LYT-200

PDF Version PDF 版本RNS Number : 4332B RNS编号：4332B PureTech Health PLC 纯技术健康公司22 April 2026 2026年4月22日 22 April 2026 2026年4月22日PureTech Health plc PureTech Health plcPureTech Reports Positive Topline Data from Phase 1b Trial of LYT-200 in Relapsed/Refractory (R/R) High-Risk (HR) Myelodysplastic Syndrome (MDS) and R/R Acute Myeloid Leukemia (AML) PureTech报告了LYT-200在复发/难治性（R/R）高危（HR）骨髓增生异常综合征（MDS）和R/R急性髓系白血病（AML）的1b期试验中取得积极的初步数据。Phase 1b dataset with LYT-200 demonstrates complete responses and favorable tolerability across both R/R HR-MDS and R/R AML LYT-200的1b期数据集显示，在R/R HR-MDS和R/R AML中均获得了完全缓解且耐受性良好 PureTech's 纯技术的Founded Entity, Gallop Oncology, to advance LYT-200 first in R/R HR-MDS, with continued development planned in R/R AML 成立实体公司Gallop Oncology，以推进LYT-200在R/R HR-MDS中的首次应用，并计划继续在R/R AML中进行开发。Company plans to engage with the 公司计划参与其中U.S. Food and Drug Administration 美国食品药品监督管理局to discuss the design of a subsequent trial in R/R HR-MDS that has the potential to support registration 讨论在R/R HR-MDS中设计一个有可能支持注册的后续试验。PureTech Health plc 纯技术健康公司(Nasdaq: PRTC, LSE: PRTC) (' （纳斯达克：PRTC，伦敦证券交易所：PRTC）（'PureTech 纯科技' or the 'Company'), a hub-and-spoke biotherapeutics company dedicated to giving life to science and transforming innovation into value, today announced positive 或“公司”），一家致力于赋予科学生命并将创新转化为价值的轮辐式生物治疗公司，今天宣布了积极的topline data from the completed Phase 1b clinical trial of LYT-200, a first-in-class, fully human anti-galectin-9 monoclonal antibody, in heavily pretreated patients with relapsed/refractory (R/R) high-risk (HR) myelodysplastic syndrome (MDS) and R/R acute myeloid leukemia (AML). Based on the results, . LYT-200（一种首创的全人源抗半乳糖凝集素-9单克隆抗体）在经过多线治疗的复发/难治性（R/R）高危（HR）骨髓增生异常综合征（MDS）和R/R急性髓系白血病（AML）患者中已完成的1b期临床试验的顶线数据。基于这些结果， 。PureTech's 纯技术的Founded Entity, 成立实体，Gallop Oncology, has selected a recommended Phase 2 dose (RP2D) and intends to engage with the Gallop Oncology 已选定推荐的 Phase 2 剂量 (RP2D)，并计划进行交流。U.S. Food and Drug Administration 美国食品药品监督管理局(FDA) to discuss the design of a subsequent trial that could potentially support registration of LYT-200 in R/R HR-MDS. 与FDA讨论可能支持LYT-200在R/R HR-MDS中注册的后续试验设计。'The data from the completed Phase 1b trial highlight the potential for LYT-200 to offer a differentiated treatment approach across a range of myeloid hematological malignancies,' said “1b期试验完成的数据突显了LYT-200在多种髓系血液恶性肿瘤中提供差异化治疗方案的潜力，”表示Aleksandra Filipovic 亚历山德拉·菲利波维奇, M.D., Ph.D., Head of Oncology at 医学博士，肿瘤科主任PureTech 纯技术and Chief Medical Officer of Gallop Oncology. 'Across patients with R/R HR-MDS and R/R AML, treatment with LYT-200 resulted in Gallop Oncology的首席医疗官。“在R/R HR-MDS和R/R AML患者中，使用LYT-200进行治疗导致了deep responses 深度响应with an exceptionally favorable safety profile. Importantly, the data in R/R HR-MDS were particularly compelling and support prioritizing this indication, especially given the significant unmet need and lack of successful innovation to help these patients. W 具有非常有利的安全性特征。重要的是，R/R HR-MDS的数据尤其令人信服，并支持优先考虑这一适应症，特别是鉴于显著的未满足需求和缺乏帮助这些患者的成功创新。e intend to engage with the FDA to discuss the design of a subsequent trial 我们打算与FDA接洽，讨论后续试验的设计。in R/R HR- 在R/R HR-中MDS, as our goal is to accelerate delivery of this promising first-in-class therapy to patients while also laying the foundation for broader clinical development, including in AML.' MDS，我们的目标是加快这种有前景的首创疗法向患者的交付，同时也为更广泛的临床开发奠定基础，包括在AML中的应用。The completed Phase 1b trial (NCT05829226), conducted across nine 已完成的 1b 期试验（NCT05829226），在九个地方进行U.S. 美国sites, evaluated LYT-200 both as a monotherapy and in combination regimens in two heavily pretreated patient populations. 在两个经过多次治疗的患者群体中，评估了LYT-200作为单一疗法和联合治疗方案的效果。The study included dose escalation of monotherapy LYT-200, followed by dose escalation of LYT-200 in combination with a hypomethylating agent (HMA; azacitidine or decitabine) in patients with R/R HR-MDS and with venetoclax (VEN) and an HMA in R/R AML. 该研究包括对单药LYT-200的剂量递增，随后在R/R HR-MDS患者中与低甲基化剂（HMA；阿扎胞苷或地西他滨）联合使用LYT-200的剂量递增，以及在R/R AML患者中与维奈托克（VEN）和HMA联合使用的剂量递增。'The safety profile, combinatorial potential, and level of clinical activity observed with LYT-200 in this Phase 1b study across both R/R HR-MDS and R/R AML is very encouraging, particularly given the number of prior lines of treatment and the risk profile in the populations studied,' “在这一 1b 期研究中，LYT-200 在 R/R HR-MDS 和 R/R AML 中展现的安全性、组合潜力和临床活性水平非常令人鼓舞，特别是考虑到先前治疗的次数以及所研究人群的风险特征。”said 说Amir T. Fathi 阿米尔·T·法蒂, M.D., Program Director of the 医学博士，项目主任Center for Leukemia 白血病中心at the 在Mass General Brigham Cancer Institute 马萨诸塞综合医院布里格姆癌症研究所and Professor of Medicine at 医学教授Harvard Medical School 哈佛医学院. 。'In R/R high-risk MDS, where treatment options are extremely limited and outcomes are poor, the findings are particularly notable. In this context, the potential to achieve clinical responses without added toxicity would represent a meaningful advance in the MDS treatment landscape and warrants continued clinical development.'. “在治疗选择非常有限且预后较差的复发/难治性高危MDS中，这些发现尤其显著。在此背景下，能够在不增加毒性的情况下实现临床反应，将代表MDS治疗领域的一项有意义的进步，并值得进一步的临床开发。”'The results from this Phase 1b trial provide a strong foundation for the next stage of development of LYT-200,' said “这项1b期试验的结果为LYT-200的下一阶段开发提供了坚实的基础，”Eric Elenko 埃里克·埃伦科, Ph.D., President and Co-founder of 博士，总裁兼联合创始人PureTech 纯技术and Acting Chief Executive Officer of Gallop Oncology. 'Our decision to prioritize relapsed/refractory high-risk MDS reflects a focused and disciplined approach, grounded in both the data generated to date and the potential to address a tremendous patient need. We intend to engage with the FDA to discuss a subsequent trial design with the potential to support registration, while continuing to evaluate the broader potential of LYT-200.'. Gallop Oncology的代理首席执行官表示：“我们决定优先考虑复发/难治性高危MDS，这反映了一种专注且有条理的方法，基于迄今为止生成的数据和满足巨大患者需求的潜力。我们打算与FDA沟通，讨论一个有可能支持注册的后续试验设计，同时继续评估LYT-200的更广泛潜力。”TOPLINE SAFETY DATA 顶线安全数据LYT-200 demonstrated a favorable and consistent safety profile across all cohorts and dose levels studied (N=101), with no dose-limiting toxicities, infusion-related reactions, LYT-200 dose reductions, or LYT-200-related serious adverse events (AEs), discontinuations, or deaths. Importantly, no overlapping or additive toxicities were observed when LYT-200 was combined with an HMA or VEN/HMA.. LYT-200在所有研究队列和剂量水平（N=101）中表现出良好且一致的安全性，未出现剂量限制性毒性、输注相关反应、LYT-200剂量减少、LYT-200相关的严重不良事件（AEs）、停药或死亡。重要的是，当LYT-200与HMA或VEN/HMA联合使用时，未观察到重叠或叠加的毒性。Six patients at one study site reported experiencing hematology/chemistry-related Grade 3 or 4 AEs attributed as possibly related or related to LYT-200 in the combination arm at the RP2D dose. The reported AEs consisted of decreased levels of platelets, white blood cells, and neutrophils that were below the lower limit of normal physiological levels. 在一项研究中，六个患者报告在RP2D剂量下，联合治疗组中出现了可能与LYT-200相关或相关的3级或4级血液学/化学相关的不良事件（AE）。报告的不良事件包括血小板、白细胞和中性粒细胞水平下降至低于正常生理水平的下限。The blood count deficits for some of the relevant patients were present at baseline prior to the administration of LYT-200 and are common occurrences in patients due to the underlying advanced MDS/AML, as well as in those receiving VEN/HMA treatment. No other sites reported Grade 3 or greater AEs related to LYT-200 treatment.. 一些相关患者在使用LYT-200之前就存在基线水平的血细胞计数不足，这在患有潜在晚期MDS/AML的患者中是常见现象，接受VEN/HMA治疗的患者中也是如此。其他研究地点均未报告与LYT-200治疗相关的3级或更高级别的不良事件。TOPLINE 头条EFFICACY DATA 疗效数据Treatment with LYT-200 in combination with an HMA in R/R HR-MDS patients and VEN/HMA in R/R AML patients demonstrated robust antileukemic activity, including complete responses, bridging to transplant, and durable clinical benefit. The data also provided important insights into the contribution of LYT-200 within combination regimens.. 在R/R HR-MDS患者中使用LYT-200联合HMA治疗，以及在R/R AML患者中使用VEN/HMA治疗，显示出强大的抗白血病活性，包括完全缓解、桥接至移植以及持久的临床获益。数据还提供了关于LYT-200在联合方案中的贡献的重要见解。R/R HR-MDS 复发/难治性高危骨髓增生异常综合征Across all efficacy-evaluable 在所有可评估疗效的[1] [1]patients (n=11), the recommended Phase 2 dose (LYT-200 12mg/kg in combination with an HMA) demonstrated: 患者（n=11），推荐的二期剂量（LYT-200 12mg/kg 与 HMA 联合使用）显示：· ·27.3% complete response rate 27.3%的完全缓解率· ·9.1% partial response rate 9.1%的部分缓解率· ·9.1% marrow complete response rate 9.1%的骨髓完全缓解率· ·45.5% overall response rate 45.5%的总体响应率· ·18% conversion to transplant rate 18% 的移植率转换Due to the number of patients alive at the time of study completion (>50%), the upper bound of overall survival could not be calculated; therefore, the median overall survival for this cohort of 6.4 months is not considered fully mature. 由于研究结束时存活的患者数量较多（超过50%），无法计算总生存期的上限；因此，该队列6.4个月的中位总生存期不被视为完全成熟。Efficacy-evaluable patients had a median of 3 prior lines of therapy (range: 1-5), and all (100%) had previously been treated with an HMA. Additionally, all patients had high-risk cytogenetics, which - coupled with prior exposure to treatment - suggests biologically aggressive, treatment-refractory disease with elevated risk of progression and poor clinical outcomes. 疗效可评估的患者既往治疗中位数为3线（范围：1-5），并且所有患者（100%）均曾接受过HMA治疗。此外，所有患者均具有高危细胞遗传学特征，这与既往治疗暴露相结合，表明其疾病在生物学上具有侵袭性、对治疗耐药，并伴有较高的进展风险和不良临床结局。Taken together, these attributes underscore the potential mutation-agnostic mechanism of LYT-200 and its potential for broad clinical use.. 综合来看，这些属性突显了LYT-200潜在的与突变无关的作用机制及其广泛的临床应用潜力。R/R AML 复发/难治性急性髓系白血病Across all efficacy 横跨所有功效-e -evaluable 有价值的1 1patients (n=26), LYT-200 12mg/kg in combination with VEN/HMA demonstrated: 患者（n=26），LYT-200 12mg/kg 与 VEN/HMA 联用显示：· ·30.8% composite complete response rate 30.8%的复合完全缓解率[2] [2]; responders included patients with mutations associated with VEN resistance ；应答者包括与VEN耐药性相关的突变患者· ·7.7% partial response rate 7.7%的部分缓解率· ·42.3% overall response rate 42.3%的总体响应率 · ·19.2% conversion to transplant rate 19.2% 的移植转换率Due to the number of patients alive at the time of study completion (50%), the upper bound of overall survival could not be calculated; therefore, the median overall survival for this cohort of 8.2 months is not considered fully mature. 由于研究结束时存活的患者数量（50%），无法计算总生存期的上限；因此，该队列的中位总生存期为8.2个月，不被视为完全成熟。Efficacy-evaluable patients had a median of 2 prior lines of therapy (range: 1-9), and 84.6% had previously been treated with VEN/HMA. 疗效可评估的患者之前接受过中位数为2线的治疗（范围：1-9），且84.6%的患者曾接受过VEN/HMA治疗。INITIAL PHARMACODYNAMIC FINDINGS 初始药效学发现The systemic effects of LYT-200 were evaluated through pharmacodynamic analyses of peripheral blood mononuclear cells, a population of immune cells in the bloodstream that provides insight into how a treatment affects both the immune system and leukemic blast cells. These analyses suggest that LYT-200 engages complementary and potentially synergistic pathways directed at cancer cell killing and anti-cancer immune responses when combined with VEN and HMA-based therapy, which may contribute to the clinical activity observed in patients with relapsed/refractory disease following HMA and VEN/HMA treatment, in MDS and AML, respectively.. 通过对外周血单核细胞（一种血液中的免疫细胞群）进行药效学分析，评估了LYT-200的系统性效应，这些细胞可提供治疗对免疫系统和白血病母细胞影响的见解。这些分析表明，当LYT-200与VEN和基于HMA的疗法联合使用时，能够激活互补且潜在协同作用的通路，从而实现癌细胞杀伤和抗癌免疫反应，这可能有助于在MDS和AML中分别观察到的、经过HMA以及VEN/HMA治疗后复发/难治性疾病患者的临床活性。About Myelodysplastic Syndromes 关于骨髓增生异常综合征Myelodysplastic syndromes (MDS) are a group of serious blood cancers characterized by ineffective blood cell production in the bone marrow, leading to anemia, infections, and bleeding complications. 骨髓增生异常综合征 (MDS) 是一组严重的血液癌症，其特征是骨髓中血细胞生成无效，导致贫血、感染和出血并发症。[3] [3], ，[4] [4]MDS affects approximately 60,000-170,000 people in MDS影响了大约60,000-170,000人the United States 美国, with an estimated 30-40% of patients diagnosed with the more aggressive form of the disease known as high-risk (HR) MDS. ，约有30%-40%的患者被诊断为更具侵袭性的高风险（HR）MDS疾病形式。3, 3,[5] [5]HR-MDS is associated with poor outcomes, with median survival typically less than two years following diagnosis, and approximately 30% of patients progressing to acute myeloid leukemia (AML). 高危骨髓增生异常综合征（HR-MDS）预后较差，诊断后的中位生存期通常不到两年，且约30%的患者会进展为急性髓系白血病（AML）。4 4- -[6] [6]The current standard frontline treatment for HR-MDS are hypomethylating agents (HMAs), such as azacitidine and decitabine; however, most patients do not respond to these therapies or eventually stop benefiting from them. 高风险骨髓增生异常综合征 (HR-MDS) 的当前标准一线治疗方法是使用低甲基化药物 (HMAs)，例如阿扎胞苷和地西他滨；然而，大多数患者对这些疗法没有反应或最终停止从中受益。[7] [7]Once the disease becomes relapsed or refractory (R/R), outcomes are especially poor, with survival often limited to only a few months. 一旦疾病变得复发或难治性（R/R），结果尤其糟糕，生存期往往仅限于几个月。7 7, ，[8] [8]Treatment options for patients with R/R HR-MDS remain very limited. Only one therapy has been approved specifically for this setting in the past two decades, and it targets only a small subset of patients (~3-5%) with a specific genetic mutation. 复发/难治性高危骨髓增生异常综合征（R/R HR-MDS）患者的治疗选择仍然非常有限。在过去的二十年中，仅有一种疗法被专门批准用于此情况，且其仅针对一小部分（约3-5%）具有特定基因突变的患者。7 7As a result, there remains a significant need for new treatment approaches for patients with HR-MDS. 因此，对于高风险MDS患者，仍然存在对新治疗方法的重大需求。About Acute Myeloid Leukemia 关于急性髓系白血病Acute myeloid leukemia (AML) is an aggressive blood cancer characterized by the rapid growth of abnormal myeloid blast cells in the bone marrow and blood. It is the most common form of acute leukemia in adults, with a five-year survival rate of less than 30%. 急性髓系白血病（AML）是一种侵袭性的血液癌症，其特征是骨髓和血液中异常的髓系母细胞迅速增长。它是成人中最常见的急性白血病类型，五年生存率低于30%。[9] [9]Despite available therapies, many patients relapse or fail to respond, and outcomes are especially poor in the relapsed/refractory setting. Around 450,000 people globally are living with AML. 尽管有可用的治疗方法，许多患者仍会复发或未能响应，尤其是在复发/难治性情况下，结果尤其不佳。全球约有45万人患有急性髓系白血病（AML）。9 9AML is an area of urgent medical need where new therapies with improved safety, efficacy, and durability or responses are critical. Importantly, the incidence of AML is increasing, and the market is expected to grow to AML是一个迫切需要医疗的领域，新的疗法在安全性、有效性和持久性或反应方面都有显著改善。重要的是，AML的发病率正在增加，预计市场将会增长。$6 billion 60亿美元annually by 2030, 到2030年，每年[10] [10]underscoring the scale of the opportunity to bring forward therapies that are not only more effective but also applicable across a broader segment of patients. 强调了推出不仅更有效而且适用于更广泛患者群体的疗法的机会规模。 About LYT-200 关于LYT-200LYT-200 is a fully human IgG4 monoclonal antibody in development for the treatment of hematological malignancies. LYT-200 targets galectin-9, which is an important oncogenic driver and potent immunosuppressor in cancer, positioning it as a novel target for cancer therapy. LYT-200是一种处于开发阶段的全人源IgG4单克隆抗体，用于治疗血液系统恶性肿瘤。LYT-200靶向半乳糖凝集素-9（galectin-9），这是一种重要的致癌驱动因子和强大的免疫抑制剂，在癌症中具有关键作用，因此成为癌症治疗的一个新靶点。[11] [11]LYT-200 has been granted LYT-200 已被授予Fast Track 快速通道and 和Orphan Drug 孤儿药designations from the 来自的名称U.S. Food and Drug Administration 美国食品药品监督管理局(FDA) for the treatment of acute myeloid leukemia. 美国食品药品监督管理局（FDA）批准用于治疗急性髓系白血病。About Gallop Oncology 关于Gallop肿瘤学Gallop Oncology was founded by and is currently wholly-owned by Gallop Oncology 由其创立并且目前全资拥有。PureTech Health 纯技术健康plc (Nasdaq: PRTC, LSE: PRTC). Gallop is a clinical-stage biopharmaceutical company committed to transforming treatment paradigms for hematologic malignancies. Guided by science and driven to deliver meaningful outcomes for patients, Gallop is advancing a novel approach where efficacy, safety, and durability converge. plc（纳斯达克：PRTC，伦敦证券交易所：PRTC）。Gallop是一家处于临床阶段的生物制药公司，致力于改变血液恶性肿瘤的治疗模式。在科学的指导下，并以实现对患者有意义的结果为动力，Gallop正在推进一种新的方法，这种方法在疗效、安全性和持久性上达到了融合。Its lead candidate, LYT-200, is the most advanced candidate targeting galectin-9, an important oncogenic driver and potent immunosuppressor in cancer, offering a differentiated strategy to address some of the most challenging cancers. For more information, please visit . 其主要候选药物LYT-200是针对galectin-9的最先进的候选药物，galectin-9是癌症中重要的致癌驱动因子和强效免疫抑制剂，提供了一种差异化策略来应对一些最具挑战性的癌症。欲了解更多信息，请访问。www.galloponcology.com www.galloponcology.com. 。About PureTech Health 关于PureTech HealthPureTech Health 纯技术健康is a hub-and-spoke biotherapeutics company dedicated to giving life to science and transforming innovation into value. We do this through a proven, capital-efficient R&D model focused on opportunities with validated pharmacology and untapped potential to address significant patient needs. This strategy has produced dozens of therapeutic candidates, including three that have received . 是一家以枢纽和辐条模式运营的生物治疗公司，致力于赋予科学生命，并将创新转化为价值。我们通过一种经过验证的、资本高效的研发模式来实现这一目标，专注于那些具有已验证药理学和未开发潜力的机会，以满足重大的患者需求。这一战略已经产生了数十种治疗候选药物，其中三种已获得批准。U.S. 美国FDA approval. By identifying, shaping, and de-risking these high-conviction assets, and scaling them through dedicated structures backed by external capital, we accelerate their path to patients while creating sustainable value for shareholders. FDA批准。通过识别、塑造和降低这些高信念资产的风险，并通过外部资本支持的专用结构进行扩展，我们加速了它们对患者的路径，同时为股东创造了可持续的价值。For more information, visit 欲了解更多信息，请访问www.puretechhealth.com www.puretechhealth.comor connect with us on X (formerly Twitter) @puretechh. 或通过X（前身为Twitter）@puretechh与我们联系。Cautionary Note Regarding Forward-Looking Statements 关于前瞻性陈述的警告性说明This press release contains statements that are or may be forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. All statements contained in this press release that do not relate to matters of historical fact should be considered forward-looking statements, including without limitation those related to the LYT-200 development program and development plans, its potential benefits to patients, plans for discussions with regulatory authorities, the further development of the program, future presentation of additional data from the program and our future prospects, developments and strategies. 本新闻稿包含根据1995年《私人证券诉讼改革法》定义的前瞻性陈述或可能为前瞻性陈述的所有内容。本新闻稿中所有与历史事实无关的声明均应被视为前瞻性陈述，包括但不限于与LYT-200开发计划及开发规划、其对患者的潜在益处、与监管机构的沟通计划、该计划的进一步开发、未来发布的更多数据以及我们的未来前景、发展和策略相关的声明。The forward-looking statements are based on current expectations and are subject to known and unknown risks, uncertainties and other important factors that could cause actual results, performance and achievements to differ materially from current expectations, including, but not limited to, those risks, uncertainties and other important factors described under the caption 'Risk Factors' in our Annual Report on Form 20-F for the year ended December 31, 2024, filed with the . 前瞻性声明基于当前预期，但受已知和未知风险、不确定性以及其他可能导致实际结果、表现或成就与当前预期存在重大差异的重要因素的影响，包括但不限于我们截至2024年12月31日的年度Form 20-F报告中“风险因素”标题下描述的风险、不确定性及其他重要因素，该报告已提交给。SEC 证券交易委员会and in our other regulatory filings. These forward-looking statements are based on assumptions regarding the present and future business strategies of the Company and the environment in which it will operate in the future. Each forward-looking statement speaks only as at the date of this press release. 并包含在我们的其他监管文件中。这些前瞻性陈述是基于公司当前和未来业务战略的假设以及公司未来运营环境的假设。每个前瞻性陈述仅代表本新闻稿发布之日的情况。Except as required by law and regulatory requirements, we disclaim any obligation to update or revise these forward-looking statements, whether as a result of new information, future events or otherwise.. 除非法律和监管要求另有规定，我们不承担更新或修改这些前瞻性陈述的义务，无论是由于新信息、未来事件或其他原因。PureTech 纯科技Public Relations 公共关系publicrelations@puretechhealth.com 公共关系@纯科技健康.comInvestor Relations 投资者关系IR@puretechhealth.com IR@puretechhealth.comUK 英国/EU Media 欧盟媒体Ben Atwell 本·阿特韦尔, ，Rob Winder 罗布·温德+44 (0) 20 3727 1000 +44 (0) 20 3727 1000puretech@fticonsulting.com 纯技术@fticonsulting.comUS Media 美国媒体Justin Chen 陈贾斯汀jchen@tenbridgecommunications.com jchen@tenbridgecommunications.com[1] [1]Efficacy evaluable is defined in the protocol as all patients who received a minimum one full cycle of LYT-200 (four doses) and had a minimum of one post-baseline disease assessment. The intent-to-treat population for the R/R HR-MDS cohort was n=12 and for the R/R AML cohort was n=33. 方案中将可评估疗效定义为所有接受至少一个完整周期LYT-200（四剂）治疗并且有至少一次基线后疾病评估的患者。R/R HR-MDS队列的意向治疗人群为n=12，R/R AML队列为n=33。[2] [2]Complete response + 完全响应 +complete response with incomplete hematological recovery 完全缓解伴不完全血液学恢复[3] [3]American Cancer Society 美国癌症协会. (2023). 。 （2023）。What Is Myelodysplastic Syndrome? 什么是骨髓增生异常综合征？Retrieved from 检索自https://www.cancer.org https://www.cancer.org[4] [4]National Comprehensive Cancer Network. (2024). 国家综合癌症网络。（2024）NCCN Clinical Practice Guidelines in Oncology: Myelodysplastic Syndromes (Version 2.2024). NCCN临床实践指南：肿瘤学：骨髓增生异常综合征（2024年第2版）。Retrieved from 检索自https://www.nccn.org https://www.nccn.org[5] [5]Greenberg, P. L., Tuechler, H., Schanz, J., Sanz, G., Garcia-Manero, G., Solé, F., Bennett, 格林伯格，P. L.，图赫勒，H.，尚茨，J.，桑兹，G.，加西亚-马内罗，G.，索莱，F.，贝内特，J. M J. M., Bowen, D., Fenaux, P., Dreyfus, F., Kantarjian, H., Kuendgen, A., Levis, A., Malcovati, L., Cazzola, M., & Haase, D. (2012). Revised International Prognostic Scoring System for myelodysplastic syndromes. ., Bowen, D., Fenaux, P., Dreyfus, F., Kantarjian, H., Kuendgen, A., Levis, A., Malcovati, L., Cazzola, M., & Haase, D. (2012). 骨髓增生异常综合征的修订国际预后评分系统。Blood, 120 血液，120(12), 2454-2465. (12), 2454-2465。https://doi.org/10.1182/blood-2012-03-420489 https://doi.org/10.1182/blood-2012-03-420489[6] [6]Ma, X. (2012). Epidemiology of myelodysplastic syndromes. 马，X.（2012）。骨髓增生异常综合征的流行病学。The American Journal of Medicine 美国医学杂志, 125 ，125(7 Suppl), S2-S5. (7增刊), S2-S5。https://doi.org/10.1016/j.amjmed.2012.04.014 https://doi.org/10.1016/j.amjmed.2012.04.014[7] [7]Garcia-Manero, G., Fenaux, P., Al-Kali, A., Baer, 加西亚-马内罗，G.，费纳克斯，P.，阿尔-卡利，A.，贝尔， M. R M. R., Sekeres, M. A., Roboz, ., Sekeres, M. A., Roboz,G. J G. J., et al. (2016). Rigosertib versus best supportive care for patients with high-risk myelodysplastic syndromes after failure of hypomethylating drugs (ONTIME): A randomised, controlled, phase 3 trial. ., 等 (2016). Rigosertib 对比最佳支持治疗用于高危骨髓增生异常综合征患者在低甲基化药物失败后的疗效（ONTIME）：一项随机、对照、3期试验。Lancet Oncology, 17 柳叶刀肿瘤学，17 (4), 496-508. (4), 496-508。https://doi.org/10.1016/S1470-2045(16)00009-7 https://doi.org/10.1016/S1470-2045(16)00009-7[8] [8]Prébet, T., 普雷贝，T.，Gore, S 戈尔，S. D., Esterni, B., Gardin, C., Itzykson, R., Thepot, S., Quesnel, B., Dreyfus, F., Beyne-Rauzy, O., Vey, N., Recher, C., Adès, L., Fenaux, P., & Groupe Francophone des Myélodysplasies. (2011). Outcome of patients with higher-risk myelodysplastic syndromes after azacitidine treatment failure. D., Esterni, B., Gardin, C., Itzykson, R., Thepot, S., Quesnel, B., Dreyfus, F., Beyne-Rauzy, O., Vey, N., Recher, C., Adès, L., Fenaux, P., & 法语骨髓增生异常综合症小组（Groupe Francophone des Myélodysplasies）。(2011)。阿扎胞苷治疗失败后高危骨髓增生异常综合症患者的预后。Journal of Clinical Oncology 临床肿瘤学杂志, 29 ，29(24), 3322-3327. (24), 3322-3327。https://doi.org/10.1200/JCO.2011.35.8135 https://doi.org/10.1200/JCO.2011.35.8135[9] [9]Acute Myeloid Leukemia - Cancer Stat Facts. (n.d.). 急性髓系白血病 - 癌症统计资料。 （无日期）。National Cancer Institute 国家癌症研究所[10] [10]Grand View Research 大视野研究 , Acute Myeloid Leukemia Treatment Market Size, Share & Trends Analysis Report By Disease, By Treatment (Chemotherapy, Targeted Therapy, Immunotherapy), By Route of Administration, By End Use, By Region, And Segment Forecasts, 2025-2030 急性髓系白血病治疗市场规模、份额与趋势分析报告：按疾病、治疗方法（化疗、靶向治疗、免疫治疗）、给药途径、最终用途、地区划分，以及细分市场预测，2025-2030年。[11] [11]Karkempetzaki, A. I., Schatton, T., & Barthel, S. R. (2025). Galectin-9-An emerging Glyco-Immune checkpoint target for cancer therapy. Karkempetzaki, A. I., Schatton, T., & Barthel, S. R. (2025). 半乳糖凝集素-9——一种新兴的癌症治疗糖免疫检查点靶标。International Journal of Molecular Sciences 国际分子科学杂志, ，26 26(16), 7998. (16), 7998。https://doi.org/10.3390/ijms26167998 https://doi.org/10.3390/ijms26167998This information is provided by Reach, the non-regulatory press release distribution service of RNS, part of the 这部分信息由RNS的非监管新闻稿分发服务Reach提供，London Stock Exchange 伦敦证券交易所. Terms and conditions relating to the use and distribution of this information may apply. For further information, please contact 与此信息的使用和分发相关的条款和条件可能适用。欲了解更多信息，请联系rns@lseg.com rns@lseg.comor visit 或访问www.rns.com www.rns.com. 。RNS may use your IP address to confirm compliance with the terms and conditions, to analyse how you engage with the information contained in this communication, and to share such analysis on an anonymised basis with others as part of our commercial services. For further information about how RNS and the . RNS可能会使用您的IP地址来确认您是否遵守了条款和条件，分析您如何与本通讯中包含的信息互动，并在我们的商业服务范围内以匿名方式与他人分享此类分析。有关RNS及更多信息，请参阅。London Stock Exchange 伦敦证券交易所use the personal data you provide us, please see our 使用您提供给我们的个人数据，请参阅我们的Privacy Policy 隐私政策. 。END 结束NRAEAALAAEPKEEA NRAEAALAAEPKEEA

Phase 1b dataset with LYT-200 demonstrates complete responses and favorable tolerability across both R/R HR-MDS and R/R AML PureTech’s Founded Entity, Gallop Oncology, to advance LYT-200 first in R/R HR-MDS, with continued development planned in R/R AML Company plans to engage with the U.S. Food and Drug Administration to discuss the design of a subsequent trial in R/R HR-MDS that has the potential to support registration BOSTON--(BUSINESS WIRE)-- PureTech Health plc (Nasdaq: PRTC, LSE: PRTC) ("PureTech" or the "Company"), a hub-and-spoke biotherapeutics company dedicated to giving life to science and transforming innovation into value, today announced positive topline data from the completed Phase 1b clinical trial of LYT-200, a first-in-class, fully human anti-galectin-9 monoclonal antibody, in heavily pretreated patients with relapsed/refractory (R/R) high-risk (HR) myelodysplastic syndrome (MDS) and R/R acute myeloid leukemia (AML). Based on the results, PureTech’s Founded Entity, Gallop Oncology, has selected a recommended Phase 2 dose (RP2D) and intends to engage with the U.S. Food and Drug Administration (FDA) to discuss the design of a subsequent trial that could potentially support registration of LYT-200 in R/R HR-MDS. “The data from the completed Phase 1b trial highlight the potential for LYT-200 to offer a differentiated treatment approach across a range of myeloid hematological malignancies,” said Aleksandra Filipovic, M.D., Ph.D., Head of Oncology at PureTech and Chief Medical Officer of Gallop Oncology. “Across patients with R/R HR-MDS and R/R AML, treatment with LYT-200 resulted in deep responses with an exceptionally favorable safety profile. Importantly, the data in R/R HR-MDS were particularly compelling and support prioritizing this indication, especially given the significant unmet need and lack of successful innovation to help these patients. We intend to engage with the FDA to discuss the design of a subsequent trial in R/R HR-MDS, as our goal is to accelerate delivery of this promising first-in-class therapy to patients while also laying the foundation for broader clinical development, including in AML.” The completed Phase 1b trial (NCT05829226), conducted across nine U.S. sites, evaluated LYT-200 both as a monotherapy and in combination regimens in two heavily pretreated patient populations. The study included dose escalation of monotherapy LYT-200, followed by dose escalation of LYT-200 in combination with a hypomethylating agent (HMA; azacitidine or decitabine) in patients with R/R HR-MDS and with venetoclax (VEN) and an HMA in R/R AML. “The safety profile, combinatorial potential, and level of clinical activity observed with LYT-200 in this Phase 1b study across both R/R HR-MDS and R/R AML is very encouraging, particularly given the number of prior lines of treatment and the risk pro the populations studied,” said Amir T. Fathi, M.D., Program Director of the Center for Leukemia at the Mass General Brigham Cancer Institute and Professor of Medicine at Harvard Medical School. “In R/R high-risk MDS, where treatment options are extremely limited and outcomes are poor, the findings are particularly notable. In this context, the potential to achieve clinical responses without added toxicity would represent a meaningful advance in the MDS treatment landscape and warrants continued clinical development.” “The results from this Phase 1b trial provide a strong foundation for the next stage of development of LYT-200,” said Eric Elenko, Ph.D., President and Co-founder of PureTech and Acting Chief Executive Officer of Gallop Oncology. “Our decision to prioritize relapsed/refractory high-risk MDS reflects a focused and disciplined approach, grounded in both the data generated to date and the potential to address a tremendous patient need. We intend to engage with the FDA to discuss a subsequent trial design with the potential to support registration, while continuing to evaluate the broader potential of LYT-200.” TOPLINE SAFETY DATA LYT-200 demonstrated a favorable and consistent safety pro all cohorts and dose levels studied (N=101), with no dose-limiting toxicities, infusion-related reactions, LYT-200 dose reductions, or LYT-200-related serious adverse events (AEs), discontinuations, or deaths. Importantly, no overlapping or additive toxicities were observed when LYT-200 was combined with an HMA or VEN/HMA. Six patients at one study site reported experiencing hematology/chemistry-related Grade 3 or 4 AEs attributed as possibly related or related to LYT-200 in the combination arm at the RP2D dose. The reported AEs consisted of decreased levels of platelets, white blood cells, and neutrophils that were below the lower limit of normal physiological levels. The blood count deficits for some of the relevant patients were present at baseline prior to the administration of LYT-200 and are common occurrences in patients due to the underlying advanced MDS/AML, as well as in those receiving VEN/HMA treatment. No other sites reported Grade 3 or greater AEs related to LYT-200 treatment. TOPLINE EFFICACY DATA Treatment with LYT-200 in combination with an HMA in R/R HR-MDS patients and VEN/HMA in R/R AML patients demonstrated robust antileukemic activity, including complete responses, bridging to transplant, and durable clinical benefit. The data also provided important insights into the contribution of LYT-200 within combination regimens. R/R HR-MDS Across all efficacy-evaluable 1 patients (n=11), the recommended Phase 2 dose (LYT-200 12mg/kg in combination with an HMA) demonstrated: 27.3% complete response rate 9.1% partial response rate 9.1% marrow complete response rate 45.5% overall response rate 18% conversion to transplant rate Due to the number of patients alive at the time of study completion (>50%), the upper bound of overall survival could not be calculated; therefore, the median overall survival for this cohort of 6.4 months is not considered fully mature. Efficacy-evaluable patients had a median of 3 prior lines of therapy (range: 1-5), and all (100%) had previously been treated with an HMA. Additionally, all patients had high-risk cytogenetics, which – coupled with prior exposure to treatment – suggests biologically aggressive, treatment-refractory disease with elevated risk of progression and poor clinical outcomes. Taken together, these attributes underscore the potential mutation-agnostic mechanism of LYT-200 and its potential for broad clinical use. R/R AML Across all efficacy-evaluable 1 patients (n=26), LYT-200 12mg/kg in combination with VEN/HMA demonstrated: 30.8% composite complete response rate 2 ; responders included patients with mutations associated with VEN resistance 7.7% partial response rate 42.3% overall response rate 19.2% conversion to transplant rate Due to the number of patients alive at the time of study completion (50%), the upper bound of overall survival could not be calculated; therefore, the median overall survival for this cohort of 8.2 months is not considered fully mature. Efficacy-evaluable patients had a median of 2 prior lines of therapy (range: 1-9), and 84.6% had previously been treated with VEN/HMA. INITIAL PHARMACODYNAMIC FINDINGS The systemic effects of LYT-200 were evaluated through pharmacodynamic analyses of peripheral blood mononuclear cells, a population of immune cells in the bloodstream that provides insight into how a treatment affects both the immune system and leukemic blast cells. These analyses suggest that LYT-200 engages complementary and potentially synergistic pathways directed at cancer cell killing and anti-cancer immune responses when combined with VEN and HMA-based therapy, which may contribute to the clinical activity observed in patients with relapsed/refractory disease following HMA and VEN/HMA treatment, in MDS and AML, respectively. About Myelodysplastic Syndromes Myelodysplastic syndromes (MDS) are a group of serious blood cancers characterized by ineffective blood cell production in the bone marrow, leading to anemia, infections, and bleeding complications. 3, 4 MDS affects approximately 60,000–170,000 people in the United States, with an estimated 30–40% of patients diagnosed with the more aggressive form of the disease known as high-risk (HR) MDS. 3, 5 HR-MDS is associated with poor outcomes, with median survival typically less than two years following diagnosis, and approximately 30% of patients progressing to acute myeloid leukemia (AML). 4-6 The current standard frontline treatment for HR-MDS are hypomethylating agents (HMAs), such as azacitidine and decitabine; however, most patients do not respond to these therapies or eventually stop benefiting from them. 7 Once the disease becomes relapsed or refractory (R/R), outcomes are especially poor, with survival often limited to only a few months. 7,8 Treatment options for patients with R/R HR-MDS remain very limited. Only one therapy has been approved specifically for this setting in the past two decades, and it targets only a small subset of patients (~3–5%) with a specific genetic mutation. 7 As a result, there remains a significant need for new treatment approaches for patients with HR-MDS. About Acute Myeloid Leukemia Acute myeloid leukemia (AML) is an aggressive blood cancer characterized by the rapid growth of abnormal myeloid blast cells in the bone marrow and blood. It is the most common form of acute leukemia in adults, with a five-year survival rate of less than 30%. 9 Despite available therapies, many patients relapse or fail to respond, and outcomes are especially poor in the relapsed/refractory setting. Around 450,000 people globally are living with AML. 9 AML is an area of urgent medical need where new therapies with improved safety, efficacy, and durability or responses are critical. Importantly, the incidence of AML is increasing, and the market is expected to grow to $6 billion annually by 2030, 10 underscoring the scale of the opportunity to bring forward therapies that are not only more effective but also applicable across a broader segment of patients. About LYT-200 LYT-200 is a fully human IgG4 monoclonal antibody in development for the treatment of hematological malignancies. LYT-200 targets galectin-9, which is an important oncogenic driver and potent immunosuppressor in cancer, positioning it as a novel target for cancer therapy. 11 LYT-200 has been granted Fast Track and Orphan Drug designations from the U.S. Food and Drug Administration (FDA) for the treatment of acute myeloid leukemia. About Gallop Oncology Gallop Oncology was founded by and is currently wholly-owned by PureTech Health plc (Nasdaq: PRTC, LSE: PRTC). Gallop is a clinical-stage biopharmaceutical company committed to transforming treatment paradigms for hematologic malignancies. Guided by science and driven to deliver meaningful outcomes for patients, Gallop is advancing a novel approach where efficacy, safety, and durability converge. Its lead candidate, LYT-200, is the most advanced candidate targeting galectin-9, an important oncogenic driver and potent immunosuppressor in cancer, offering a differentiated strategy to address some of the most challenging cancers. For more information, please visit . About PureTech Health PureTech Health is a hub-and-spoke biotherapeutics company dedicated to giving life to science and transforming innovation into value. We do this through a proven, capital-efficient R&D model focused on opportunities with validated pharmacology and untapped potential to address significant patient needs. This strategy has produced dozens of therapeutic candidates, including three that have received U.S. FDA approval. By identifying, shaping, and de-risking these high-conviction assets, and scaling them through dedicated structures backed by external capital, we accelerate their path to patients while creating sustainable value for shareholders. For more information, visit or connect with us on X (formerly Twitter) @puretechh. Cautionary Note Regarding Forward-Looking Statements This press release contains statements that are or may be forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. All statements contained in this press release that do not relate to matters of historical fact should be considered forward-looking statements, including without limitation those related to the LYT-200 development program and development plans, its potential benefits to patients, plans for discussions with regulatory authorities, the further development of the program, future presentation of additional data from the program and our future prospects, developments and strategies. The forward-looking statements are based on current expectations and are subject to known and unknown risks, uncertainties and other important factors that could cause actual results, performance and achievements to differ materially from current expectations, including, but not limited to, those risks, uncertainties and other important factors described under the caption "Risk Factors" in our Annual Report on Form 20-F for the year ended December 31, 2024, filed with the SEC and in our other regulatory filings. These forward-looking statements are based on assumptions regarding the present and future business strategies of the Company and the environment in which it will operate in the future. Each forward-looking statement speaks only as at the date of this press release. Except as required by law and regulatory requirements, we disclaim any obligation to update or revise these forward-looking statements, whether as a result of new information, future events or otherwise. 1 Efficacy evaluable is defined in the protocol as all patients who received a minimum one full cycle of LYT-200 (four doses) and had a minimum of one post-baseline disease assessment. The intent-to-treat population for the R/R HR-MDS cohort was n=12 and for the R/R AML cohort was n=33. 2 Complete response + complete response with incomplete hematological recovery 3 American Cancer Society. (2023). What Is Myelodysplastic Syndrome? Retrieved from 4 National Comprehensive Cancer Network. (2024). NCCN Clinical Practice Guidelines in Oncology: Myelodysplastic Syndromes (Version 2.2024). Retrieved from 5 Greenberg, P. L., Tuechler, H., Schanz, J., Sanz, G., Garcia-Manero, G., Solé, F., Bennett, J. M., Bowen, D., Fenaux, P., Dreyfus, F., Kantarjian, H., Kuendgen, A., Levis, A., Malcovati, L., Cazzola, M., & Haase, D. (2012). Revised International Prognostic Scoring System for myelodysplastic syndromes. Blood, 120 (12), 2454–2465. 6 Ma, X. (2012). Epidemiology of myelodysplastic syndromes. The American Journal of Medicine, 125 (7 Suppl), S2–S5. 7 Garcia-Manero, G., Fenaux, P., Al-Kali, A., Baer, M. R., Sekeres, M. A., Roboz, G. J., et al. (2016). Rigosertib versus best supportive care for patients with high-risk myelodysplastic syndromes after failure of hypomethylating drugs (ONTIME): A randomised, controlled, phase 3 trial. Lancet Oncology, 17(4), 496–508. (16)00009-7 8 Prébet, T., Gore, S. D., Esterni, B., Gardin, C., Itzykson, R., Thepot, S., Quesnel, B., Dreyfus, F., Beyne-Rauzy, O., Vey, N., Recher, C., Adès, L., Fenaux, P., & Groupe Francophone des Myélodysplasies. (2011). Outcome of patients with higher-risk myelodysplastic syndromes after azacitidine treatment failure. Journal of Clinical Oncology, 29 (24), 3322–3327. 9 Acute Myeloid Leukemia - Cancer Stat Facts. (n.d.). National Cancer Institute 10 Grand View Research, Acute Myeloid Leukemia Treatment Market Size, Share & Trends Analysis Report By Disease, By Treatment (Chemotherapy, Targeted Therapy, Immunotherapy), By Route of Administration, By End Use, By Region, And Segment Forecasts, 2025-2030 11 Karkempetzaki, A. I., Schatton, T., & Barthel, S. R. (2025). Galectin-9—An emerging Glyco-Immune checkpoint target for cancer therapy. International Journal of Molecular Sciences , 26 (16), 7998. Contacts PureTech Public Relations publicrelations@puretechhealth.com Investor Relations IR@puretechhealth.com UK/EU Media Ben Atwell, Rob Winder +44 (0) 20 3727 1000 puretech@fticonsulting.com US Media Justin Chen jchen@tenbridgecommunications.com