創辦人暨董事長劉世高博士表示：「未來免疫療法的發展，關鍵不僅在於增加作用標的，更在於深入理解不同免疫標的之間的交互作用，而 HCB303 正體現這項研發理念。傳統抗 TIGIT 抗體雖可阻斷 TIGIT 受體，但共享配體仍可與 CD226 結合，可能進一步導致 CD226 表現下調。
我們因此設計差異化的配體捕捉策略，期望在調節免疫抑制訊號的同時，減少CD226受體表現下調，並探索維持其免疫活化功能的潛力。
隨著 HCB303 先後取得美國 FDA 與台灣 TFDA 的臨床試驗許可，我們正將這項創新免疫生物學策略推進至全球協同的臨床開發，這也正是 FBDB™ 平台所致力實現的差異化藥物設計方向。」
超越傳統抗 TIGIT 策略：探索 CD226 訊號調節的關鍵挑戰
TIGIT 免疫調節路徑近年受到癌症免疫治療領域廣泛關注，但多項抗 TIGIT 抗體後期臨床試驗未達預期結果，也凸顯此免疫路徑的複雜性，以及維持免疫活化訊號的重要性。
TIGIT 與 CD226 是存在於 T 細胞及自然殺手細胞（NK cell）表面的兩種功能相互關聯的受體。其中，CD226 為重要的免疫活化受體，與具有抑制作用的 TIGIT 共享包括 PVR/CD155 及 CD112 在內的配體。
傳統抗 TIGIT 抗體主要透過阻斷 TIGIT 受體的抑制性訊號發揮作用，但 PVR/CD155、CD112 等共享配體仍可與 CD226 產生交互作用。然而，持續性的配體與受體作用也可能造成 CD226 內吞及表現下調，進而限制免疫活化訊號的持續性。
HCB303則採取不同的分子設計策略。其TIGIT-Fc配體捕捉架構旨在結合PVR/CD155及CD112等共享配體，以期減少配體介導的CD226受體內吞及表現下調，進而維持CD226受體的表面表現。然而，維持受體表現是否能進一步支持CD226介導的免疫活化訊號，並轉化為實際抗腫瘤活性及臨床受益，仍有待後續臨床與轉譯研究驗證。
此外，HCB303 亦整合 PD-L1 阻斷及 SIRPα 介導的 CD47 免疫檢查點抑制機制，期望透過單一三特異性融合蛋白，同時協調巨噬細胞、T 細胞及 NK 細胞的抗腫瘤免疫作用。
台灣加速審查機制支持 HCB303 全球臨床開發
HCB303 透過台灣針對跨國多中心臨床試驗的加速審查機制取得 TFDA 核准。該機制於 2025 年 9 月推出，符合資格的申請案件可適用 15 天審查程序，有助於提升跨國臨床試驗的審查效率。
2026 年 8 月，TFDA 進一步簡化符合條件的首次人體臨床試驗申請要求，包括在適用條件下，免除提交海外參與醫院人體研究倫理審查委員會（IRB）核准文件的要求。
HCB303 從美國 FDA 同意進行臨床試驗，到透過台灣 TFDA 加速審查取得核准，展現漢康生技跨國協同的法規與臨床開發策略，並有助於更有效率地推進差異化免疫治療候選藥物的國際臨床研究。
從差異化免疫機制到全球臨床證據
漢康生技正規劃推進 HCB303 第一期首次人體劑量遞增臨床試驗（HCB303-ONC-101；NCT07859228），預計納入晚期、復發或難治性，且已無其他合適標準治療選擇的實體腫瘤病人。
該試驗將評估 HCB303 的安全性、耐受性、藥物動力學、藥效學、免疫原性、生物標誌物及初步抗腫瘤活性。同時，試驗也將透過轉譯研究分析標靶結合、免疫調節作用，以及藥物暴露量與反應之間的關係，作為後續劑量優化與臨床開發策略的重要依據。
相關轉譯研究亦將關注CD226受體表現、TIGIT相關配體及髓系免疫細胞等生物標誌物，以探索HCB303對不同免疫細胞與訊號路徑的調節作用，並評估其差異化分子設計能否在人體中產生預期的生物學反應。
漢康生技總裁暨集團醫療長、美國子公司執行長陸英明博士表示：「TIGIT 藥物的研發歷程提醒我們，具吸引力的科學理論不一定能轉化為實際臨床受益。目前最重要的課題，是確認 HCB303 的差異化作用機制能否在病人體內產生具有臨床意義的活性。我們的第一期臨床試驗不僅著重傳統劑量遞增評估，也將整合臨床藥理學、標靶結合、免疫生物標誌物及初步抗腫瘤活性等研究。我們不只需要了解 HCB303 的安全性與藥理特性，更希望確認其是否產生預期的生物學作用、在何種藥物暴露量下產生反應，以及哪些病人可能具有較高的潛在受益。這些臨床證據將成為後續開發決策的關鍵依據。」
後續臨床試驗啟動與病人收案，將依據適用法規要求，並於完成必要的機構倫理審查及試驗中心準備程序後推進。
FBDB™ 平台持續拓展差異化三特異性免疫療法
繼 HCB301 之後，HCB303 為漢康生技透過 FBDB™ 平台開發、第二款推進人體臨床評估的三特異性免疫治療候選藥物。
HCB301 整合 SIRPα、PD-L1 及 TGF-β 生物學機制；HCB303 則在 SIRPα 與 PD-L1 免疫調節架構上，導入差異化 TIGIT-Fc 配體捕捉策略，展現 FBDB™ 平台整合不同免疫機制、開發多特異性融合蛋白藥物的延展性。
關於 HCB303
HCB303是漢康生技運用自主開發FBDB™平台所開發的試驗性人源化三特異性融合蛋白，旨在同步調控SIRPα/CD47、PD-L1/PD-1及TIGIT/PVR三條免疫路徑，透過單一工程化分子整合巨噬細胞、T 細胞與自然殺手細胞（NK cell）的抗腫瘤免疫作用。
HCB303 正開發作為晚期實體腫瘤的潛在治療選擇，其安全性及療效尚未獲得證實。
關於漢康生技
漢康生技（TWSE：7827）為全球臨床階段生技公司，運用自主開發的FBDB™平台，專注於癌症及免疫介導疾病之下一代生物藥的創新與開發。
漢康生技產品管線包括：以SIRPα為基礎、靶向先天免疫檢查點的核心候選藥物HCB101；已進入臨床階段、靶向SIRPα、PD-L1 及TGF-β生物學機制的三特異性免疫療法HCB301；整合SIRPα/CD47、PD-L1/PD-1 及TIGIT/PVR 生物學機制的臨床階段三特異性免疫療法 HCB303；以及其他涵蓋癌症與免疫介導疾病的研發項目。
前瞻性聲明
本新聞稿包含前瞻性聲明，包括有關 HCB303 的臨床開發；未來臨床研究的時程、啟動、設計、執行及潛在結果；HCB303 預期的作用機制、治療特性、安全性及抗腫瘤活性；保留 CD226 表現或訊號傳遞的潛在可能性；漢康生技的全球開發策略；以及 FBDB™ 平台的能力與潛力等相關陳述。
此類聲明係基於目前的預期與假設，並涉及可能導致實際結果與所述內容存在重大差異的風險與不確定性。美國 FDA 同意及台灣 TFDA 核准 HCB303 進行臨床研究，均須遵循適用法規要求，並不代表取得上市許可，亦不代表其安全性或療效已獲證實。相關作用機制假說及臨床前觀察結果未必能轉化為實際臨床受益，且無法保證臨床開發或未來法規核准的時程與成功。除適用法律另有規定外，漢康生技無義務更新任何前瞻性聲明。