2seventy Bio, Inc.

同写意年度巨献！！大会特设“跨境BD与新药出海”分会，7月25-26日，邀您相聚金鸡湖畔，与5000人一起为中国医药创新“同写意”！TONACEA012025年前四个月医药交易异常活跃2025年初，尽管全球宏观环境仍充满不确定性，生物科技行业整体面临融资紧缩、估值下探的压力，但大型跨国制药企业在外部交易市场上的活跃度却出人意料地高。根据统计，仅在1月至4月，全球大型制药公司共完成38笔资产交易，涵盖31笔授权合作和7笔并购，累计交易金额接近600亿美元，其中授权交易约330亿美元，并购交易约270亿美元（本文中交易金额包括潜在里程碑付款）（表1）。表1. 2025年前4个月大型制药公司授权与并购交易表TONACEA02中国资产成为主角2025年前四个月，共有8笔交易来自中国制药企业，占全部交易数量的21%，对应交易金额为64.3亿美元，占比为12%（图1-2）。这样的数据已经相当抢眼。更重要的是，中国药企正在从“区域合作提供方”向“全球管线共建方”转变，交易结构也更趋复杂、估值更具弹性。图1. 2025年前四月大型制药公司资产交易中国资产数量图图2. 2025年前四月大型制药公司资产交易中国资产金额图交易金额方面，8笔交易中已有多项披露出数亿美元乃至几十亿美元级别的潜在价值，总金额超过64亿美元，显示出全球药企对中国企业早期资产的重视正在加深。更重要的是，这些交易中大多数已脱离“区域市场权利转让”模式，转而成为围绕差异机制、创新模态和全球权益布局的合作。参与交易的中国公司包括恒瑞医药（2笔）、信达生物、先声药业、元思生肽、和正医药、上海和誉、苏州浦合医药（TUL），合作对象则包括罗氏、阿斯利康、默沙东、艾伯维、强生、拜耳等全球头部制药企业。这些交易的一个共同点是：大多不再局限于区域性市场权利的转让，而是围绕核心机制与全球权益展开的合作。其中，金额最大的几项交易包括阿斯利康以34.75亿美元从元思生肽引入多肽类资产，聚焦代谢与炎症免疫交叉通路；艾伯维以10.55亿美元从先声药业引入一款靶向GPRC5D、BCMA与CD3的三特异性抗体SIM0500；罗氏以10.8亿美元从信达生物引入靶向DLL3的1期ADC资产IBI3009。从阶段来看，这些交易资产大多处于临床前至1期阶段，但估值普遍不低，反映出国际药企对中国公司所提供的早期资产的认可正在逐步增强。在全球大型药企面临内部管线空缺、急需通过外部创新补强的背景下，中国药企正在成为其全球BD布局的重要组成部分。2025年的开局，或许可以看作是中国企业“在全球授权市场中具备持续输出能力”的起点。不是偶然崛起，而是结构性进入。TONACEA03肿瘤学资产交易依旧火热观察2025年前四个月的38笔来自大型制药公司的资产交易，按适应症划分呈现来看，肿瘤学依然是交易数量最多的适应症领域。但在交易金额方面，代谢类与炎症免疫类疾病显示出更强的估值上升趋势（图3-4）。值得注意的是，一些金额特别突出的交易，更多由企业与产品本身驱动，而非反映适应症热度。图3. 2025年前四月大型制药公司资产交易数量的适应症关联图图4. 2025年前四月大型制药公司资产交易金额的适应症关联图从2025年前四个月已披露的38笔大型制药公司授权与并购交易来看，肿瘤学依旧是交易最集中的适应症领域，累计13笔交易（占比34%），其中包括多项处于后期开发或已上市的资产，显示出肿瘤药物商业化潜力依然受到高度认可。例如，Merck以6000万美元引进PharmaMar的上市药物Zepzelca（DNA靶点小分子），用于二线小细胞肺癌的治疗；BMS以2.86亿美元完成对2seventy bio旗下CAR-T疗法Abecma的并购交易，进一步巩固其在BCMA靶点治疗中的领导地位。此外，艾伯维以10.55亿美元从先声药业引进三特异性抗体SIM0500，靶向GPRC5D、BCMA和CD3，体现出其在复杂免疫机制下探索多靶点T细胞重定向疗法的规划。炎症与免疫学领域则紧随其后，共计7笔交易，且靶点与技术形式多样，突显出该领域的机制复杂性与早期布局特征。例如，赛诺菲以18.45亿美元获得Earendil Labs旗下α4β7与TL1A靶点的双特异性抗体，聚焦于炎症性肠病（IBD）等自身免疫适应症；赛诺菲还以19亿美元引进Dren Bio开发中的CD20靶点双抗DR-0201，延续其在炎性疾病与肿瘤交叉领域的战略整合。诺华则通过Kyorin交易获得靶向MRGPRX2的小分子候选药，涉足皮肤疾病与免疫机制交叉研究。这些案例显示，尽管炎症与免疫类产品在交易金额上略逊于肿瘤资产，但其技术含量与平台型潜力获得持续押注。代谢类疾病的布局在今年表现出“重资本+早期锁定”的双重特征，共有5笔交易（13%），金额总计超过106亿美元（20%）。罗氏以52.5亿美元从Zealand Pharma引进GLP-1多肽Petrelintide（处于2b期），成为今年迄今为止单笔最大代谢类交易。同样，诺和诺德以20亿美元获得TUL的UBT251（GLP-1/GIP/Glucagon三受体共激动剂），进一步扩充其代谢领域的管线组合。此外，阿斯利康以34.75亿美元交易元思生肽，虽靶点未披露，但明确用于代谢/炎症方向，也体现出大公司对早期多肽平台的积极投资。相较之下，神经疾病领域虽仅1笔交易，但由强生以146亿美元收购Intra-Cellular Therapies及其产品Caplyta（上市药物），使其在交易金额占比中跃居第一。这种“以一敌十”的集中押注策略凸显了强生在精神疾病治疗市场的长远战略，也揭示出中枢神经系统药物在突破后期商业瓶颈后所能释放的巨大估值潜力。TONACEA04早期资产受到重视从交易资产的临床阶段分布来看，2025年前四个月的交易热度明显集中在早期资产阶段，尤其是一期项目，共计约14笔交易，总交易金额超过160亿美元，是当前产业最为密集的投资区间（图5）。图5. 2025年前四月大型制药公司资产交易数量与金额的阶段关联图图6. 2025年前四月大型制药公司资产交易平均金额的阶段关联图典型的交易包括诺和诺德以20亿美元引进TUL公司的三重受体激动剂UBT251，以及阿斯利康与元思生肽达成的34.75亿美元早期合作协议。企业愿意为这些尚处于安全性初步验证阶段的资产投入巨资，说明其对机制差异化、潜在同类最优产品的高度期待。临床前和药物发现阶段的交易数量也相对可观，分别为10笔和3笔，但其平均交易金额相对较低（图5-6）。临床前阶段如赛诺菲引进Earendil Labs的双特异性抗体组合（18.45亿美元），为早期交易中的高价值代表；而药物发现阶段虽金额偏低，但往往伴随平台型技术的引进，反映出大型药企在技术“早押注”上的战略一致性。在2期与3期项目方面，尽管数量有限，但价格可观。如罗氏以52.5亿美元获得Zealand Pharma的Petrelintide（2b期），表明部分项目在取得初步有效性信号后便能快速提升估值。最值得关注的是已上市资产，虽然在交易数量上不算最多，但其平均交易金额高达30亿元美元以上（图6），远高于其他阶段。比如强生以146亿美元收购Intra-Cellular Therapies的Caplyta（神经科已上市药物），这类交易不仅出于对即期营收的考量，也体现出大型药企“补短板、买管线”的并购策略依然活跃。大型制药公司早期押注用于拓展靶点与创新机制空间，后期并购用于加强产品组合与商业回报。这一趋势也在适应症分布中有所体现，代谢类疾病与神经疾病交易多集中于1期至上市阶段，而炎症与免疫领域更多聚焦于临床前与药物发现期。TONACEA05小分子资产依然受到关注从模态角度来看，2025年前四个月的大型制药公司资产交易中，小分子药物依然是交易量和交易金额双料第一。共有21笔交易涉及小分子，交易金额累计超过270亿美元（图7）。典型交易如强生以146亿美元收购的精神疾病药物Caplyta，以及礼来、艾伯维等引进的多项肿瘤与代谢类小分子项目。这种强势地位得益于小分子药物在开发周期、口服便利性、适应症多样化等方面的优势，尤其在肿瘤、炎症与代谢疾病等多个赛道中仍有可挖掘的差异化靶点。图7. 2025年前四月大型制药公司资产交易数量与金额的模态关联图图8. 2025年前四月大型制药公司资产交易平均金额的模态关联图多肽类药物在交易平均金额上表现最为亮眼（图8）。尽管交易数量仅为4笔，但平均每笔交易金额高达32亿美元，显著高于小分子（13亿）与抗体（16亿），反映出其在代谢类疾病（尤其是GLP-1及其拓展靶点）中的高商业价值。罗氏以52.5亿美元收购Zealand Pharma的多肽资产Petrelintide、诺和诺德以20亿美元引进TUL的3G受体共激动剂多肽资产UBT251、阿斯利康与元思生肽的34.75亿美元交易，均属这一趋势的代表。这些交易不仅体现出企业对减重与糖尿病治疗机制升级的需求，也显示出多肽药物从“小众到主流”的路径逐渐成熟。抗体类资产（含单抗、双特异性抗体与三特异性抗体）保持中等交易活跃度与中高估值，代表交易如赛诺菲以18.45亿美元交易Earendil Labs的双抗项目、艾伯维引进Xilio的多靶点抗体平台（21.52亿美元）等，主要集中于肿瘤与炎症类适应症。值得注意的是，这一领域正逐渐由传统单抗向更复杂结构进化，包括双/三特异抗体、ADC及细胞免疫结合体。而ADC（抗体偶联药物）与RNA疗法在数量与金额上均较为有限，平均金额亦处低位，真正进入大型交易的项目目前仍属少数，但不排除接下来出现此类的大交易。其中BI与Oxford Biotherapeutics、罗氏与信达生物的交易标志着ADC主要处于临床前或早期验证阶段，仍需时间验证其差异化临床价值。细胞和基因疗法（如CAR-T、反义核酸等）也呈现出“低频高值”的特征，BMS并购2seventy bio获取Abecma（CAR-T）、罗氏交易Oak Hill Bio引进反义寡核苷酸Rugonersen等，提示该类模态依旧是少数大项目的重点，但不具备广泛铺开趋势。总体来看，小分子仍是主力、多肽强势崛起、抗体结构不断复杂化，而新型模态如ADC、RNA与细胞治疗尚处于窗口观察期。从适应症联动来看，多肽主要集中于代谢类疾病，小分子分布最广，而抗体与ADC则扎堆肿瘤与免疫相关领域。参考文献：uerstein, A. M&A is back, but nothing in biotech is neat or simple. STAT. 01. 05. 2025.Armitage, P. Licensing partnerships in the life sciences: Emerging and expected trends in 2025. Lexology. 30. 04. 2025.2025 biotech deals tracker: the latest partnerships and M&A activities. Labiotech. Retrieved on 03. 05. 2025.Pannu, A. Big Pharma M&A and licensing deal trends in 2025. LinkedIn.

作者：布布尽管代谢疾病市场在肥胖治疗需求推动下迅速升温，传染病合作也曾因疫情短暂活跃，但在生物医药领域真正长期占据“C位”的，依旧是肿瘤领域。根据Biomedtracker最新发布的《2024年度交易回顾》报告，2024年肿瘤项目再次成为药企合作与授权交易的最核心驱动力，不论是交易数量还是潜在交易金额，都遥遥领先其他治疗领域。从2025年迄今为止的大型制药公司并购与授权交易来看，肿瘤学资产仍然是最受关注的内容。2024年，全球生物医药行业共达成690项合作交易（涵盖许可协议、研发合作及资产出售），较2023年的718项略降4%。其中有286项交易披露了潜在金额，总潜在价值达到了1919亿美元，相比2023年的1869亿美元小幅上涨3%。01肿瘤：交易总量与金额双冠王2024年共有245项交易涉及肿瘤相关资产，占全年所有交易的约36%，远超其他领域（图1）。从交易总潜在价值来看，肿瘤领域表现更加突出（图2）。肿瘤相关交易总潜在价值达到了786亿美元，占全年所有披露金额的41%，几乎是排名第二的神经/精神类疾病（408亿美元）的两倍。其他主要领域的总潜在交易金额还包括自免疫/炎症（289亿美元 ）和代谢疾病（318亿美元）等。图1. 2024年制药业交易数量分布图（图片来源：Citeline）图2. 2024年制药业交易金额数量分布图（图片来源：Citeline）尽管其他领域逐渐崛起，但肿瘤仍是产业资金最为集中、最被看好的板块。如果以“潜在交易金额跨越10亿美元门槛作为衡量标准，2024年共有31项肿瘤相关交易达到这一标准 ，继续保持领先。之后依次是神经疾病（14项）、免疫与炎症学（12项）、其他领域（如过敏、内分泌、血液、呼吸等，共9项）、未标注治疗领域（9项）。02大额交易由肿瘤学主导制药业2024年的大型交易主要仍由肿瘤学资产引导：· BMS 与 Prime Medicine 达成近36亿美元协议，用于开发新一代CAR-T细胞疗法（涵盖免疫与肿瘤）。· 默沙东与LaNova Medicines达成32.9亿美元协议，合作开发PD-1/VEGF双特异性抗体，用于实体瘤。· 诺华与Dren Bio签署30亿美元合作协议，联合开发双特异性抗体，应用于肿瘤治疗。032025年大型制药公司交易在2025年前四个月由大型制药公司主导的医药领域资产交易中，肿瘤学仍然无疑是当之无愧的核心焦点。从交易数量来看，肿瘤学相关并购与授权共计13笔，占总交易的34%，位列所有适应症首位，显示出在研发策略和业务拓展中，肿瘤领域仍是大型药企投入最集中的战场之一（图3）。图3. 2025年前四月大型制药公司资产交易数量的适应症关联图不仅如此，肿瘤学资产在交易金额上的表现同样抢眼。其总交易金额达116.8亿美元（交易金额包括潜在里程碑付款），占比22%，在所有疾病领域中位列第二，仅次于神经病学（图4）。这种“量质齐优”的表现，反映出肿瘤资产不仅获得更多关注，也具备显著的商业价值与战略地位。图4. 2025年前四月大型制药公司资产交易金额的适应症关联图从交易结构来看，大型药企在肿瘤学的投入呈现出多样化靶点与模态布局的特征，包括小分子、抗体偶联药物（ADC）、CAR-T细胞疗法、双/三特异性抗体等。其中，礼来并购Scorpion以获取PI3Kα抑制剂STX-478、艾伯维与Xilio及Neomorph达成多项早期授权、BMS收购2seventy bio获得CAR-T疗法Abecma，以及罗氏与信达围绕DLL3-ADC的合作，均表明从临床前到上市，肿瘤资产正贯穿各个开发阶段，覆盖多种创新路径。此外，值得注意的是，部分交易如艾伯维-先声、BI-Oxford及艾伯维-Neomorph已开始涉足肿瘤与炎症/免疫交叉领域，进一步拓展免疫肿瘤学边界，体现出药企对于多适应症协同潜力的高度重视。04待价而沽的肿瘤高潜力资产据 Evaluate 数据预测，至 2030 年，肿瘤药物的全球市场规模将超过下一个治疗领域的两倍，牢牢占据市场核心地位。在这一竞争激烈、不断细分的领域，创新需求持续高涨，一批尚未达成合作协议的临床阶段资产也显示出巨大商业潜力（表1）。表1.  高净现值未交易临床肿瘤学资产根据 Evaluate 的预测数据，在所有未达成合作协议的临床阶段肿瘤资产中，Caribou Biosciences拥有的两项 CAR-T 疗法：CB010 和 CB011 的净现值（NPV）排名最高，分别处于非霍奇金淋巴瘤与多发性骨髓瘤适应症的一期临床阶段。Caribou 的差异化策略在于其 PD-1 基因敲除机制（CB010）以及 HLA 匹配优化路径，解决现有异体CAR-T 疗法在耐久性方面的短板。虽然CB010的关键性试验启动时间推迟至2025年底曾引发市场疑虑，但如果HLA匹配数据积极，仍有望成为该领域中值得关注的潜力项目。除了细胞疗法，非肌层浸润性膀胱癌（NMIBC）领域也涌现出尚未建立合作的潜力管线。Aura Biosciences开发的病毒样药物缀合物（VDC）belzupacap sarotalocan（bel-sar），已进入III期（用于脉络膜黑色素瘤）和I期（用于膀胱癌）临床阶段。该产品已获得 FDA 对其关键性试验 CoMpass 的特殊方案评估（SPA）确认，预计2027年有望进入市场。Aura 近期宣布将在膀胱癌中加速推进bel-sar，以抢占高风险人群之外的低至中风险治疗空白地带。ALK阳性非小细胞肺癌（NSCLC）赛道上，Nuvalent开发的 ALK 抑制剂 neladalkib（NVL-655）表现亮眼。该产品正在开展 ALKAZAR 头对头试验，挑战当前标准疗法 alectinib，并已于2024年获得 FDA 突破性疗法认定。其在二/三线患者中的疗效和安全性数据也在ESMO会议上初步亮相。尽管 Nuvalent 的市值已超过40亿美元，但公司尚未引入商业化合作方，未来仍有通过交易放大管线价值的空间。在 PSMA 靶点这一竞争日趋激烈的领域，Janux Therapeutics旗下的 JNX007 凭借其“遮蔽型T细胞活化剂”技术受到关注。该产品目前处于一期临床阶段，已在五线治疗的前列腺癌患者中展示出良好的安全性与疗效信号，公司计划进一步拓展至三线甚至更早线治疗，以抢占先机。尽管 Janux 的估值已升至15亿美元以上，但其仍未与大药企建立合作，成为该赛道中少数尚保持独立推进的创新平台之一。由此可见，虽然当前大额交易多数集中于已上市或进入后期临床阶段的项目，但从资产储备角度看，仍有一批临床阶段的未合作肿瘤资产在估值、技术差异化、适应症稀缺性等多个维度具备较强吸引力。这些项目或将在未来1-2年内成为大型药企战略补位的关键棋子，推动下一轮交易高潮。在资本更加理性、合作方更趋谨慎的背景下，肿瘤领域依旧凭借其市场体量、未满足需求与技术创新三重驱动，稳居生物医药交易的核心位置。无论是CAR-T 等细胞疗法的不断演进，还是新一代靶向药与双抗平台的技术突破，都为投资者与药企提供了持续的想象空间。值得关注的是，那些尚未“名花有主”的早期肿瘤资产，正逐步在数据成熟与机制验证中释放出其真实潜力。随着2025年前后多项关键性临床节点的临近，这些项目或将成为大型药企加码布局、重塑产品管线的关键“变量”。肿瘤赛道的下一轮交易热潮，或许就将从这些隐而未发的高潜力资产中开启。往期推荐1医健企业前沿动态2医健行业BD/出海/投融资洞察___*声明：本文仅为作者观点，不构成任何投资建议，且非治疗方案推荐。Ref.Haas, J. Cancer Retains Top Spots In Alliance Deal Volume, Value. Scrip. 18. 04. 2025.Haas, J. Deal Watch: Sarepta Targets RNAi In Broad Collaboration With Arrowhead. Scrip. 29. 11. 2024.Elmhirst, E. Oncology’s Most Eligible Unpartnered Assets. Scrip. 18. 04. 2025.2025 biotech deals tracker: the latest partnerships and M&A activities. Labiotech. Retrieved on 03. 05. 2025.Pannu, A.  Big Pharma M&A and licensing deal trends in 2025. LinkedIn.关于贝壳社贝壳社是国内领先的医健创新创业服务平台，构建了"产业空间+创业教育+投资孵化+资本运作"四位一体服务体系，为医健领域创业企业提供全周期赋能。通过深度挖掘高成长项目、精准匹配产业资源及全球化生态网络，覆盖企业从孵化培育到加速发展的全链路，重点提供包括空间落地、创业培训、资本运作及跨境资源链接服务。贝壳社以加速科学技术成果转化与产业升级为目标，致力于成为医健领域的孵化器、加速器、连接器。

CAMBRIDGE, Mass.--(BUSINESS WIRE)--2seventy bio, Inc. (Nasdaq: TSVT), today reported financial results and recent highlights for the first quarter ended March 31, 2025. “We started 2seventy with a singular focus on harnessing the power of cell therapy to deliver more time for people living with cancer,” said Chip Baird, chief executive officer, 2seventy bio. “Over the past four years we have delivered on that mission, treating thousands of multiple myeloma patients with Abecma and developing an R&D pipeline of innovative treatments for liquid and solid tumors that we transitioned to Regeneron and Novo Nordisk. With the anticipated closing of the acquisition of 2seventy by Bristol Myers Squibb (BMS) this quarter, we will continue to deliver Abecma® (idecabtagene vicleucel; ide-cel) as part of BMS. I would like to express my deep gratitude to our current and former team members and more broadly the dedicated community of patients, scientists, providers, partners, and investors who worked tirelessly to deliver more time for patients.” On March 10, 2025, 2seventy bio announced that it had entered into a definitive merger agreement to be acquired by BMS. Under the terms of the agreement, BMS commenced a tender offer on April 14, 2025 to acquire all outstanding shares of common stock of 2seventy bio at a price of $5.00 per share in an all-cash transaction. 2seventy bio’s Board of Directors unanimously recommended that 2seventy bio stockholders tender their shares in the tender offer. The waiting period applicable to the tender offer under the Hart-Scott-Rodino Antitrust Improvements Act of 1976 (HSR Act) expired at 11:59 p.m. Eastern Time on May 2, 2025. The transaction remains subject to the tender of a majority of the outstanding shares of 2seventy bio’s common stock, as well as other customary closing conditions. Unless the tender offer is extended, the offer and withdrawal rights will expire at midnight (New York City time), one minute after 11:59 p.m. New York City time, on May 12, 2025. ABECMA COMMERCIAL HIGHLIGHTS First quarter Abecma U.S. sales, as reported by BMS, were $58.6 million. 2seventy bio and BMS continue to focus on competitively differentiating Abecma’s safety and efficacy profile supported by the strength of the KarMMa-3 and real-world data. 2seventy bio and BMS share equally in all profits and losses related to development, manufacturing, and commercialization of Abecma in the United States. 2seventy bio reported collaboration revenue of approximately $19.1 million related to the collaboration with BMS for the three months ended March 31, 2025. SELECT FIRST QUARTER FINANCIAL RESULTS Total revenues were $22.9 million for the three months ended March 31, 2025, compared to $12.4 million for the three months ended March 31, 2024. Research and development expenses were $5.4 million for the three months ended March 31, 2025, compared to $43.9 million for the three months ended March 31, 2024. Selling, general and administrative expenses were $14.9 million for the three months ended March 31, 2025, compared to $12.7 million for the three months ended March 31, 2024. There was no loss on assets held for sale for the three months ended March 31, 2025, compared to a $5.0 million loss on assets held for sale for the three months ended March 31, 2024. Net income was $0.5 million for the three months ended March 31, 2025, compared to net loss of $52.7 million for the three months ended March 31, 2024. Cash, cash equivalents, and marketable securities totaled $173.4 million as of March 31, 2025. Merger Agreement Details and Path to Completion Following the successful closing of the tender offer, BMS will acquire all remaining shares of 2seventy bio common stock that are not tendered in the tender offer through a second-step merger at the same price in the tender offer of $5.00 per share. Following the completion of this transaction, 2seventy bio’s common stock will no longer be listed for trading on Nasdaq. In connection with the execution of the merger agreement, certain stockholders of 2seventy bio owning approximately 6.0% of the outstanding shares of 2seventy bio’s common stock entered into tender and support agreements, pursuant to which they agreed to tender all of their shares in the offer. In light of the announced transaction, 2seventy bio will not be hosting an earnings conference call or providing financial guidance for 2025. ABECMA U.S. INDICATION ABECMA is a B-cell maturation antigen (BCMA)-directed genetically modified autologous T cell immunotherapy indicated for the treatment of adult patients with relapsed or refractory multiple myeloma after two or more prior lines of therapy including an immunomodulatory agent, a proteasome inhibitor, and an anti-CD38 monoclonal antibody. U.S. Important Safety Information BOXED WARNING: CYTOKINE RELEASE SYNDROME, NEUROLOGIC TOXICITIES, HLH/MAS, PROLONGED CYTOPENIA and SECONDARY HEMATOLOGICAL MALIGNANCIES Cytokine Release Syndrome (CRS), including fatal or life-threatening reactions, occurred in patients following treatment with ABECMA. Do not administer ABECMA to patients with active infection or inflammatory disorders. Treat severe or life-threatening CRS with tocilizumab or tocilizumab and corticosteroids. Neurologic Toxicities, which may be severe or life-threatening, occurred following treatment with ABECMA, including concurrently with CRS, after CRS resolution, or in the absence of CRS. Monitor for neurologic events after treatment with ABECMA. Provide supportive care and/or corticosteroids as needed. Hemophagocytic Lymphohistiocytosis/Macrophage Activation Syndrome (HLH/MAS) including fatal and life-threatening reactions, occurred in patients following treatment with ABECMA. HLH/MAS can occur with CRS or neurologic toxicities. Prolonged Cytopenia with bleeding and infection, including fatal outcomes following stem cell transplantation for hematopoietic recovery, occurred following treatment with ABECMA. T cell malignancies have occurred following treatment of hematologic malignancies with BCMA- and CD19-directed genetically modified autologous T cell immunotherapies, including ABECMA ABECMA is available only through a restricted program under a Risk Evaluation and Mitigation Strategy (REMS) called the ABECMA REMS. Warnings and Precautions: Early Death: In KarMMa-3, a randomized (2:1), controlled trial, a higher proportion of patients experienced death within 9 months after randomization in the ABECMA arm (45/254; 18%) compared to the standard regimens arm (15/132; 11%). Early deaths occurred in 8% (20/254) and 0% prior to ABECMA infusion and standard regimen administration, respectively, and 10% (25/254) and 11% (15/132) after ABECMA infusion and standard regimen administration, respectively. Out of the 20 deaths that occurred prior to ABECMA infusion, 15 occurred from disease progression, 3 occurred from adverse events and 2 occurred from unknown causes. Out of the 25 deaths that occurred after ABECMA infusion, 10 occurred from disease progression, 11 occurred from adverse events, and 4 occurred from unknown causes. Cytokine Release Syndrome (CRS): CRS, including fatal or life-threatening reactions, occurred following treatment with ABECMA. Among patients receiving ABECMA for relapsed refractory multiple myeloma in the KarMMa and KarMMa-3 studies (N=349), CRS occurred in 89% (310/349), including ≥ Grade 3 CRS (Lee grading system) in 7% (23/349) of patients and Grade 5 CRS in 0.9% (3/349) of patients. The median time-to-onset of CRS, any grade, was 1 day (range: 1 to 27 days), and the median duration of CRS was 5 days (range: 1 to 63 days). In the pooled studies, the rate of ≥Grade 3 CRS was 10% (7/71) for patients treated in dose range of 460 to 510 x 106 CAR-positive T cells and 5.4% (13/241) for patients treated in dose range of 300 to 460 x 106 CAR-positive T cells. The most common manifestations of CRS (greater than or equal to 10%) included pyrexia (87%), hypotension (30%), tachycardia (26%), chills (19%), hypoxia (16%). Grade 3 or higher events that may be associated with CRS include hypotension, hypoxia, hyperbilirubinemia, hypofibrinogenemia, ARDS, atrial fibrillation, hepatocellular injury, metabolic acidosis, pulmonary edema, coagulopathy, renal failure, multiple organ dysfunction syndrome and HLH/MAS. Identify CRS based on clinical presentation. Evaluate for and treat other causes of fever, hypoxia, and hypotension. CRS has been reported to be associated with findings of HLH/MAS, and the physiology of the syndromes may overlap. HLH/MAS is a potentially life-threatening condition. In patients with progressive symptoms of CRS or refractory CRS despite treatment, evaluate for evidence of HLH/MAS. Of the 349 patients who received ABECMA in clinical trials, 226 (65%) patients received tocilizumab; 39% (135/349) received a single dose, while 26% (91/349) received more than 1 dose of tocilizumab. Overall, 24% (82/349) of patients received at least 1 dose of corticosteroids for treatment of CRS. Almost all patients who received corticosteroids for CRS also received tocilizumab. For patients treated in dose range of 460 to 510 x 106 CAR-positive T cells, 76% (54/71) of patients received tocilizumab and 35% (25/71) received at least 1 dose of corticosteroids for treatment of CRS. For patients treated in dose range of 300 to 460 x 106 CAR-positive T cells, 63% (152/241) of patients received tocilizumab and 20% (49/241) received at least 1 dose of corticosteroid for treatment of CRS. Monitor patients at least daily for 7 days following ABECMA infusion at the REMS-certified healthcare facility for signs or symptoms of CRS and monitor patients for signs or symptoms of CRS for at least 4 weeks after ABECMA infusion. At the first sign of CRS, institute treatment with supportive care, tocilizumab and/or corticosteroids as indicated. Ensure that a minimum of 2 doses of tocilizumab are available prior to infusion of ABECMA. Counsel patients to seek immediate medical attention should signs or symptoms of CRS occur at any time. Neurologic Toxicities: Neurologic toxicities, including immune-effector cell-associated neurotoxicity (ICANS), which may be severe or life- threatening, occurred concurrently with CRS, after CRS resolution, or in the absence of CRS following treatment with ABECMA. In patients receiving ABECMA in the KarMMa and KarMMa-3 studies, CAR T cell-associated neurotoxicity occurred in 40% (139/349), including Grade 3 in 4% (14/349) and Grade 4 in 0.6% (2/349) of patients. The median time to onset of neurotoxicity was 2 days (range: 1 to 148 days). The median duration of CAR T cell-associated neurotoxicity was 8 days (range: 1 to 720 days) in all patients including those with ongoing neurologic events at the time of death or data cut off. CAR T cell-associated neurotoxicity resolved in 123 of 139 (88%) patients and median time to resolution was 5 days (range: 1 to 245 days). 134 out of 349 (38%) patients with neurotoxicity had CRS. The onset of neurotoxicity during CRS was observed in 93 patients, before the onset of CRS in 12 patients, and after the CRS event in 29 patients. The rate of Grade 3 or 4 CAR T cell-associated neurotoxicity was 5.6% (4/71) and 3.7% (9/241) for patients treated in dose range of 460 to 510 x 106 CAR-positive T cells and 300 to 460 x 106 CAR-positive T cells, respectively. The most frequent (greater than or equal to 5%) manifestations of CAR T cell-associated neurotoxicity include encephalopathy (21%), headache (15%), dizziness (8%), delirium (6%), and tremor (6%). At the safety update for KarMMa-3 study, one patient developed fatal neurotoxicity 43 days after ABECMA. In KarMMa, one patient had ongoing Grade 2 neurotoxicity at the time of death. Two patients had ongoing Grade 1 tremor at the time of data cutoff. Cerebral edema has been associated with ABECMA in a patient in another study in multiple myeloma. Grade 3 myelitis and Grade 3 parkinsonism have occurred after treatment with ABECMA in another study in multiple myeloma. Monitor patients at least daily for 7 days following ABECMA infusion at the REMS-certified healthcare facility for signs or symptoms of neurologic toxicities and monitor patients for signs or symptoms of neurologic toxicities for at least 4 weeks after ABECMA infusion and treat promptly. Rule out other causes of neurologic symptoms. Neurologic toxicity should be managed with supportive care and/or corticosteroids as needed. Counsel patients to seek immediate medical attention should signs or symptoms occur at any time. Hemophagocytic Lymphohistiocytosis (HLH)/Macrophage Activation Syndrome (MAS): In patients receiving ABECMA in the KarMMa and KarMMa-3 studies, HLH/MAS occurred in 2.9% (10/349) of patients. All events of HLH/MAS had onset within 10 days of receiving ABECMA, with a median onset of 6.5 days (range: 4 to 10 days) and occurred in the setting of ongoing or worsening CRS. Five patients with HLH/MAS had overlapping neurotoxicity. The manifestations of HLH/MAS include hypotension, hypoxia, multiple organ dysfunction, renal dysfunction and cytopenia. In KarMMa-3, one patient had Grade 5, two patients had Grade 4 and two patients had Grade 3 HLH/MAS. The patient with Grade 5 HLH/MAS also had Grade 5 candida sepsis and Grade 5 CRS. In another patient who died due to stroke, the Grade 4 HLH/MAS had resolved prior to death. Two cases of Grade 3 and one case of Grade 4 HLH/MAS had resolved. In KarMMa, one patient treated in the 300 x 106 CAR-positive T cells dose cohort developed fatal multi-organ HLH/MAS with CRS. In another patient with fatal bronchopulmonary aspergillosis, HLH/MAS was contributory to the fatal outcome. Three cases of Grade 2 HLH/MAS resolved. HLH/MAS is a potentially life-threatening condition with a high mortality rate if not recognized early and treated. Treatment of HLH/MAS should be administered per institutional guidelines. ABECMA REMS: Due to the risk of CRS and neurologic toxicities, ABECMA is available only through a restricted program under a Risk Evaluation and Mitigation Strategy (REMS) called the ABECMA REMS. Further information is available at www.AbecmaREMS.com or contact Bristol-Myers Squibb at 1-866-340-7332. Hypersensitivity Reactions: Allergic reactions may occur with the infusion of ABECMA. Serious hypersensitivity reactions, including anaphylaxis, may be due to dimethyl sulfoxide (DMSO) in ABECMA. Infections: ABECMA should not be administered to patients with active infections or inflammatory disorders. Severe, life-threatening, or fatal infections occurred in patients after ABECMA infusion. In all patients receiving ABECMA in the KarMMa and KarMMa-3 studies, infections (all grades) occurred in 61% of patients. Grade 3 or 4 infections occurred in 21% of patients. Grade 3 or 4 infections with an unspecified pathogen occurred in 12%, viral infections in 7%, bacterial infections in 4.3%, and fungal infections in 1.4% of patients. Overall, 15 patients had Grade 5 infections (4.3%); 8 patients (2.3%) with infections of pathogen unspecified, 3 patients (0.9%) with fungal infections, 3 patients (0.9%) with viral infections, and 1 patient (0.3%) with bacterial infection. Monitor patients for signs and symptoms of infection before and after ABECMA infusion and treat appropriately. Administer prophylactic, pre-emptive, and/or therapeutic antimicrobials according to standard institutional guidelines. Febrile neutropenia was observed in 38% (133/349) of patients after ABECMA infusion and may be concurrent with CRS. In the event of febrile neutropenia, evaluate for infection and manage with broad-spectrum antibiotics, fluids, and other supportive care as medically indicated. Viral Reactivation: Cytomegalovirus (CMV) infection resulting in pneumonia and death has occurred following ABECMA administration. Monitor and treat for CMV reactivation in accordance with clinical guidelines. Hepatitis B virus (HBV) reactivation, in some cases resulting in fulminant hepatitis, hepatic failure, and death, can occur in patients treated with drugs directed against plasma cells. Perform screening for CMV, HBV, hepatitis C virus (HCV), and human immunodeficiency virus (HIV) in accordance with clinical guidelines before collection of cells for manufacturing. Consider antiviral therapy to prevent viral reactivation per local institutional guidelines/clinical practice. Prolonged Cytopenias: In patients receiving ABECMA in the KarMMa and KarMMa-3 studies, 40% of patients (139/349) experienced prolonged Grade 3 or 4 neutropenia and 42% (145/349) experienced prolonged Grade 3 or 4 thrombocytopenia that had not resolved by Month 1 following ABECMA infusion. In 89% (123/139) of patients who recovered from Grade 3 or 4 neutropenia after Month 1, the median time to recovery from ABECMA infusion was 1.9 months. In 76% (110/145) of patients who recovered from Grade 3 or 4 thrombocytopenia, the median time to recovery was 1.9 months. Five patients underwent stem cell therapy for hematopoietic reconstitution due to prolonged cytopenia. The rate of Grade 3 or 4 thrombocytopenia was 62% (44/71) and 56% (135/241) for patients treated in dose range of 460 to 510 x 106 CAR-positive T cells and 300 to 460 x 106 CAR-positive T cells, respectively. Monitor blood counts prior to and after ABECMA infusion. Manage cytopenia with myeloid growth factor and blood product transfusion support according to local institutional guidelines. Hypogammaglobulinemia: In all patients receiving ABECMA in the KarMMa and KarMMa-3 studies, hypogammaglobulinemia was reported as an adverse event in 13% (46/349) of patients; laboratory IgG levels fell below 500 mg/dL after infusion in 37% (130/349) of patients treated with ABECMA. Hypogammaglobulinemia either as an adverse reaction or laboratory IgG level below 500 mg/dL after infusion occurred in 45% (158/349) of patients treated with ABECMA. Forty-one percent of patients received intravenous immunoglobulin (IVIG) post-ABECMA for serum IgG <400 mg/dL. Monitor immunoglobulin levels after treatment with ABECMA and administer IVIG for IgG <400 mg/dl. Manage appropriately per local institutional guidelines, including infection precautions and antibiotic or antiviral prophylaxis. Use of Live Vaccines: The safety of immunization with live viral vaccines during or after ABECMA treatment has not been studied. Vaccination with live virus vaccines is not recommended for at least 6 weeks prior to the start of lymphodepleting chemotherapy, during ABECMA treatment, and until immune recovery following treatment with ABECMA. Secondary Malignancies: Patients treated with ABECMA may develop secondary malignancies. In KarMMa-3, myeloid neoplasms (four cases of myelodysplastic syndrome and one case of acute myeloid leukemia) occurred in 2.2% (5/222) of patients following treatment with ABECMA compared to none in the standard regimens arm at the time of the safety update. The median time to onset of myeloid neoplasm from ide-cel infusion was 338 days (Range: 277 to 794 days). Three of these five patients have died following the development of myeloid neoplasm. One out of the five cases of myeloid neoplasm occurred after initiation of subsequent antimyeloma therapy. T cell malignancies have occurred following treatment of hematologic malignancies with BCMA- and CD19-directed genetically modified autologous T cell immunotherapies, including ABECMA. Mature T cell malignancies, including CAR-positive tumors, may present as soon as weeks following infusion, and may include fatal outcomes. Monitor life-long for secondary malignancies. In the event that a secondary malignancy occurs, contact Bristol-Myers Squibb at 1‑888‑805‑4555 for reporting and to obtain instructions on collection of patient samples for testing of secondary malignancy. Effects on Ability to Drive and Operate Machinery: Due to the potential for neurologic events, including altered mental status or seizures, patients receiving ABECMA are at risk for altered or decreased consciousness or coordination in the 8 weeks following ABECMA infusion. Advise patients to refrain from driving and engaging in hazardous occupations or activities, such as operating heavy or potentially dangerous machinery, during this initial period. Adverse Reactions: The most common nonlaboratory adverse reactions (incidence greater than or equal to 20%) include pyrexia, CRS, hypogammaglobulinemia, infections – pathogen unspecified, musculoskeletal pain, fatigue, febrile neutropenia, hypotension, tachycardia, diarrhea, nausea, headache, chills, upper respiratory tract infection, encephalopathy, edema, dyspnea and viral infections. Please see full Prescribing Information, including Boxed WARNINGS and Medication Guide. About Abecma Abecma is being jointly developed and commercialized in the U.S. as part of a Co-Development, Co-Promotion, and Profit Share Agreement between BMS and 2seventy bio. BMS assumes sole responsibility for Abecma drug product manufacturing and commercialization outside of the U.S. The companies’ clinical development program for Abecma includes ongoing clinical studies (KarMMa-2, KarMMa-3) in earlier lines of treatment for patients with multiple myeloma. For more information visit clinicaltrials.gov. About 2seventy bio Our name, 2seventy bio, reflects why we do what we do - TIME. Cancer rips time away, and our goal is to work at the maximum speed of translating human thought into action – 270 miles per hour – to give the people we serve more time. With a deep understanding of the human body’s immune response to tumor cells and how to translate cell therapies into practice, we’re applying this knowledge to deliver the first FDA-approved CAR T cell therapy for multiple myeloma to as many patients as possible. Importantly, we remain focused on accomplishing our mission by staying genuine and authentic to our “why” and keeping our people and culture top of mind every day. For more information, visit www.2seventybio.com. Follow 2seventy bio on social media: X (Twitter) and LinkedIn. 2seventy bio is a trademark of 2seventy bio, Inc. Cautionary Note Regarding Forward-Looking Statements This release contains “forward-looking statements” within the meaning of applicable laws and regulations. These statements include, but are not limited to, statements regarding 2seventy bio’s financial performance, statements regarding the proposed acquisition of 2seventy bio by BMS, the expected timetable for completing the transaction, future opportunities for the combined businesses, the expected benefits of BMS’s acquisition of 2seventy bio and the development and commercialization of Abecma. These statements may be identified by the fact they use words such as “should,” “could,” “expect,” “anticipate,” “estimate,” “target,” “may,” “project,” “guidance,” “intend,” “plan,” “believe,” “will” and other words and terms of similar meaning and expression in connection with any discussion of future operating or financial performance, although not all forward-looking statements contain such terms. These statements are only predictions, and such forward-looking statements are based on current expectations and involve inherent risks, assumptions and uncertainties, including internal or external factors that could delay, divert or change any of them, that are difficult to predict, may be beyond 2seventy bio’s control and could cause actual outcomes and results to differ materially from those expressed in, or implied by, the forward-looking statements. Actual results may differ materially because of numerous risks and uncertainties including with respect to (i) the timing of the tender offer and subsequent merger, (ii) the number of shares of 2seventy bio common stock that will be tendered in the tender offer, (iii) the risk that the expected benefits or synergies of the acquisition will not be realized, (iv) the risk that legal proceedings may be instituted related to the merger agreement, (v) any competing offers or acquisition proposals for 2seventy bio, (vi) the possibility that various conditions to the consummation of the tender offer or the acquisition may not be satisfied or waived, including that a governmental entity may prohibit, delay or refuse to grant approval for the consummation of the offer or the acquisition and (vii) unanticipated difficulties or expenditures relating to the proposed acquisition, including the response of business partners and competitors to the announcement of the proposed acquisition or difficulties in employee retention as a result of the announcement and pendency of the proposed acquisition. No forward-looking statement can be guaranteed. Forward-looking statements in this press release should be evaluated together with the many risks and uncertainties that affect BMS’s business and market, particularly those identified in the cautionary statement and risk factors discussion in BMS’s Annual Report on Form 10-K for the year ended December 31, 2024, and its subsequent Quarterly Reports on Form 10-Q, and 2seventy bio’s business, particularly those identified in the risk factors discussion in 2seventy bio’s Annual Report on Form 10-K for the year ended December 31, 2024, and its subsequent Quarterly Reports on Form 10-Q, as well as other documents that may be filed by BMS or 2seventy bio from time to time with the SEC. 2seventy bio undertakes no obligation to publicly update any forward-looking statement, whether as a result of new information, future events or otherwise, except to the extent required by law. The forward-looking statements made in this press release relate only to events as of the date on which the statements are made and readers are cautioned not to place undue reliance on such statements. Additional Information and Where to Find It The tender offer described in this document commenced on April 14, 2025. This document is for informational purposes only and is neither an offer to purchase nor a solicitation of an offer to sell any shares of the common stock of 2seventy bio or any other securities, nor is it a substitute for the tender offer materials described herein. A tender offer statement on Schedule TO, including an offer to purchase, a letter of transmittal and related documents, was filed by BMS and Daybreak Merger Sub Inc., a wholly owned indirect subsidiary of BMS, with the Securities and Exchange Commission (SEC), and a solicitation/recommendation statement on Schedule 14D-9 was filed by 2seventy bio with the SEC. The offer to purchase shares of 2seventy bio common stock will only be made pursuant to the offer to purchase, the letter of transmittal and related documents filed as a part of the Schedule TO. INVESTORS AND SECURITY HOLDERS ARE URGED TO CAREFULLY READ BOTH THE TENDER OFFER MATERIALS (INCLUDING AN OFFER TO PURCHASE, A LETTER OF TRANSMITTAL AND RELATED DOCUMENTS) AND THE SOLICITATION/RECOMMENDATION STATEMENT ON SCHEDULE 14D-9 REGARDING THE OFFER, AS THEY MAY BE AMENDED FROM TIME TO TIME, BECAUSE THEY CONTAIN IMPORTANT INFORMATION THAT INVESTORS AND SECURITY HOLDERS SHOULD CONSIDER BEFORE MAKING ANY DECISION REGARDING TENDERING THEIR SECURITIES. Investors and security holders may obtain a free copy of the offer to purchase, the related letter of transmittal, certain other tender offer documents and the solicitation/recommendation statement and other documents filed with the SEC on the SEC’s website at www.sec.gov or by directing such requests to the information agent for the offer. The offer to purchase and related tender offer documents may also be obtained for free on BMS’ website at www.bms.com/investors or 2seventy bio’s website at www.ir.2seventybio.com. In addition, BMS and 2seventy bio each files annual, quarterly and current reports and other information with the SEC, which are also available to the public at no charge at www.sec.gov. 2seventy bio, Inc. Condensed Consolidated Statements of Operations and Comprehensive Income (Loss) (unaudited) (in thousands, except per share data) 2025 2024 $ 3,773 $ 7,721 19,144 4,714 21 - 22,938 12,435 5,399 43,931 5,153 3,269 14,849 12,659 - 1,230 57 4,230 - (1,730 ) 25,458 63,589 (2,520 ) (51,154 ) 2,321 2,861 681 646 - (5,026 ) 482 (52,673 ) - - $ 482 $ (52,673 ) $ 0.01 $ (1.01 ) $ 0.01 $ (1.01 ) 53,055 52,071 53,433 52,071 2seventy bio, Inc. Condensed Consolidated Balance Sheet Data (unaudited) (in thousands) $ 173,362 $ 183,621 480,005 479,510 266,044 268,704 213,961 210,806