UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2022 OR TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 ☐ For the transition period from _________ to ________ Commission file number 001-40791 2seventy bio, Inc. (Exact name of registrant as specified in its charter) (State or other jurisdiction of incorporati ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2022 OR TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 ☐ For the transition period from _________ to ________ Commission file number 001-40791 2seventy bio, Inc. (Exact name of registrant as specified in its charter) Delaware 86-3658454 (State or other jurisd ...

Financial Performance - The company reported a net loss of $292.2 million for the year ended December 31, 2021, with previous losses of $120.1 million in 2020 and $320.6 million in 2019, indicating ongoing financial challenges [224]. - As of December 31, 2021, the company held cash, cash equivalents, and marketable securities totaling $362.2 million, which is expected to fund operations for at least the next twelve months [228]. - The company anticipates continued significant operating losses as it invests in research and development, including additional clinical trials for ABECMA [226]. - Future revenues will depend on market acceptance and reimbursement for ABECMA and any future products, which are still in development [225]. - The company’s revenues will depend on research and development funding and milestone payments from collaboration agreements, which may vary significantly from quarter to quarter [392]. - The company’s operating results may fluctuate significantly, making future performance difficult to predict and potentially leading to stock price volatility [391]. Revenue Generation and Commercialization Challenges - The company has not recognized any revenue from product sales to date, relying on collaboration and out-licensing arrangements for income [222]. - The company faces challenges in commercial scale manufacturing and sales and marketing activities necessary for ABECMA's commercialization [223]. - The potential market for ABECMA and future products may be smaller than anticipated, affecting revenue generation and market share [236]. - The commercialization of ABECMA is primarily the responsibility of BMS, and there is no guarantee of its successful commercialization, impacting potential revenue generation [334]. - Establishing a commercial sales force and obtaining adequate pricing and reimbursement for ABECMA are critical challenges that the company must address [336]. - The company may face reimbursement challenges, particularly for novel therapies like CAR-T cell therapies, which could limit profitability [343]. Regulatory and Clinical Trial Risks - The ongoing COVID-19 pandemic has caused operational disruptions, affecting clinical studies and the commercialization efforts of ABECMA, which is co-developed with BMS [218]. - Regulatory agencies may experience disruptions due to the pandemic, potentially delaying the review and approval processes for the company's clinical studies [220]. - The company faces high risks of failure in clinical trials, particularly for early-stage product candidates, due to variability in safety and efficacy results [233]. - Recruitment challenges for clinical studies may lead to delays, impacting the timeline for obtaining regulatory approvals [234]. - The FDA typically requires two pivotal trials for biologics license applications, but may approve based on one trial under certain circumstances [242]. - The regulatory approval process is lengthy and unpredictable, with no guarantee that any product candidate will receive approval [262]. Manufacturing and Compliance Issues - The company relies on third-party manufacturers for production, which reduces control over manufacturing and compliance with regulations [287]. - Delays in third-party manufacturing could impact the completion of preclinical and clinical studies, as well as the commercialization of products [288]. - Regulatory compliance is critical; failure to maintain it could result in sanctions, including refusal of product approvals [294]. - The complexity of manufacturing processes necessitates regular evaluations and potential changes, which may incur additional costs and delays [295]. - The company must ensure that third-party manufacturers meet quality standards and regulatory requirements, which could involve costly and time-consuming remedial measures [293]. Intellectual Property and Legal Risks - Intellectual property rights are crucial for competitive advantage; challenges in obtaining or protecting these rights could adversely affect the business [303]. - There is a substantial risk of litigation related to patent infringement, which could delay development and commercialization efforts [309]. - The company may need to obtain licenses from third parties for product candidates, and failure to do so could significantly harm business operations [319]. - The company faces significant challenges in protecting its intellectual property rights globally, with costs for filing and defending patents being prohibitively expensive [330]. - Recent U.S. patent law changes and Supreme Court rulings have narrowed patent protection, increasing uncertainty regarding the ability to obtain and enforce patents [329]. Competition and Market Conditions - The company faces intense competition in gene therapy development, with competitors having greater financial and technical resources, which may adversely affect its ability to commercialize products [368]. - Legislative changes, such as the Affordable Care Act, have significantly impacted the U.S. pharmaceutical industry, including increased Medicaid rebates and new discount programs [378]. - The implementation of healthcare reform measures may lead to more rigorous coverage criteria and additional downward pressure on product pricing, potentially harming future revenues [383]. Employee and Operational Risks - The company employed 437 full-time employees as of March 1, 2022, with plans for future expansion that may require significant capital expenditures [396]. - The loss of key management and scientific personnel could delay product development and harm business operations [389]. - Employee misconduct poses a risk, including violations of FDA regulations and insider trading, which could result in significant fines and reputational damage [404]. Compliance with Healthcare Laws - The company is subject to various federal and state healthcare fraud and abuse laws, including the Anti-Kickback Statute and the False Claims Act, which impose severe penalties for violations [357]. - The FDA and other regulatory authorities impose strict requirements on product promotion, and violations can lead to substantial civil and criminal fines [354]. - The company is developing a compliance program to prevent non-compliance with healthcare laws, which may involve substantial costs [362].

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2021 OR TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 ☐ For the transition period from _________ to ________ Commission file number 001-40791 2seventy bio, Inc. (Exact name of registrant as specified in its charter) (State or other jurisdiction of incorp ...