Bexobrutideg

Orphan Drug Designation follows positive Phase 1 data presented at the 12th International Workshop on Waldenström Macroglobulinemia First-in-class Bruton’s tyrosine kinase (BTK) degrader NX-5948 assigned nonproprietary name “bexobrutideg” in newly named degrader class of drugs March 17, 2025 -- Nurix Therapeutics, Inc. (Nasdaq: NRIX), a clinical-stage biopharmaceutical company focused on the discovery, development and commercialization of targeted protein degradation medicines, today announced that the U.S. Food and Drug Administration (FDA) has granted Orphan Drug Designation (ODD) to bexobrutideg (NX-5948) for the treatment of Waldenström macroglobulinemia (WM). Bexobrutideg is an orally bioavailable, brain penetrant degrader of BTK which is being evaluated in an ongoing Phase 1a/b clinical trial in adults with relapsed or refractory B-cell malignancies. The FDA's Orphan Drug Designation program provides orphan status to therapies intended for the treatment, diagnosis, or prevention of rare diseases that affect fewer than 200,000 people in the United States. This designation provides certain benefits, including tax credits for qualified clinical testing, waiver or partial payment of FDA application fees and seven years of market exclusivity, if approved. “The FDA’s Orphan Drug Designation for bexobrutideg, also known as NX-5948, represents an important milestone in our regulatory strategy and underscores the significant unmet medical need for improved treatments for Waldenström macroglobulinemia,” said Arthur T. Sands, M.D., Ph.D., president and chief executive officer of Nurix. “Granting of the designation highlights bexobrutideg’s potential to provide patients with WM a promising new therapeutic option. We are also pleased to announce that our investigational therapy bexobrutideg has been assigned a nonproprietary name reflecting its novel mechanism of action, designated with the unique suffix “deg” for degrader.” In collaboration with the national naming authority, United States Adopted Name (USAN) Council, Nurix’s lead BTK degrader, NX-5948, was assigned the nonproprietary name “bexobrutideg.” The U.S. and international drug naming convention is designed to select a single name of worldwide acceptability for each active substance that is intended to be marketed as a pharmaceutical. Most notable with bexobrutideg is the designation of a new suffix, “deg,” which references bexobrutideg’s novel degradation mode of action. Targeted protein degraders are characterized by their bifunctional nature, binding to both a target protein and a ligase to drive ubiquitination and catalytic degradation of the target through the proteasome. The new deg suffix is an important recognition that the mechanism of action, pharmacokinetics and pharmacodynamics of targeted protein degraders are fundamentally different than inhibitors, which all use the “ib” suffix. The central stem of the name, “bruti,” references the target, Bruton’s tyrosine kinase (as used in ibrutinib, zanubrutinib and acalabrutinib). The prefix “bexo” is the unique identifier of a specific agent in the class and is often used for ease of reference to the agent. “We are excited that bexobrutideg has been recognized by the USAN Council as a unique entity and member of a new class of small molecule drugs, targeted protein degraders,” said Gwenn Hansen, Ph.D., chief scientific officer of Nurix. “The catalytic mechanism of action and event driven pharmacology triggering ubiquitination and proteasomal degradation of a target protein is highly differentiated from inhibitors and allows degraders to eliminate the totality of a protein’s function. In our BTK degrader clinical program, we have also established that degraders can eliminate mutant oncoproteins that have proven to be resistant to inhibitor therapy.” Bexobrutideg is an investigational, orally bioavailable, brain penetrant, small molecule degrader of BTK that is currently being evaluated in a Phase 1 clinical trial in patients with relapsed or refractory B cell malignancies. Nurix has previously reported encouraging safety and efficacy data in patients with WM treated in the ongoing Phase 1a/b clinical trial of bexobrutideg demonstrating early promise of clinical benefit with potential for durable outcomes. Nurix continues to enroll patients with WM in an ongoing Phase 1b expansion cohort and anticipates sharing additional clinical data in 2025. Additional information on the ongoing clinical trial can be accessed at clinicaltrials.gov (NCT05131022). Nurix is also developing bexobrutideg for the potential treatment of inflammatory diseases. WM is a rare, slow growing type of non-Hodgkin’s lymphoma that is characterized by the replacement of normal bone marrow cells by malignant lymphocytic cells that produce monoclonal IgM. This replacement leads to anemia, bleeding, and impaired immune function, while the elevated IgM levels may cause neurologic symptoms. The incidence of Waldenström macroglobulinemia ranges from 0.361,2 to 0.573 per 100,000 people in the United States or approximately 1,200 to 1,900 annually. With a median disease duration approaching 10 years, 4 approximately 12,000 to 19,000 patients are living with Waldenstrom’s macroglobulinemia in the United States. Recommended first-line treatments including chemoimmunotherapy and BTK inhibitor (BTKi) therapy. There are no therapies approved to treat WM patients after a BTKi. Nurix Therapeutics is a clinical stage biopharmaceutical company focused on the discovery, development and commercialization of targeted protein degradation medicines, the next frontier in innovative drug design aimed at improving treatment options for patients with cancer and inflammatory diseases. Nurix’s wholly owned, clinical stage pipeline includes degraders of Bruton’s tyrosine kinase (BTK), a B-cell signaling protein, and inhibitors of Casitas B-lineage lymphoma proto-oncogene B (CBL-B), an E3 ligase that regulates activation of multiple immune cell types including T cells and NK cells. Nurix also is advancing multiple potentially first-in-class or best-in-class degraders and degrader antibody conjugates (DACs) in its preclinical pipeline. Nurix’s partnered drug discovery pipeline consists of preclinical stage degraders of IRAK4 and STAT6, as well as multiple additional programs under collaboration agreements with Gilead Sciences, Inc., Sanofi S.A. and Pfizer Inc., within which Nurix retains certain options for co-development, co-commercialization and profit sharing in the United States for multiple drug candidates. Powered by a fully AI-integrated discovery engine capable of tackling any protein class, and coupled with unparalleled ligase expertise, Nurix’s dedicated team has built a formidable advantage in translating the science of targeted protein degradation into clinical advancements. Nurix aims to establish degrader-based treatments at the forefront of patient care, writing medicine’s next chapter with a new script to outmatch disease. Nurix is headquartered in San Francisco, California. For additional information visit http://www.nurixtx.com. The content above comes from the network. if any infringement，please contact us to modify.

▎药明康德内容团队编辑 编者按：今日，Arvinas和辉瑞（Pfizer）公司联合宣布其明星PROTAC分子vepdegestrant的首个关键3期临床试验结果，并指出这款药物是首个在3期试验中展现出临床获益的PROTAC分子。这些数据将与全球监管机构分享，支持潜在的监管申请递交。值得一提的是，近10年前，在此类技术刚刚起步之时，药明康德就开始布局相关的能力和技术，并积累了大量成功经验。随着近年来对PROTAC了解的逐步深入，公司针对这类创新分子已搭建了完善的一体化赋能平台，集发现、合成、分析纯化和测试等能力于一体，目前已成功支持超过100款PROTAC分子的开发，其中超过20个分子顺利推进至临床阶段。今天这篇文章里，药明康德内容团队将从vepdegestrant的最新临床结果出发，与读者分享PROTAC药物的研发历史与未来的潜在进展。 最新3期试验数据如何？ Vepdegestrant是一款潜在“first-in-class”的口服PROTAC降解剂，利用人体天然的蛋白质降解系统特异性地靶向并降解雌激素受体（ER）。它已经获得美国FDA授予的突破性疗法认定，用于治疗经治ER阳性、HER2阴性乳腺癌。在这项名为VERITAC-2的临床试验中，在携带ESR1突变的激素受体（HR）阳性、HER2阴性乳腺癌患者群体中，vepdegestrant与活性对照相比，为患者的无进展生存期（PFS）带来统计显著并具有临床意义的改善。这些患者在此前接受CDK4/6抑制剂和内分泌治疗后疾病出现进展。在携带ESR1突变的患者群体中，患者的疾病进展或死亡风险降低超过40%（风险比低于0.60）。在包含未携带ESR1突变患者的意向治疗（ITT）患者群体中，PFS的改善未达到统计显著标准。 次要终点总生存期（OS）数据目前尚不成熟，仍需要研究继续评估。VERITAC-2的详细结果将在今年晚些时候的医学会议上报告，这些数据将与全球监管机构分享，潜在支持递交监管申请。 “PROTAC降解剂的首个3期数据的发布是一项重大成就。这些数据表明，vepdegestrant有望为数以千计患有转移性乳腺癌且肿瘤携带1型雌激素受体（ER1）突变的患者带来临床上具有意义的疗效，”Arvinas董事长、首席执行官兼总裁John Houston博士表示。“我们要感谢参与此次试验的患者和研究者，并期待与监管机构分享这些数据，我们也将在2025年的医学会议上进一步展示这一成果。” PROTAC演化史 说到PROTAC分子的历史，还要追溯到Arvinas公司的联合创始人，耶鲁大学的Craig Crews教授，在2001年发表的一篇具有里程碑意义的论文。研究人员设计了一种人造双功能性分子，它的一端能够结合目标蛋白，另一端则是能结合E3连接酶的多肽。研究发现，这种分子能将目标蛋白拉到E3连接酶附近，让E3连接酶给目标蛋白打上泛素标签，标记它们送入细胞的蛋白酶体系统进行降解。 “未来，这一方法有望用于让蛋白出现有条件失活，以及降解导致疾病的蛋白。”该论文的摘要里写道。这一分子也被命名为蛋白靶向嵌合分子-1（protein-targeting chimeric molecule 1），缩写为Protac-1。 在2008年，Crews教授团队的科学家更近一步，开发出一种双功能小分子药物。这款小分子的一端可选择性结合雄激素受体，另一端结合叫做MDM2的E3连接酶。这种能够靶向蛋白进行降解的双功能分子也被命名为PROTAC（PROteolysis TArgeting Chimera）。我们如今常用来指代靶向蛋白降解疗法的“PROTAC”正是由此而来。 2013年，Crews教授联合创办了Arvinas公司，加速推进这一技术的科学转化。为了测试此类分子的成药可行性，该公司优先选择雄激素受体和雌激素受体这两个比较成熟的靶点。其中靶向雌激素受体的PROTAC分子，就是今日在3期临床试验中展现出临床获益的vepdegestrant（曾名为ARV-471）。由于它在前期临床试验中表现出选择性降解野生型和突变型雌激素受体的出色能力，辉瑞公司在2021年与Arvinas达成超20亿美元的研发合作，共同打造这款PROTAC分子成为治疗ER阳性乳腺癌患者的支柱性内分泌疗法。 除了vepdegestrant之外，Arvinas公司的其他PROTAC降解剂也取得了显著进展。去年，Arvinas与诺华（Novartis）就其针对雄激素受体的第二代PROTAC降解剂ARV-766达成了超过10亿美元的研发合作协议。此外，Arvinas针对LRRK2的蛋白降解剂ARV-102已进入1期临床试验，旨在治疗帕金森病。 新靶点、新模式，靶向蛋白降解走向多元化 Arvinas之外，还有多家公司正在开发与PROTAC分子具有类似作用机制的新药。例如，Kymera Therapeutics公司和赛诺菲（Sanofi）联合开发的IRAK4靶向蛋白降解剂KT-474（SAR444656）已处于2期临床开发阶段，用于治疗化脓性汗腺炎（HS）和特应性皮炎（AD）。该公司靶向STAT6的蛋白降解剂KT-621处于1期临床开发阶段，潜在治疗与2型炎症相关的多种免疫和炎症性疾病。 Nurix Therapeutics公司可穿越血脑屏障的布鲁顿氏酪氨酸激酶（BTK）蛋白降解剂NX-5948目前处于1b/2期临床开发阶段，去年公布的早期临床试验数据显示，在治疗复发/难治性华氏巨球蛋白血症（WM）患者时，NX-5948达到77.8%的客观缓解率，其中两例患者已接受治疗超过1年。该公司的另一款蛋白降解剂NX-2127可同时降解BTK和IKZF蛋白，已进入治疗B细胞恶性肿瘤的首个人体临床试验。 PROTAC分子之外，基于诱导接近（induced proximity）的创新蛋白降解模式也不断涌现。分子胶蛋白降解剂领域近两年来得到多家大型药企的关注。诺华（Novartis）、渤健（Biogen）、辉瑞、艾伯维（AbbVie）、武田（Takeda）、卫材（Eisai）与诺和诺德（Novo Nordisk）等公司纷纷达成分子胶相关的研发合作。 专注于蛋白降解的新锐持续涌现，也进一步扩展了创新蛋白降解模式。例如，Pinetree Therapeutics开发多特异性靶向蛋白质降解剂，A轮融资1700万美元，且与阿斯利康（AstraZeneca）达成总额超5亿美元合作；Draupnir Bio和Booster Therapeutics基于溶酶体机制开发蛋白降解剂，种子轮融资逾千万美元；Firefly Bio由诺贝尔化学奖得主Carolyn Bertozzi教授联合创立，开发蛋白降解剂-抗体偶联药物（DAC）。Bertozzi教授联合创建的Lycia Therapeutics在去年也完成超1亿美元的C轮融资，推进其可降解细胞外和细胞膜蛋白的溶酶体靶向嵌合体（LYTAC）技术进入临床开发。 此外，Automera公司则致力于开发自噬靶向嵌合小分子（AUTACs）。Expansion Therapeutics开发的核糖核酸酶靶向嵌合体（RIBOTAC）技术，可以实现对特定RNA的靶向降解。Vicinitas则是一家针对癌症与遗传疾病，以专有靶向蛋白稳定平台开发创新疗法的公司，其靶向去泛素化酶嵌合体（DUBTAC）平台生成的小分子可以促进蛋白质上的泛素链移除，进而避免蛋白质的降解。 ▲药明康德快速构建双功能性降解剂的平台能力 作为业内靶向蛋白降解药物开发的重要赋能平台之一，药明康德早在此类药物的浪潮刚刚兴起之际，就快速搭建了综合性的赋能平台，能力涵盖PROTAC、分子胶、AUTAC、LYTAC、DUBTAC、RIBOTAC、PHICS、以及DAC等主要分子类型。根据去年投资者开放日公布的信息，自2021年起，该平台已为靶向蛋白降解领域中66%的活跃公司提供了赋能合作。 展望未来，靶向蛋白降解剂有着更为深远的意义。正如这一领域的权威，丹娜-法伯癌症研究所（Dana–Farber Cancer Institute）的Eric Fischer教授指出的那样，利用口服小分子去降解蛋白质，可以让科学家摆脱“可成药性”的束缚，真正思考哪些靶点能够最大程度地改变疾病进程。我们也期待看到更多蛋白降解药物能在临床上获得积极进展，造福广大患者。 ▲欲了解更多前沿技术在生物医药产业中的应用，请长按扫描上方二维码，即可访问“药明直播间”，观看相关话题的直播讨论与精彩回放 参考资料： [1] Arvinas and Pfizer Announce Positive Topline Results from Phase 3 VERITAC-2 Clinical Trial. Retrieved March 11, 2025, from https://www.globenewswire.com/news-release/2025/03/11/3040386/0/en/Arvinas-and-Pfizer-Announce-Positive-Topline-Results-from-Phase-3-VERITAC-2-Clinical-Trial.html [2] 2024 WuXi AppTec Investor Day. Research Enabling Platforms Enhance CRDMO Model. Retrieved March 11, 2025, from https://static.wuxiapptec.com/6f/20240926/2024%20WuXi%20AppTec%20Investor%20Day%20-%20Research%20Enabling%20Platforms.pdf [3] PROTAC protein degraders to drug the undruggable enter phase 3 trials. Retrieved March 11, 2025, from https://www-nature-com.libproxy1.nus.edu.sg/articles/d41591-024-00072-8 [4] Nurix Corporate Presentation. Retrieved March 11, 2025, from https://ir.nurixtx.com/static-files/ee8cb2f8-e482-486e-a861-ececbd15f703 免责声明：药明康德内容团队专注介绍全球生物医药健康研究进展。本文仅作信息交流之目的，文中观点不代表药明康德立场，亦不代表药明康德支持或反对文中观点。本文也不是治疗方案推荐。如需获得治疗方案指导，请前往正规医院就诊。 版权说明：本文来自药明康德内容团队，欢迎个人转发至朋友圈，谢绝媒体或机构未经授权以任何形式转载至其他平台。转载授权请在「药明康德」微信公众号回复“转载”，获取转载须知。 分享，点赞，在看，聚焦全球生物医药健康创新