mrna-20231231

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 20549

(Mark One)

☒ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the fiscal year ended December 31, 2023

☐ 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: 001-38753

Moderna, Inc.

(Exact Name of Registrant as Specified in Its Charter)

200 Technology SquareCambridge, Massachusetts 02139

(Address of Principal Executive Offices) (Zip Code)

(617) 714-6500

(Registrant’s Telephone Number, Including Area Code)

Securities registered pursuant to Section 12(b) of the Act:

Title of each class Trading Symbol(s) Name of each exchange on which registered

Common stock, par value $0.0001 per share MRNA The Nasdaq Stock Market LLC

Securities registered pursuant to Section 12(g) of the Act: None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes ☑No ☐

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yes ☐No ☑

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ☑No ☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes ☑No ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer”, “accelerated filer”, “smaller reporting company”, and “emerging growth company” in Rule 12b-2 of the Exchange Act.

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report. Yes ☑ No ☐

If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements. ☐

Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant's executive officers during the relevant recovery period pursuant to §240.10D-1(b). ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act). Yes ☐ No ☑

As of June 30, 2023, the aggregate market value of voting and non-voting common equity held by non-affiliates of the registrant was approximately $40.2 billion based on the closing sale price on that date of $121.50. Shares of common stock held by each executive officer and director and by each other person who may be deemed to be an affiliate of the Registrant have been excluded from this computation. The determination of affiliate status for this purpose is not necessarily a conclusive determination for other purposes.

As of February 16, 2024, there were 382,073,208 shares of the registrant’s common stock, par value $0.0001 per share, outstanding.

DOCUMENTS INCORPORATED BY REFERENCE

Portions of the registrant’s Definitive Proxy Statement relating to its 2024 Annual Meeting of Stockholders to be filed hereafter are incorporated by reference into Part III of this Annual Report on Form 10-K where indicated.

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PART I. Page

Item 1. Business 6

Item 1A. Risk Factors 46

Item 1B. Unresolved Staff Comments 79

Item 1C. Cybersecurity 79

Item 2. Properties 80

Item 3. Legal Proceedings 80

Item 4. Mine Safety Disclosures 81

PART II.

Item 6. [Reserved] 83

Item 7A. Quantitative and Qualitative Disclosures about Market Risk 99

Item 8. Financial Statements and Supplementary Data 101

Item 9A. Controls and Procedures 141

Item 9B. Other Information 143

Item 9C. Disclosure Regarding Foreign Jurisdictions that Prevent Inspections 143

PART III.

Item 10. Directors, Executive Officers and Corporate Governance 144

Item 11. Executive Compensation 144

Item 14. Principal Accountant Fees and Services 144

PART IV.

Item 15. Exhibits, Financial Statement Schedules 145

SUMMARY OF THE MATERIAL RISKS ASSOCIATED WITH OUR BUSINESS

Our business is subject to numerous risks and uncertainties that you should be aware of before making an investment decision, including those highlighted in the section entitled “Risk Factors.” These risks include, but are not limited to, the following:

•Evolving dynamics in the market for COVID-19 vaccines are likely to impact our financial results, which are likely to result in lower product revenues in 2024 than we have experienced in recent years;

•We may encounter difficulties producing or shipping our products consistent with our projections or future contractual commitments;

•We have limited sales, distribution and marketing experience and may be unable to effectively establish such capabilities or supplement our capabilities by entering into agreements with third parties;

•The pharmaceutical market is intensely competitive, and we may not compete effectively in the market for existing products, new treatment methods and new technologies;

•We may be unsuccessful or delayed in updating our COVID-19 vaccine to protect against future variants of the SARS-CoV-2 virus, and updated versions of our COVID-19 vaccine may not protect against such variants;

•The commercial success of our products will depend on the degree of market acceptance by physicians, patients, third-party payors and others in the medical community;

•Sales of pharmaceutical products depend on the availability and extent of reimbursement from third-party payors, and we may be adversely impacted by changes to such reimbursement policies or rules;

•Preclinical development is lengthy and uncertain, especially for mRNA medicines, and our preclinical programs or product candidates may be delayed or terminated;

•Clinical development is lengthy and uncertain, and our clinical programs may be delayed or terminated, or may be more costly to conduct than we anticipate;

•If we cannot obtain, or are delayed in obtaining, required regulatory approvals, we will be unable to commercialize, or will be delayed in commercializing, product candidates we may develop;

•Our mRNA products and product candidates are based on novel technologies and are complex and difficult to manufacture. We or our third-party manufacturers may encounter difficulties in manufacturing, product release, shelf life, testing, storage, supply chain management or shipping for any of our products;

•As we grow as a commercial company and our drug development pipeline increases and matures, the increased demand for clinical and commercial supplies from our facilities and third parties may impact our ability to operate. We rely on third-party service providers, all of whom have inherent risks in their operations;

•We are subject to operational risks associated with the physical and digital infrastructure at our manufacturing facilities and those of our external service providers;

•Our individualized neoantigen therapy (INT) product candidates are uniquely manufactured for each patient using a novel, complex manufacturing process and we may encounter difficulties in producing INT;

•We are dependent on single-source suppliers for some of the components and materials used in, and the processes required to develop, our products and product candidates;

•We have entered into, and in the future may enter into, strategic alliances with third parties for the development and commercialization of products and product candidates. If these strategic alliances are not successful, our business could be adversely affected;

•We may seek to establish additional strategic alliances and, if we are unable to establish them on commercially reasonable terms, we may have to alter our development and commercialization plans. Certain of our strategic alliance agreements may restrict our ability to develop certain products;

•We may be unable to obtain and enforce patent protection for our discoveries and the intellectual property rights therein, or protect the confidentiality of our trade secrets;

•Uncertainty over intellectual property in the pharmaceutical and biotechnology industry has been the source of litigation and other disputes, which is inherently costly and unpredictable and can have adverse financial and freedom-to-operate consequences;

•We incurred net losses in 2023 and we are likely to incur losses again in the future; we have a limited history of recognizing revenue from product sales and may be unable to achieve long-term sustainable profitability;

•We may encounter difficulties in managing the development and expansion of our company;

•Our internal computer systems and physical premises, or those of third parties with which we share sensitive data or information, may fail or suffer security breaches, including from cybersecurity incidents, which could materially disrupt our product development programs and manufacturing operations; and

•The price of our common stock has been volatile, which could result in substantial losses for stockholders.

You should consider carefully the risks and uncertainties described below, in the section entitled “Risk Factors” and the other information contained in this Annual Report on Form 10-K, including our consolidated financial statements and the related notes, before you decide whether to purchase our common stock. The risks described above are not the only risks that we face. Additional risks and uncertainties not presently known to us or that we currently deem immaterial may also impair our business operations.

SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This Annual Report on Form 10-K, including the sections entitled “Business,” “Risk Factors” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations,” contains express or implied forward-looking statements within the meaning of the federal securities laws, Section 27A of the Securities Act of 1933, as amended (the Securities Act), and Section 21E of the Securities Exchange Act of 1934, as amended (the Exchange Act). All statements other than statements of historical facts contained in this Annual Report are forward-looking statements. Forward-looking statements in this Annual Report on Form 10-K include, but are not limited to, statements about:

•our expectations regarding the future profitability of our COVID-19 vaccine franchise, as well as our ability to grow and maintain market share;

•our expectations regarding the evolution of the endemic, commercial COVID-19 vaccine market and future demand for COVID-19 vaccines;

•our expectations regarding sales of our COVID-19 vaccine in 2024 and beyond;

•our ability to continue to develop variant-specific versions of our COVID-19 vaccine that are able to effectively combat COVID-19 as the SARS-CoV-2 virus continues to evolve;

•the potential launch, following regulatory approvals, of our respiratory syncytial virus (RSV) vaccine for adults in the first half of 2024, as well as additional respiratory product launches in 2024 and 2025;

•the durability of our individualized neoantigen therapy (INT) candidate, the ability of our INT candidate to address different types of cancer, our Phase 3 clinical trials in adjuvant melanoma and non-small cell lung cancer (NSCLC) and our plans to rapidly expand to additional tumor types;

•our goal to launch up to 15 new products over the next five years;

•our discussions with regulators regarding our first-generation seasonal influenza vaccine candidate (mRNA-1010), and our intent to file for regulatory approval in 2024;

•the potential of our platform to address rare genetic diseases, and our plans to advance propionic acidemia (PA) and methylmalonic acidemia (MMA) programs into pivotal studies in 2024;

•our ability to deliver on the next-generation pipeline and platform, including the commencement of additional clinical trials;

•our ability to successfully contract with third-party suppliers, distributors and manufacturers;

•our ability and the ability of third parties with whom we contract to successfully manufacture, supply and distribute our products, at scale, as well as drug substances, delivery vehicles and product candidates for preclinical and clinical use;

•the scope of protection we are able to establish and maintain for intellectual property rights covering our commercial products, product candidates and technology, including our ability to enter into license agreements, and our expectations regarding pending legal proceedings related to our intellectual property;

•the timing of initiation, progress, completion, results (including interim data) and cost of our clinical trials, preclinical studies and research and development programs, as well as those of our collaborators;

•participant enrollment in our clinical trials, including enrollment demographics and timing;

•potential advantages of mRNA as compared to traditional medicine;

•our ability to obtain and maintain regulatory approval for our products;

•our ability to successfully commercialize our products, if approved, including in light of the size and growth potential of the markets for our products and the degree of market acceptance of our products;

•the pricing and reimbursement of our medicines, if approved;

•the buildout of our manufacturing and commercial operations, including our partnerships with various governments to establish mRNA vaccine manufacturing facilities;

•our financial performance and estimates of our future expenses, revenues and capital requirements;

•the potential benefits of strategic collaboration agreements and our ability to enter into strategic collaborations or other agreements with collaborators with development, regulatory and commercialization expertise;

•legal and regulatory developments in the United States and foreign countries;

•our ability to produce our products or product candidates with advantages in turnaround times or manufacturing cost;

•our ability to attract and retain key scientific, manufacturing, regulatory, commercial and management personnel; and

•developments relating to our competitors and our industry.

In some cases, forward-looking statements can be identified by terminology such as “may,” “should,” “expects,” “intends,” “plans,” “anticipates,” “believes,” “estimates,” “predicts,” “potential,” “continue,” or the negative of these terms or other comparable terminology, although not all forward-looking statements contain these identifying words. Forward-looking statements are based on our management’s belief and assumptions and on information currently available to our management. Although we believe that the expectations reflected in these forward-looking statements are reasonable, these statements relate to future events or our future operational or financial performance, and involve known and unknown risks, uncertainties, and other factors that may cause our actual results, performance, or achievements to be materially different from any future results, performance, or achievements expressed or implied by these forward-looking statements. We may not actually achieve the plans, intentions or expectations disclosed in our forward-looking statements, and you should not place undue reliance on forward-looking statements. Factors that may cause actual results or events to differ materially from current expectations include, among other things, those listed under the section entitled “Risk Factors” and elsewhere in this Annual Report on Form 10-K. If one or more of these risks or uncertainties occur, or if our underlying assumptions prove to be incorrect, actual events or results may vary significantly from those expressed or implied by the forward-looking statements. No forward-looking statement is a guarantee of future performance.

The forward-looking statements in this Annual Report on Form 10-K represent our views as of the date of this Annual Report on Form 10-K. We anticipate that subsequent events and developments will cause our views to change. However, while we may elect to update these forward-looking statements at some point in the future, we have no current intention of doing so except to the extent required by applicable law. You should therefore not rely on these forward-looking statements as representing our views as of any date subsequent to the date of this Annual Report on Form 10-K.

This Annual Report on Form 10-K includes statistical and other industry and market data that we obtained from industry publications and research, surveys, and studies conducted by third parties. Industry publications and third-party research, surveys, and studies generally indicate that their information has been obtained from sources believed to be reliable, although they do not guarantee the accuracy or completeness of such information. We have not independently verified the information contained in such sources.

NOTE REGARDING COMPANY REFERENCES

Unless the context otherwise requires, the terms “Moderna,” the “Company,” “we,” “us” and “our” in this Annual Report on Form 10-K refer to Moderna, Inc. and its consolidated subsidiaries.

TRADEMARKS

This Annual Report on Form 10-K contains references to our trademarks and to trademarks belonging to other entities. Solely for convenience, trademarks and trade names referred to, including logos, artwork and other visual displays, may appear without the ® or TM symbols, but such references are not intended to indicate, in any way, that their respective owners will not assert, to the fullest extent under applicable law, their rights thereto. We do not intend our use or display of other companies’ trade names or trademarks to imply a relationship with, or endorsement or sponsorship of us by, any other companies.

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PART I

Item 1. Business

Moderna is a leader in the creation of the field of messenger RNA (mRNA) medicine. By working at the intersection of science, technology and health for more than a decade, we have developed medicines at unprecedented speed and efficiency, including one of the earliest and most effective COVID-19 vaccines.

Our mRNA platform has enabled the development of therapeutics and vaccines for infectious diseases, immuno-oncology, rare diseases and autoimmune diseases. With a unique culture and a global team driven by the Moderna values and mindsets to responsibly change the future of human health, we strive to deliver the greatest possible impact to people through mRNA medicines.

Our first commercial product, Spikevax (our COVID-19 vaccine), has helped hundreds of millions of people worldwide combat COVID-19. SARS-CoV-2, the virus that causes COVID-19, continues to evolve and in 2023, the COVID-19 vaccine market transitioned to an endemic, seasonal commercial market. To adapt to the evolving market, we significantly resized our manufacturing infrastructure to help position our COVID-19 franchise for future profitability. We achieved 2023 net product sales of $6.7 billion, with $6.1 billion of COVID-19 vaccine sales, and recognition of approximately $0.6 billion of deferred revenue related to our efforts with Gavi, The Vaccine Alliance. In the United States, we achieved 48% market share in the retail market for the 2023 fall season, compared to 37% in the 2022 fall season.

Beyond COVID-19, in 2023, we prepared for the potential 2024 launch of our investigational respiratory syncytial virus (RSV) vaccine for adults, which we expect to further demonstrate the commercial potential of our mRNA platform. In cancer, we reported additional data from our Phase 2b trial evaluating our individualized neoantigen therapy (INT) in combination with Merck’s KEYTRUDA in melanoma patients compared to KEYTRUDA alone. The treatment continued to show significant and clinically meaningful improvement in recurrence-free survival and reduced the risk of recurrence or death by 49%. We believe that these data, with a median follow-up of approximately three years, demonstrate the durability of the therapy, and we have initiated Phase 3 studies in the adjuvant setting in patients with high-risk melanoma and non-small cell lung cancer. We and Merck plan to rapidly expand our clinical trials to additional tumor types.

Having demonstrated clinical benefit in multiple infectious disease areas and skin cancer, as well as potential clinical benefit for several rare genetic diseases, we continue to advance a broad and diverse pipeline and are focused on execution to deliver for patients. Our pipeline includes 45 therapeutic and vaccine programs, nine of which are in late-stage development.

THE mRNA OPPORTUNITY

mRNA, the software of life

mRNA transfers the information stored in our genes to the cellular machinery that makes all the proteins required for life. Our genes are stored as sequences of DNA which contain the instructions to make specific proteins. DNA serves as a hard drive, safely storing these instructions in the cell’s nucleus until they are needed by the cell.

When a cell needs to produce a protein, the instructions to make that protein are copied from the DNA to mRNA, which serves as the template for protein production. Each mRNA molecule contains the instructions to produce a specific protein with a distinct function in the body. mRNA transmits those instructions to cellular machinery, called ribosomes, that make copies of the required protein.

We see mRNA functioning as the “software of life.” Every cell uses mRNA to provide real time instructions to make the proteins necessary to drive all aspects of biology, including in human health and disease. This was codified as the central dogma of molecular biology over 60 years ago, and is exemplified in the schematic below.

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The structure of mRNA

mRNA is a linear polymer comprising four monomers called nucleotides: adenosine (A), guanosine (G), cytosine (C) and uridine (U). Within the region of the molecule that codes for a protein (the coding region), the sequence of these four nucleotides forms a language made up of three-letter words called codons. The first codon, or start codon (AUG), signals where the ribosome should start protein synthesis. To know what protein to make, the ribosome then progresses along the mRNA one codon at a time, appending the appropriate amino acid to the growing protein. To end protein synthesis, three different codons (UAA, UAG, and UGA) serve as stop signals, telling the ribosome where to terminate protein synthesis. In total, there are 64 potential codons, but only 20 amino acids that are used to build proteins; therefore, multiple codons can encode for the same amino acid.

The process of protein production is called translation because the ribosome is reading in one language (a sequence of codons) and outputting in another language (a sequence of amino acids). The coding region is analogous to a sentence in English. Much like a start codon, a capitalized word can indicate the start of a sentence. Codons within the coding region resemble groups of letters representing words. The end of the sentence is signaled by a period in English, or a stop codon for mRNA.

In every cell, hundreds of thousands of mRNAs make hundreds of millions of proteins every day. A typical protein contains 200-600 amino acids; therefore, a typical mRNA coding region ranges from 600-1,800 nucleotides. In addition to the coding region, mRNAs contain four other key features: (1) the 5’ untranslated region (5’-UTR); (2) the 3’ untranslated region (3’-UTR); (3) the 5’ cap; and (4) a 3’ polyadenosine (poly-A) tail. The sequence of nucleotides in the 5’-UTR influences how efficiently the ribosome initiates protein synthesis, whereas the sequence of nucleotides in the 3’-UTR contains information about which cell types should translate that mRNA and how long the mRNA should last. The 5’ cap and 3’ poly-A tail enhance ribosome engagement and protect the mRNA from attack by intracellular enzymes that digest mRNA from its ends.

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The intrinsic advantages of using mRNA as a medicine

mRNA possesses inherent characteristics that we believe position it to have a profound impact on human health:

•mRNA is used by every cell to produce all proteins: mRNA is used to make every type of protein, including secreted, membrane and intracellular proteins, in varying quantities over time, in different locations and in various combinations. Given the universal role of mRNA in protein production, we believe that mRNA medicines could have broad applicability across human disease.

•Making proteins inside one’s own cells mimics human biology: Tailored mRNA can be sent into cells to instruct them to produce specific protein therapeutics or vaccine antigens and provides certain advantages over traditional approaches to medicine, where a protein or chemical is introduced to the body.

•mRNA has a simple and flexible chemical structure: Each mRNA molecule comprises four chemically similar nucleotides to encode proteins madefrom up to 20 chemically different amino acids. To make the full diversity of possible proteins, only simple sequence changes are required in mRNA, instead of starting from scratch for each new vaccine or therapy.

•mRNA has classic pharmacologic features: mRNA possesses many of the attractive pharmacologic features of most modern medicines, including reproducible activity, predictable potency and well-behaved dose dependency; mRNA also provides the ability to adjust dosing based on an individual patient’s needs, including stopping or lowering the dose, to seek to promote safety and tolerability.

Our ability to rapidly develop, manufacture and commercialize vaccines against COVID-19 demonstrates the potential mRNA medicines have to help people and patients in far-reaching ways that could exceed the impact of traditional approaches to medicine.

We believe that the main advantages of mRNA as compared to traditional medicine are:

1.mRNA could create an unprecedented abundance and diversity of medicines. mRNA’s breadth of applicability has the potential to create an extraordinary number of new mRNA medicines that are currently beyond the reach of recombinant protein technology.

2.Advances in the development of our mRNA medicines reduce risks across our portfolio. mRNA medicines share fundamental features that canbe leveraged across our portfolio. We believe that once safety and proof of protein production has been established in one program, the technology and biology risks of related programs that use similar mRNA technologies, delivery technologies and manufacturing processes will decrease significantly.

3.mRNA technology can accelerate discovery and development. The software-like features of mRNA enable rapidin silicodesign and the use ofautomated high-throughput synthesis processes that permit discovery to proceed in parallel rather than sequentially. We believe these mRNA features can also accelerate drug development by allowing the use of shared manufacturing processes and infrastructure.

4.The ability to leverage shared processes and infrastructure can drive significant capital efficiency over time. We believe the manufacturingrequirements of different mRNA medicines are similar and that at commercial scale, a portfolio of mRNA medicines will benefit from shared capital expenditures.

OUR STRATEGY

We believe that the development of mRNA medicines represents a significant breakthrough for patients, our industry and human health globally. Our success in developing one of the earliest and most effective COVID-19 vaccines, at unprecedented speed and efficiency, demonstrates the promise of mRNA medicine. Our COVID-19 vaccine has helped hundreds of millions of people worldwide combat COVID-19. Beyond COVID-19, our platform continues to be highly productive, with 45 programs currently in development, spanning infectious diseases, immuno-oncology, rare diseases and autoimmune diseases.

Across our respiratory vaccines, latent and other vaccines, oncology and rare disease franchises, we are aiming to launch up to 15 new products over the next five years. We have formulated strategic objectives to help enable our near- and long-term goals:

1.Deliver an unrivalled respiratory vaccine franchise. We are developing vaccines against COVID-19, seasonal flu and RSV individually, while pursuing parallel development of combination vaccines. Recognizing that COVID-19 is likely to pose an ongoing health burden, we are making it an important piece of our business with our vaccines against COVID-19 and our investigational combination vaccine against flu and COVID-19. In parallel, we are preparing for the potential 2024 launch of our investigational RSV vaccine for older adults, which is expected to further demonstrate the commercial potential of our mRNA platform. We expect that our anticipated respiratory product launches in 2024 and 2025 will allow us to recognize efficiencies from our growing pipeline.

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2.Advance multiple latent virus and other vaccines. We are developing vaccines against latent and other viruses with unmet or underserved needs, including cytomegalovirus (CMV), Epstein-Barr virus (EBV), herpes simplex virus (HSV), varicella zoster virus (VZV), norovirus, HIV and Lyme disease. We anticipate potential efficacy data from the pivotal Phase 3 study of our CMV vaccine candidate in 2024. CMV is the most common infectious cause of birth defects in the United States and has been designated as a top priority in new vaccine development by the U.S. National Academy of Medicine for more than two decades.

3.Accelerate a large portfolio of late-stage clinical trials in INT to deliver a transformative impact in cancer treatments. In 2023, we reported data from our Phase 2b trial evaluating our INT in combination with Merck’s KEYTRUDA in melanoma patients compared to KEYTRUDA alone, which we believe demonstrates the durability of the therapy. We have launched Phase 3 trials for both adjuvant melanoma and non-small cell lung cancer (NSCLC), and plan to expand the development program to additional tumor types.

4.Accelerate investment in three rare disease programs to pursue potential launches. We have demonstrated the potential for clinical benefit in three different rare genetic diseases (propionic acidemia (PA), methylmalonic acidemia (MMA) and glycogen storage disease type 1a (GSD1a)), and expect to advance our PA and MMA programs into pivotal studies in 2024.

5.Deliver the next-generation pipeline and platform. We have demonstrated clinical benefit in multiple infectious disease vaccines and in skin cancer, as well as potential clinical benefit in three different rare genetic diseases. Based on these clinical successes, we continue to advance a broad and diverse pipeline and are focused on execution to deliver for patients. We plan to continue to invest in our science and our platform to expand mRNA applications and advance new programs into clinical studies.

OUR PLATFORM

Overview of our platform

Our mRNA “platform” refers to our accumulated knowledge and capabilities in basic and applied sciences. Our platform incorporates advances across three key components—mRNA, delivery and the manufacturing process— to advance our medicines. We integrate these components and combine different versions of mRNA delivery and process into each of our medicines.

Our platform: mRNA science advancements

We continue to invest in both basic and applied research, seeking to advance both the state of our technology and the state of the scientific community’s understanding of mRNA. Examples of advances in mRNA science that combine nucleotide chemistry, sequence engineering and targeting elements are described below.

mRNA chemistry: Modified nucleotides to mitigate immune system activation: The innate immune system has evolved to protect cells from foreign RNA, such as viral RNA, by inducing inflammation and suppressing mRNA translation once detected. Many cells surveil their environment through sensors called toll-like-receptors (TLRs). These include types that are activated by the presence of double-stranded RNA (TLR3) or uridine containing RNA fragments (TLR7, TLR8). Additionally, all cells have cytosolic double-stranded RNA, sensors, including retinoic acid inducible gene-I (RIG-I) that are sensitive to foreign RNA inside the cell.

The immune and cellular response to mRNA is complex, context specific, and often linked to the sensing of uridine. To minimize undesired immune responses to our potential mRNA medicines, our platform employs chemically-modified uridine nucleotides to minimize recognition by both immune cell sensors such as TLR3/7/8, and broadly-distributed cytosolic receptors such as RIG-I.

mRNA sequence engineering: Maximizing protein expression: mRNA exists transiently in the cytoplasm, during which time it can be translated into thousands of proteins before eventually being degraded. Our platform applies bioinformatic, biochemical, and biological screening capabilities, most of which have been invented internally that aim to optimize the amount of protein produced per mRNA. We have identified proprietary sequences for the 5’-UTR that have been observed to increase the likelihood that a ribosome bound to the 5’-end of the mRNA transcript will find the desired start codon and reliably initiate translation of the coding region.We additionally design the nucleotide sequence of the coding region to maximize its successful translation into protein.

Targeting elements: Enabling tissue-targeted translation: All nucleated cells in the body are capable of translating mRNA, resulting in pharmacologic activity in any cell in which mRNA is delivered and translated. To minimize or prevent potential off-target effects, our platform employs technologies that regulate mRNA translation in select cell types. Cells often contain short RNA sequences, called microRNAs or miRNAs, that bind to mRNA to regulate protein translation at the mRNA level. Different cell types have different concentrations of specific microRNAs, in effect giving cells a microRNA signature. microRNA binding directly to mRNA effectively silences or reduces mRNA translation and promotes mRNA degradation. We design microRNA binding sites into

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the 3’-UTR of our potential mRNA medicines so that if our mRNA is delivered to cells with such microRNAs, it will be minimally translated and rapidly degraded.

Our platform: Delivery science

Our mRNA can, in specific instances, be delivered by direct injection to a tissue in a simple saline formulation without lipid nanoparticles (LNPs) to locally produce small amounts of pharmacologically active protein. However, the blood and interstitial fluids in humans contain significant RNA degrading enzymes that rapidly degrade any extracellular mRNA and prevent broader distribution without LNPs. Additionally, cell membranes tend to act as a significant barrier to entry of large, negatively-charged molecules such as mRNA. We have therefore invested heavily in delivery science and have developed LNP technologies to enable delivery of larger quantities of mRNA to target tissues.

LNPs are generally composed of four components: an amino lipid, a phospholipid, cholesterol, and a pegylated-lipid (PEG-lipid). Each component, as well as the overall composition, or mix of components, contributes to the properties of each LNP system. LNPs containing mRNA injected into the body rapidly bind proteins that can drive uptake of LNPs into cells. Once internalized in endosomes within cells, the LNPs are designed to escape the endosome and release their mRNA cargo into the cell cytoplasm, where the mRNA can be translated to make a protein and have the desired therapeutic effect. Any mRNA and LNP components that do not escape the endosome are typically delivered to lysosomes where they are degraded by the natural process of cellular digestion. Examples of tools we developed by using our platform include proprietary LNP formulations that address the steps of mRNA delivery, including cell uptake, endosomal escape, and subsequent lipid metabolism, and for avoidance of counterproductive interactions with the immune system.

Chemistry: Novel lipid chemistry to potentially improve safety and tolerability: Our proprietary LNP systems are designed to be highly tolerated and minimize any LNP vehicle-related toxicities with repeat administration in vivo. To overcome limitations of previous LNP formulations, we have engineered amino lipids to avoid the immune system and to be rapidly biodegradable relative to prior lipids.

Composition: Proprietary LNPs enhance delivery efficiency: Our platform includes extensive in-house expertise in medicinal chemistry, which we have applied to design large libraries of novel lipids. Using these libraries in combination with our discovery biology capabilities, we have conducted high throughput screens for desired LNP properties and believe that we have made fundamental discoveries in preclinical studies about the relationships between structural motifs of lipids and LNP performance for protein expression.

Surface properties: Novel LNP design to avoid immune recognition: We have designed our proprietary LNP systems for sustained pharmacology upon repeat dosing by eliminating or altering features that activate the immune system. These are based on insights into the surface properties of LNPs. Upon repeated dosing, surface features on traditional LNPs such as amino lipids, phospholipids, and PEG-lipids, can be recognized by the immune system, leading to rapid clearance from the bloodstream, a decrease in potency upon repeat dosing, and an increase in inflammation.Based on our insights into these mechanisms, we have engineered our LNP systems to reduce or eliminate undesirable surface features. In clinical studies for our systemic therapeutic product candidates that use our novel LNP systems, we have been able to repeat dose with negligible or undetectable loss in potency, liver damage, and immune system activation.

Our platform: Manufacturing process science

We invest significantly in manufacturing process science to impart more potent features to our mRNA and LNPs, and to invent the technological capabilities necessary to manufacture our mRNA medicines at scales ranging from micrograms to kilograms, as well as achieve pharmaceutical properties such as solubility and shelf life. We view developing these goals of manufacturing and pharmaceutical properties as appropriate for each program, based on its stage of development.

mRNA manufacturing process: Improving pharmacology: Our platform creates mRNA using a cell-free approach called in vitro transcription in which an RNA polymerase enzyme binds to and transcribes a DNA template, adding the nucleotides encoded by the DNA to the growing RNA strand. Following transcription, we employ proprietary purification techniques to ensure that our mRNA is free from undesired synthesis components and impurities that could activate the immune system in an indiscriminate manner. Applying our understanding of the basic science underlying each step in the manufacturing process, we have designed proprietary manufacturing processes to impart desirable pharmacologic features, for example increasing potency in a vaccine.

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LNP manufacturing process: Improving pharmacology: Our platform technology includes synthetic processes to produce LNPs. Traditionally LNPs are assembled by dissolving the four molecular components, amino lipid, phospholipid, cholesterol, and PEG-lipid, in ethanol and then mixing this with mRNA in an aqueous buffer. The resulting mixture is then purified to isolate LNPs from impurities. Such impurities include molecular components that have not been incorporated into particles, un-encapsulated mRNA that could activate the immune system, and particles outside of the desired size range.Going beyond optimization of traditional manufacturing processes, we have invested in understanding and measuring the various biochemical and physical interactions during LNP assembly and purification. We have additionally developed state-of-the-art analytical techniques necessary to characterize our LNPs and biological systems to analyze their in vitro and in vivo performance. With these insights, we have identified manufacturing process parameters that drive LNP performance, for example, the potency in a secreted therapeutic setting. These insights have allowed us to make significant improvements in the efficiency of our processing and the potency of our LNPs.

OUR MODALITIES

Our vision for harnessing the power of mRNA through modalities

Within our platform, we invest in science to invent novel ways to deliver mRNA into various cell types. Each novel delivery system is a new application, which we call a “modality.” While the programs within a modality may target diverse diseases, they share similar mRNA characteristics and manufacturing processes to achieve shared product features.

We believe that the high technological correlation within a modality allows us to rapidly accelerate the expansion of programs within that modality based on learnings from the earlier programs, while the lower technology correlation between modalities allows us to compartmentalize the technology risks. Additionally, because programs within a modality pursue diverse diseases, they often have uncorrelated biology risk. Each time we add a modality and a new product candidate to our portfolio, we create a network effect because each incremental program can help us gain additional insight into the other programs in our pipeline.

Although developing a new modality is difficult, time-consuming and expensive, we believe our experience and technology provide us with unique advantages in the development of mRNA medicines. Over the last decade, we have developed a number of modalities, each with one or many product candidates in the clinic. We believe that our ongoing investments in our platform will lead to the identification of additional modalities and expand the utility of our existing modalities and the diversity of our pipeline.

Our current modalities

Our current modalities are described below. More detail regarding our current programs in each modality is provided below under “—Our Pipeline.”

•Infectious disease vaccines: The goal of our infectious disease vaccines is to safely pre-expose the immune system to a small quantity of a protein from a pathogen, called an antigen, so that the immune system is prepared to fight the pathogen if exposed in the future, and prevent infection or disease. Our infectious disease vaccines include those targeting respiratory viruses, latent viruses and enteric viruses, as well as bacterial vaccines and public health vaccines. We believe mRNA vaccines have several advantages, including the ability to mimic many aspects of various infections, the ability to combine antigens for compelling product profiles, the rapid discovery and advancement of programs into the clinic and the capital efficiency and speed from shared manufacturing processes and infrastructure.

•Cancer vaccines and therapeutics: The goal of a cancer therapy is to safely expose the patient’s immune system to tumor-related antigens, known as neoantigens, to enable the immune system to elicit a more effective antitumor response. Our cancer therapies modality is focused on the use of mRNA to express neoantigens found in a particular tumor in order to elicit an immune response via T cells that recognize those neoantigens, and therefore the tumor. These neoantigens can either be unique to a patient or can be related to a driver oncogene found across subsets of patients. Recent breakthroughs in cancer immunotherapy, such as checkpoint inhibitors and chimeric antigen receptor T cell therapies, have demonstrated that powerful antitumor responses can be achieved by activating antigen specific T cells. We believe one approach to improve the efficacy of checkpoint inhibitors is to develop vaccines that increase both the number and antitumor activity of a patient’s T cells that recognize tumor neoantigens. We believe that mRNA technology is an attractive approach for cancer therapies for several reasons, including the ability to deliver multiple personalized neoantigens in a single mRNA molecule, and that mRNA encoding for neoantigens is translated and processed by patients’ endogenous cellular mechanisms for presentation to the immune system.

•Rare disease intracellular therapeutics: The goal of this modality is to provide intracellular proteins, such as intracellular enzymes and organelle-specific proteins, as safe, tolerable, and efficacious therapies. Our mRNA medicines aim to increase levels of intracellular proteins to achieve a therapeutic effect in one or more tissues or cell types and our initial focus is on rare genetic diseases. Intracellular therapeutics are not currently addressable with recombinant proteins, which are typically

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administered systematically and cannot reach inside of the cell. Our potential advantages in these areas include encoding for intracellular and organelle-specific proteins and the production of hard-to-make or complex proteins with native post-translational modifications.

•Intratumoral immuno-oncology: The goal of this modality is to treat or cure cancer by transforming the tumor microenvironment to drive anti-cancer T cell responses against tumors. The outlook for any patients with advanced cancer remains poor, especially in patients with tumors that have little immune system engagement, sometimes termed immunologically “cold.” In conjunction with a checkpoint inhibitor, we aim to activate the immune system against these otherwise immunologically cold tumors. Intratumoral administration allows for localized effect of these therapeutics that could be toxic if administered systemically. We believe our approach to intratumoral immuno-oncology using mRNA medicines could complement checkpoint inhibitors and has several advantages over recombinant protein-based drugs, including production of membrane-associated immune stimulatory proteins, multiplexing of mRNA to access multiple immune stimulatory pathways and creation of engineered mRNA sequences to reduce off-target effects.

•Inhaled pulmonary therapeutics: The goal of this modality is to develop mRNA medicines that can be delivered to the lung as safe, tolerable and efficacious therapies. We are developing nebulized LNP formulations that can transfect airway epithelial cells to deliver mRNA into the lungs of patients in order to express proteins coded in the mRNA. We aim to leverage our technology for pulmonary diseases in patients for whom there are no existing effective therapies. Our potential advantages in these areas include lung-associated production of secreted, membrane-associated or intracellular hard-to-make or complex proteins.

•Systemic secreted and cell surface therapeutics: The goal of this modality is to provide secreted proteins, such as antibodies or enzyme replacement therapies across a wide range of diseases, such as heart failure, infectious diseases, and rare genetic diseases. Our mRNA medicines instruct various cells of the human body to secrete proteins for therapeutic effect. Systemically delivered, secreted and cell surface therapeutics, we believe, would allow us to target areas of biology that cannot be addressed using recombinant proteins. Our potential advantages in this area include encoding for hard-to-make or complex secreted or membrane-associated proteins, multiplexing of mRNA to encode for multiple proteins with complementary activity, native post-translational modifications and sustained production of proteins, which can increase exposure to proteins with short half-lives.

OUR PIPELINE

Over the last decade, we have advanced in parallel a diverse development pipeline that currently consists of 45 therapeutic and vaccine programs, nine of which are in late-stage development. The scope of our pipeline reflects the breadth of biology addressable using mRNA technology. Our selection process for advancing new product candidates reflects both program-specific and portfolio-wide considerations. Program-specific criteria include, among other relevant factors, the severity of the unmet medical need, the biology risk of our chosen target or disease, the feasibility of clinical development, the costs of development and the commercial opportunity. Portfolio-wide considerations include the ability to demonstrate technical success for our platform components within a modality, thereby increasing the probability of success and learnings for subsequent programs in the modality and in some cases in other modalities.

The diversity of proteins made from mRNA within our development pipeline is shown in the figure below.

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Our full pipeline, grouped by modalities, is shown in the figure below:

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INFECTIOUS DISEASE VACCINES MODALITY

We have 31 different infectious disease vaccine programs, of which 30 have entered the clinic. Our infectious disease vaccines modality includes vaccines against respiratory viruses, latent viruses and enteric viruses, as well as bacterial vaccines and public health vaccines.

Infectious disease vaccines: Vaccines against respiratory viruses

COVID-19 vaccines (mRNA-1273/Spikevax®, next-generation mRNA-1283)

Our COVID-19 vaccine is approved or authorized for use in more than 70 countries. COVID-19 is caused by the SARS-CoV-2 virus that was first identified in humans in 2019, driving a global pandemic resulting in millions of deaths. The risk of mortality increases with age and the risk of severe disease and mortality increases for persons with certain pre-existing diseases or comorbid conditions, such as cardiovascular disease, diabetes, chronic lung disease and obesity.

Our COVID-19 vaccine continues to be a key tool in fighting COVID-19 as the SARS-CoV-2 virus evolves. As part of our strategy to combat the virus, we have continued to develop and assess variant-specific versions of our COVID-19 vaccine. In September 2023, we received regulatory approvals in major markets for our updated COVID-19 vaccine (mRNA-1273.815), which targets the XBB.1.5 subvariant of SARS-CoV-2. We developed mRNA-1273.815 in accordance with regulatory guidance, with the goal of broadening vaccine-induced immunity and providing protection against circulating SARS-CoV-2 XBB lineage variants. We have also observed preliminary clinical trial data showing that mRNA-1273.815 generates a robust immune response against other variants of SARS-CoV-2.

The FDA has approved mRNA-1273.815 for individuals ages 12 years and older, and granted Emergency Use Authorization for individuals six months through 11 years of age. mRNA-1273.815 has also been authorized for individuals six months and older in other key markets, including the EU, Canada and Japan.

Forward-looking references to our COVID-19 vaccine in this Annual Report on Form 10-K may include future modifications to mRNA-1273 or other product candidates that are designed to provide protection against variants of the SARS-CoV-2 virus.

In addition to our approved or authorized COVID-19 vaccines, we have advanced other COVID-19 vaccine candidates into the clinic as part of our effort to fight the evolving SARS-CoV-2 virus. Our next-generation COVID-19 vaccine, which is designed to be refrigerator-stable (mRNA-1283), is in a pivotal Phase 3 study, and we anticipate data from the trial in the first half of 2024. Our goal with mRNA-1283 is to facilitate easier distribution and administration by healthcare providers. Further, as SARS-CoV-2 evolves, we continue to perform continuous epidemiological monitoring, genomic surveillance and risk assessments of variants of concern to determine which new variants may have the ability to circumvent immunity provided by currently approved COVID-19 vaccines. For variants that appear to be growing in circulation and have evolved the ability to evade immunity, we proactively develop new product candidates. We have taken several of these candidates to clinical trials, and our monitoring activities allow for expedited delivery of new vaccines in the event that regulatory agencies request specific vaccine composition updates to address public health needs.

COVID-19 Commercial, Manufacturing and Supply Updates

Net product sales of our COVID-19 vaccine were $6.7 billion in 2023, which accounted for all of our product revenues.We anticipate that sales of our COVID-19 vaccine in 2024 will provide a significant portion of our commercial revenues for the coming year. Prior to the third quarter of 2023, we sold our COVID-19 vaccine to the U.S. Government, foreign governments and international organizations. In the third quarter of 2023, we commenced sales of our latest COVID-19 vaccine to the U.S. commercial market, in addition to continuing sales to foreign governments and international organizations.

With COVID-19 entering an endemic phase in 2023, we saw increased seasonality for sales, with greater demand in the fall/winter season in each hemisphere as countries sought to provide vaccinations to their populations.We expect this seasonality to continue in future years in the endemic market. As such, we resized our global manufacturing footprint in 2023 to account for demand in the endemic market. For further information on the sales and manufacturing of our COVID-19 vaccine, see “–Manufacturing” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations” below.

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RSV vaccine (mRNA-1345)

Respiratory syncytial virus (RSV) is one of the most common causes of lower respiratory disease in children under the age of five and in older adults. Populations that are especially vulnerable to developing severe RSV infections include infants, young children, children and adults with chronic medical conditions and older adults. Most children are infected at least once by age two. In the United States, it is estimated that over two million children younger than five receive medical attention and up to 80,000 are hospitalized due to RSV infection annually. RSV also causes a substantial burden of respiratory illness in older adults. RSV infection causes up to 160,000 hospitalizations and up to 10,000 deaths per year in adults aged 65 years or older in the United States.

We are developing an RSV vaccine (mRNA-1345) for children, pregnant women and adults. mRNA-1345 encodes an engineered form of the RSV F protein stabilized in the prefusion conformation and is formulated in our proprietary LNP. In January 2023, we announced that mRNA-1345 had met primary efficacy endpoints in the pivotal Phase 3 trial in older adults, ages 60 and older. mRNA-1345 demonstrated vaccine efficacy (VE) of 83.7% (95.88% CI: 66.1%, 92.2%; p<0.0001) against RSV-associated lower respiratory tract disease (RSV-LRTD) as defined by two or more symptoms. The other primary efficacy endpoint against RSV-LRTD defined by three or more symptoms was also met, with a VE of 82.4% (96.36% CI: 34.8%, 95.3%; p=0.0078). mRNA-1345 was generally well-tolerated with no safety concerns identified. Based on the positive topline data from the pivotal Phase 3 efficacy trial, the FDA granted mRNA-1345 Breakthrough Therapy Designation for the prevention of RSV-LRTD in adults 60 years or older.

We have submitted marketing authorization applications in several major markets for the prevention of RSV-associated lower respiratory tract disease (RSV-LRTD) and acute respiratory disease (ARD) in adults 60 years or older. We expect regulatory approvals beginning in the first half of 2024.

We have additional Phase 3 studies ongoing in adults to explore co-administration with licensed flu or COVID-19 vaccines, revaccination with mRNA-1345 and expansion to adults aged 18 and older who are at high risk for severe RSV disease. In pediatrics, mRNA-1345 is ongoing in Phase 1 and Phase 2 studies, and we are conducting a Phase 2 study in maternal populations.

Seasonal influenza vaccines (mRNA-1010, mRNA-1011, mRNA-1012, mRNA-1020 and mRNA-1030)

The World Health Organization (WHO) estimates that seasonal influenza viruses cause three to five million cases of severe illness and 290,000 to 650,000 deaths each year, resulting in a severe challenge to public health. Currently licensed seasonal influenza vaccines rarely exceed 60% overall effectiveness and can provide low effectiveness during years when the circulating viruses do not match the strains selected for the vaccine antigens.

Our mRNA seasonal influenza vaccine program is taking an iterative approach to development. Our first-generation seasonal influenza vaccine candidate (mRNA-1010) encodes for the hemagglutinin (HA) proteins of the strains recommended by the WHO. We are intending to subsequently improve upon the first-generation candidate through inclusion of additional HA antigens that could provide expanded coverage of co-circulating strains, as well as broadening protection through the addition of another influenza protein, the neuraminidase (NA). We also aim to work with the WHO, regulators and public health authorities to enable strain selection closer to the influenza season to provide a better match to the circulating viruses.

The inclusion of additional HA antigens is being tested in our mRNA-1011/1012 programs, and the addition of NA antigens is being tested in our mRNA-1020/1030 programs. We aim to ultimately combine both approaches into a single next-generation vaccine.

In February 2023, we announced interim results from the P301 study of mRNA-1010. The results indicated that mRNA-1010 achieved higher seroconversion rates for A/H3N2 and A/H1N1, as well as superiority on geometric mean titer ratios for A/H3N2 and non-inferiority on geometric mean titer rations for A/H1N1. Non-inferiority was not met for either endpoints for the influenza B/Victoria- or B/Yamagata-lineage strains. mRNA-1010 showed an acceptable safety and tolerability profile. In April 2023, we announced the P302 study of mRNA-1010 did not accrue sufficient cases at the interim efficacy analysis to declare early success in the Phase 3 Northern Hemisphere efficacy trial. In September 2023, we announced the P303 immunogenicity and safety study of mRNA-1010 met all 8 co-primary endpoints with an updated formulation that was able to generate an improved immune response to influenza B strains. mRNA-1010 also elicited higher titers than the licensed comparator against all strains in this study. An additional study to compare immunogenicity of mRNA-1010 against an enhanced influenza vaccine comparator is currently ongoing. Conversations with regulators regarding filing for approval of mRNA-1010 are currently ongoing and we intend to file for regulatory approval in 2024.

Phase 1/2 studies for our mRNA-1011/1012 and mRNA-1020/1030 programs have been initiated and interim results have been presented at scientific meetings.

Combination vaccines (mRNA-1083, mRNA-1230, mRNA-1045 and mRNA-1365)

We are developing combination vaccine candidates to protect against a range of respiratory diseases.

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mRNA-1083, our next-generation COVID-19 and seasonal influenza combination vaccine, encodes the same antigens as our first-generation seasonal influenza vaccine (mRNA-1010) and our next-generation COVID-19 vaccine (mRNA-1283). In a Phase 1/2 trial, mRNA-1083 showed strong immunogenicity against influenza and COVID-19 compared to licensed standalone vaccines, with an acceptable reactogenicity and safety profile. In October 2023, we initiated a Phase 3 trial in adults 50 years and older. The trial is fully enrolled and data is anticipated in 2024.

We are also conducting Phase 1 studies for mRNA-1230, our COVID-19, seasonal flu and RSV combination vaccine, and mRNA-1045, our seasonal flu and RSV combination vaccine.

Enrollment is ongoing in a Phase 1 trial of mRNA-1365, our RSV and hMPV combination vaccine, in children five to under 24 months of age. In February 2024, the FDA granted Fast Track Designation for mRNA-1365.

Infectious disease vaccines: Vaccines against latent viruses

CMV vaccine (mRNA-1647)

Human cytomegalovirus (CMV) is a common human pathogen and member of the herpes virus family. Congenital CMV results from infected mothers transmitting the virus to their unborn child and it is the leading infectious cause of birth defects in the United States, with approximately 25,000 newborns in the U.S. infected annually. There is currently no available vaccine for CMV and a vaccine that leads to durable immunity in women of child-bearing age would address a critical unmet need in the prevention of congenital CMV infection.

Our CMV vaccine candidate, mRNA-1647, combines six mRNAs in one vaccine, which encode for two proteins located on the surface of CMV: five mRNAs encode the subunits that form the membrane-bound pentamer complex and one mRNA encodes the full-length membrane-bound glycoprotein B (gB). Both pentamer and gB are essential for CMV to infect barrier epithelial surfaces and gain access to the body, which is the first step in CMV infection. mRNA-1647 is designed to produce an immune response against both pentamer and gB for the prevention of CMV infection, which could reduce the risk of birth defects and post-transplant infections.

We are conducting an ongoing Phase 3 study for mRNA-1647, known as CMVictory, to evaluate the safety and efficacy of mRNA-1647 against primary CMV infection in female participants 16 to 40 years of age. The study is fully enrolled, both for the adult and adolescent (ages 16 to <18) cohorts. Timing of the readout will depend upon the number of CMV cases accrued in the study. We anticipate potential efficacy data from the study in 2024.

We are also conducting a Phase 1/2a study of mRNA-1647 in participants 9 to 15 years of age. We enrolled the first participant in November 2022, and the study is evaluating the safety and immunogenicity of mRNA-1647 to inform the selection of a dose level for subsequent development in this age group.

Additionally, in April 2023 we announced that a Phase 2 proof-of-concept study for mRNA-1647 in allogeneic hematopoietic cell transplant (HCT) patients had started enrollment.

EBV vaccine (mRNA-1189 and mRNA-1195)

Epstein-Barr virus (EBV) is a member of the herpesvirus family that is related to CMV and infects approximately 90% of people in the U.S. by adulthood, with primary infection typically occurring during childhood or late adolescence (approximately 50% and 89% seropositivity, respectively). EBV is the major cause of infectious mononucleosis, accounting for over 90% of the approximately one to two million cases in the U.S. each year. Infectious mononucleosis can debilitate patients for weeks to months and, in some cases, can lead to hospitalization due to complications such as splenic rupture. EBV infection is also associated with the development and progression of certain lymphoproliferative disorders, cancers and autoimmune diseases. In particular, EBV infection and infectious mononucleosis are associated with increased risk of developing multiple sclerosis, an autoimmune disease of the central nervous system.

We are developing two EBV vaccine candidates—a vaccine to prevent infectious mononucleosis (mRNA-1189) and a vaccine to prevent the longer-term sequelae of EBV infection (mRNA-1195). Similar to our CMV vaccine (mRNA-1647) product concept, we believe that an effective EBV vaccine must generate an immune response to antigens that are required for viral entry in susceptible cell types. mRNA-1189 is designed to elicit an immune response to EBV envelope glycoproteins, which are required for infection of both epithelial and B cells. mRNA-1189 contains four mRNAs encoding for these proteins encapsulated in our proprietary LNPs. mRNA-1195 encodes for entry glycoproteins and latent antigens and will be investigated in the context of post-transplant lymphoproliferative disorders and multiple sclerosis.

We are conducting Phase 1, randomized, observer-blind, placebo-controlled studies of mRNA-1189 and mRNA-1195. The primary purpose of these studies is to assess the safety, tolerability and immunogenicity of these vaccine candidates.

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HSV vaccine (mRNA-1608)

Herpes simplex viruses (HSV), commonly known as herpes, are categorized into two types: HSV-1 primarily spreads by oral contact and is most commonly associated with cold sores, and HSV-2 spreads through sexual contact and is the major cause of recurrent genital herpes. Both viruses establish life-long latent infections within nearby sensory neurons from which they can reactivate and re-infect the skin. There is a significant burden of disease from HSV genital infections. Diagnosed, symptomatic genital herpes causes a reduction in quality of life, which antivirals (current standard of care) only partially restore. In the United States, approximately 18.6 million adults ages 18 to 49 years are living with HSV-2. Globally, an estimated 492 million persons have HSV-2 infection, representing 13% of the world’s population aged 15 to 49 years. We believe that an HSV vaccine could deliver similar efficacy as suppressive antiviral treatments and could improve compliance and quality of life. We aim to induce a strong antibody response with neutralizing and effector functionality combined with cell-mediated immunity.

We are conducting a Phase 1/2, randomized, observer-blind, controlled, dose-ranging study of mRNA-1608, our HSV vaccine candidate against recurrent HSV-2 disease, in health adults 18 to 55 years of age with recurrent HSV-2 genital herpes. The primary purpose of this study is to assess safety and immunogenicity data, and establish a proof-of-concept of clinical benefit.

VZV vaccine (mRNA-1468)

Herpes zoster, also known as shingles, is caused by the varicella zoster virus (VZV) and occurs in approximately one in three adults in their lifetime and incidence significantly increases at approximately 50 years of age. Protective immunity against VZV wanes as the immune system ages, allowing reactivation of the virus from latently infected neurons, causing painful and itchy lesions. Serious herpes zoster complications include postherpetic neuralgia (10-13% of herpes zoster cases), bacterial coinfections and cranial and peripheral palsies; 1-4% of individuals with herpes zoster cases are hospitalized for complications. Severity of disease and likelihood of complications, including postherpetic neuralgia (PHN) also increases with age. People with immunocompromising conditions, people with autoimmune disease using immunosuppressive therapies, people living with HIV and hematopoietic stem cell (HSCT) and organ transplant recipients have an increased risk of developing herpes zoster. The current standard of care is Shingrix, an FDA-approved vaccine for the prevention of shingles in adults 50 years and older. It is more than 90% effective against herpes zoster in adults aged 50-70 with only a slight reduction in efficacy for adults over age 70.

We are conducting an ongoing Phase 1/2, randomized, observer-blind, active-controlled, dose-ranging study to evaluate the safety, reactogenicity and immunogenicity of mRNA-1468, compared head-to-head with Shingrix, in healthy adults, aged 50 years and older. The first participant was dosed in February 2023 and enrollment of 500 participants was completed in June 2023.

HIV vaccine (mRNA-1644 and mRNA-1574)

HIV is the virus responsible for acquired immunodeficiency syndrome (AIDS), a lifelong, progressive illness with no effective cure. Approximately 38 million people worldwide are currently living with HIV, with 1.2 million in the U.S. Approximately 1.5 million new infections of HIV are acquired worldwide every year and approximately 680,000 people die annually due to complications from HIV/AIDS. The primary routes of transmission are sexual intercourse and IV drug use, putting young adults at the highest risk of infection. From 2000 to 2015, a total of $562.6 billion globally was spent on care, treatment and prevention of HIV, representing a significant economic burden.

We are developing two HIV vaccine candidates—mRNA-1644 and mRNA-1574—both of which are in ongoing Phase 1 clinical trials. In collaboration with the International AIDS Vaccine Initiative (IAVI) and the Bill & Melinda Gates Foundation, mRNA-1644 is testing a novel HIV vaccine strategy in humans as delivered by mRNA to elicit broadly neutralizing HIV-1 antibodies (bnAbs) through sequential vaccination of novel prime and boost antigens that induce specific B-cell responses. In collaboration with IAVI, Scripps, NIH and the HIV Vaccine Trials Network, mRNA-1574 is testing multiple native-like HIV trimer mRNAs in humans to improve our understanding of how to make stable and immunogenic native-HIV trimers.

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Infectious disease vaccines: Vaccines against enteric viruses

Norovirus vaccines (mRNA-1403 and mRNA-1405)

Among enteric viruses, norovirus is a leading cause of diarrheal disease, also referred to as acute gastroenteritis (AGE) globally, resulting in substantial health care burden. Norovirus is estimated to be the causative agent in 18% of all AGE cases worldwide. The highest incidence globally is in young children, and in low-income countries, there are approximately 70,000 deaths annually caused by norovirus in children under 5 years of age. In high-income countries, incidence is also highest among young children, but deaths and other severe outcomes are concentrated primarily among older adults and immunocompromised patients. Norovirus is also associated with large, costly and difficult to control outbreaks in closed and semi-closed settings, such as daycares, cruise ships, long term care facilities and other healthcare settings. The burden of norovirus among older adults is expected to rise along with societal aging and an increased need for institutionalized care. In the U.S., norovirus causes an estimated 20 million infections, 100,000 hospitalizations and 900 deaths per year. Globally, there are approximately 650 million infections annually with approximately 200,000 deaths across all ages.

Norovirus has broad genetic diversity; the virus is classified into 10 genogroups and 49 genotypes, 30 of which are known to infect humans. Vaccine development has been challenging to date for many reasons, including the lack of a robust cell culture system, no reliable immune markers of norovirus protection and the broad and shifting diversity of genotypes. A multivalent vaccine with broad genotype coverage is needed to maximize protection against the genotypes most frequently associated with AGE in young children and older adults.

We are currently developing pentavalent (mRNA-1405) and trivalent (mRNA-1403) vaccine candidates for norovirus. Both candidates are in a Phase 1 study to evaluate safety, reactogenicity and immunogenicity in healthy adult participants 18 to 49 years of age and 60 to 80 years of age. Approximately 660 participants were enrolled in the Phase 1 study, and dosing was completed in December 2023.

Infectious disease vaccines: Bacterial vaccines

Lyme vaccines (mRNA-1975 and mRNA-1982)

Approximately 120,000 Lyme disease cases are reported per year in the U.S. and Europe. With rising atmospheric temperatures, Lyme territory continues to increase in the U.S. Lyme disease burden follows a bimodal age distribution, affecting mainly children under 15 and older adults. Patients can develop rash, fever, headaches, fatigue, joint pain, swelling, stiffness and headaches. Older adults appear more likely to have an unfavorable treatment response and more common neurologic manifestations as compared with younger patients. There are no approved vaccines to prevent Lyme disease in humans currently on the market.

To address Lyme's biological complexity, we are advancing a seven-valent and single-valent approach with two Lyme disease vaccine candidates being developed in parallel. mRNA-1982 is designed to elicit antibodies specific for Borrelia burgdorferi, which causes almost all Lyme disease in the U.S. mRNA-1975 is designed to elicit antibodies specific for the four major Borrelia species causing disease in the U.S. and Europe.

Both the seven-valent (mRNA-1975) and single-valent (mRNA-1982) vaccines are in a Phase 1/2, randomized, observer-blind, placebo-controlled, dose-ranging study to evaluate safety and immunogenicity in healthy participants 18 through 70 years of age. We have completed enrollment of approximately 800 participants in this study. In January 2024, the FDA granted Fast Track Designation to our Lyme disease program.

Infectious disease vaccines: Public health vaccines

Zika vaccine (mRNA-1893)

The Zika virus is a single stranded RNA virus of the Flaviviridae family. Seroepidemiology data suggest that it is endemic to regions of Africa and Asia, where the Aedes mosquito vectors are found. Zika virus is predominantly spread by mosquitos from the Aedes genus, but it can also be transmitted congenitally, sexually and through blood donation. Zika infection is usually asymptomatic or mild in adults, leading to fever, rash and conjunctivitis. However, infection of women during pregnancy can result in devastating microcephaly in newborns. Microcephaly is a birth defect characterized by an abnormally small head and brain, associated with lifelong neurodevelopmental delay, seizures, intellectual disability, balance problems and dwarfism/short stature, resulting in significant disability and requiring lifelong support. In 2007, a Zika infection outbreak progressed across the Pacific islands. An outbreak observed in Brazil in 2015 soon spread across the Americas, which led the WHO to declare Zika a public health emergency of international concern in 2016. During the period, tens of thousands of cases of microcephaly and congenital Zika syndrome were reported in infants. Zika has also been associated with certain neurological sequelae, such as Guillain-Barré syndrome, reported in adults.

Our Zika vaccine candidate, mRNA-1893, encodes for the prME structural protein encapsulated in our proprietary LNP. In partnership with BARDA, we are conducting a Phase 2 study in the United States and Puerto Rico to evaluate mRNA-1893 in approximately 800

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participants. The randomized, placebo-controlled study aims to evaluate the safety, tolerability and reactogenicity of mRNA-1893, as well as evaluate the immunogenicity of two dose levels of mRNA-1893 (one-dose or two-dose schedule) compared to placebo. The study is fully enrolled. We do not anticipate advancing the Zika program into further studies in the absence of further outside funding.

Nipah vaccine (mRNA-1215)

Nipah virus (NiV) is a zoonotic virus transmitted to humans from animals, contaminated food or through direct human-to-human transmission and causes a range of illnesses including fatal encephalitis. Severe respiratory and neurologic complications from NiV have no treatment other than intensive supportive care. The case fatality rate among those infected is estimated at 40-75%. NiV outbreaks cause significant economic burden to impacted regions due to loss of human life and interventions to prevent further spread, such as the slaughter of infected animals. NiV has been identified as the cause of isolated outbreaks in India, Bangladesh, Malaysia and Singapore since 2000 and is included on the WHO R&D Blueprint list of epidemic threats needing urgent R&D action.

In collaboration with the NIH-Vaccine Research Center (VRC), we are conducting an ongoing Phase 1 clinical trial of mRNA-1215, our vaccine candidate against NiV, and testing will be focused on pandemic preparedness. This Phase 1 dose-escalation, open-label clinical trial is the first study of mRNA-1215 in healthy adults to evaluate the safety, tolerability and immunogenicity of a NiV mRNA vaccine candidate. The trial is sponsored and funded by the National Institute of Allergy and Infectious Diseases (NIAID).

Mpox vaccine (mRNA-1769)

Mpox is an infectious viral disease that can occur in humans and some other animals. It is caused by the monkeypox virus, a zoonotic virus in the genus Orthopoxvirus. Transmission of mpox has been associated with direct contact with bodily fluid or sores. Mpox may also be transmitted via respiratory secretion with close face-to-face contact.

The most widely known member of the Orthopoxvirus genus is Variola virus, which causes smallpox. Although smallpox was eradicated in 1977, continued protection from smallpox is of great interest given the lethality of the infection and potential for use as an agent of bioterrorism. Other diseases associated with the Orthopoxvirus genus include cowpox, horsepox and camelpox.

There are two subtypes of the monkeypox virus—Clade I and Clade II. In 2022, an outbreak of the Clade II mpox virus was declared a Public Health Emergency of International Concern by the WHO. The outbreak resulted in approximately 93,000 confirmed cases across 117 countries. More recently, the Clade I monkeypox virus, which is associated with greater mortality, has been reported to be sexual transmitted and there is concern that it may lead to further global outbreaks.

The current standard of care for mpox is Jynneos, which is approved by the FDA for the prevention of mpox and smallpox disease. Our mpox vaccine (mRNA-1769) is designed to express four antigens from the monkeypox virus to provide a range of protection.

We are conducting a randomized, placebo-controlled, dose-ranging, observer-blind Phase 1/2 study to evaluate the safety, tolerability and immunogenicity of mRNA-1769 in healthy participants.

CANCER VACCINES AND THERAPEUTICS MODALITY

Our cancer vaccines and therapeutics modality currently has three development programs, all of which have entered the clinic.

Individualized Neoantigen Therapy (INT) (mRNA-4157)

As tumors grow, they acquire mutations, some of which create new protein segments, or neoantigens, that can be presented on human leukocyte antigen (HLA) molecules in the tumor and recognized as non-self by T cells. While some of these neoantigens could be shared across tumors, the majority are completely unique to an individual patient’s tumor, in addition the presentation of those neoantigens is also dependent on a patient’s specific HLA type.

Our INT, mRNA-4157, uses next generation sequencing and our proprietary algorithm to design an mRNA that encodes up to 34 neoantigens against each individual patient’s tumor mutations with specificity to their HLA type, and is predicted to elicit both class I (CD8) and class II (CD4) responses. The neoantigens are encoded in a single mRNA sequence and formulated in our proprietary LNPs designed for intramuscular injection. INT is manufactured using an automated workflow to enable a rapid turnaround time.

We are developing mRNA-4157 in collaboration with Merck. In September 2022, Merck exercised its option for personalized cancer vaccines, including mRNA-4157, pursuant to the terms of our existing PCV Collaboration and License Agreement with Merck, which was amended and restated in 2018 (PCV Agreement). Pursuant to the PCV Agreement, we and Merck will collaborate on further development and commercialization of mRNA-4157, and we will share costs and any profits and losses worldwide related to mRNA-4157 equally.

In December 2022, we announced that the randomized Phase 2 trial of mRNA-4157 had met its primary endpoint. The open-label Phase 2 study is investigating a 1 mg dose of mRNA-4157 in combination with Merck’s pembrolizumab (KEYTRUDA®), compared

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to pembrolizumab alone, for the adjuvant treatment of high-risk resected melanoma. The study showed that mRNA-4157 in combination with KEYTRUDA reduced the risk of recurrence or death by 44% (HR=0.56 [95% CI, 0.31-1.02]; one-sided p value=0.0266) compared with KEYTRUDA alone. The results are the first demonstration of efficacy for an investigational mRNA cancer treatment in a randomized clinical trial in melanoma. Adverse events observed were consistent with those previously reported in a Phase 1 clinical trial, which showed mRNA-4157 to be well-tolerated at all dose levels.

In February 2023, mRNA-4157 received a Breakthrough Therapy Designation from the FDA, and in April 2023 mRNA-4157 received PRIME Scheme Designation from the EMA.

In December 2023, we announced that at a planned median follow-up of approximately three years, mRNA-4157 in combination with KEYTRUDA showed sustained benefit, reducing the risk of recurrence or death by 49% (HR=0.510 [95% CI, 0.288-0.906]; one-sided nominal p=0.0095) and the risk of distant metastasis or death by 62% (HR=0.384 [95% CI, 0.172-0.858]; one-sided nominal p= 0.0077) compared to KEYTRUDA alone in stage III/IV melanoma patients with high risk of recurrence following complete resection. We and Merck have initiated Phase 3 studies in the adjuvant setting in patients with high-risk melanoma and non-small cell lung cancer (NSCLC), and plan to expand to additional tumor types.

KRAS Vaccine (mRNA-5671)

We are evaluating next steps for our KRAS vaccine program (mRNA-5671), having retained all rights to the program from Merck. Enrollment closed in the Phase 1 study led by Merck in early 2022. KRAS is a frequently mutated oncogene in epithelial cancers, primarily lung, colorectal cancer (CRC) and pancreatic cancers. mRNA-5671 is designed to present neoantigens for the four most prevalent KRAS mutations.

Checkpoint cancer vaccine (mRNA-4359)

We are developing a checkpoint cancer vaccine (mRNA-4359) that express Indoleamine 2,3-dioxygenase (IDO) and programmed death-ligand 1 (PD-L1) antigens. We designed mRNA-4359 with the goal of stimulating effector T cells that target and kill suppressive immune and tumor cells that express target antigens. Our initial indications for mRNA-4359 are advanced or metastatic cutaneous melanoma and NSCLC. Our Phase 1 study of mRNA-4359 is ongoing.

INTRATUMORAL IMMUNO-ONCOLOGY MODALITY

Our intratumoral immuno-oncology modality currently has one development program, which is in the clinic.

OX40L/IL-23/IL-36γ (Triplet) (mRNA-2752)

Despite recent advances in immune-mediated therapies for cancer, the outlook for many patients with advanced cancer is poor. We are developing Triplet (mRNA-2752) to drive anti-cancer T cell responses by transforming cold tumor microenvironments into productive, “hotter” immune landscapes with local intratumoral therapies. mRNA-2752 utilizes the intrinsic advantage of mRNA to multiplex and to produce membrane and secreted proteins with mRNA in a single product candidate. Triplet (mRNA-2752) includes three mRNAs encoding human OX40L, IL-23 and IL-36γ that are encapsulated in our proprietary LNP and administered intratumorally. OX40L is a membrane protein, whereas IL-23 and IL-36γ are secreted cytokines. We believe our approach has the advantage of localized high concentration gradients of IL-23 and IL-36γ compared to recombinant proteins administered systemically or intratumorally. Additionally, the mRNA for OX40L encodes for the wild type membrane protein, which we believe recombinant protein technologies cannot enable.

In December 2023, we completed enrollment in our ongoing Phase 1 dose-escalation study of mRNA-2752 for the treatment of advanced or metastatic solid tumor malignancies or lymphoma (as a single agent or in combination with checkpoint inhibitors).

RARE DISEASE INTRACELLULAR THERAPEUTICS

Our rare disease intracellular therapeutics modality currently has six development programs, three of which are in the clinic.

Propionic acidemia (PA) (mRNA-3927)

PA is a rare, inherited metabolic disorder with significant morbidity and mortality, affecting one in 100,000-150,000 individuals worldwide. PA is caused by pathogenic variants in the propionyl-coenzyme A carboxylase (PCC) α or β subunits (PCCA and PCCB genes, respectively), leading to PCC deficiency and subsequent accumulation of toxic metabolites. PA is characterized by recurrent life-threatening metabolic decompensation events (MDEs) and multisystemic complications. Multisystemic complications include neurological manifestations, cardiomyopathy, arrythmias, growth retardation, recurrent pancreatitis, bone marrow suppression and predisposition to infection. Long-term, insults by toxic metabolites cause complications in various organs, and cognitive outcome is

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negatively correlated with the number of MDEs. Currently, there is no approved therapy for PA that targets the underlying root cause of the disease.

Our PA therapy candidate, mRNA-3927, is a novel, IV-administered, LNP-encapsulated dual mRNA therapy that encodes for PCCA and PCCB subunit proteins to restore functional PCC enzyme activity in the liver. By encoding for intracellular proteins, mRNA therapy has a potential role in preventing and treating acute metabolic decompensations.

The global Phase 1/2 clinical trial for mRNA-3927, the Paramount Study, is ongoing and we have fully enrolled all five dose optimization cohorts, as well as a dose confirmation cohort. The objective of the study is to evaluate the safety and pharmacology of mRNA-3927 in patients 1 year of age and older with PA. The primary endpoints are safety and pharmacokinetics and pharmacodynamics. Secondary endpoints include incidence and severity of adverse events (AEs) and change in plasma biomarkers: methylcitric acid (2-MC) and 3-Hydroxypropionic acid (3-HP). We have received Rare Pediatric Disease Designation, Orphan Drug Designation and Fast Track Designation from the FDA and Orphan Designation from the European Commission for the PA program. Several critical milestones have been reached in the trial. mRNA-3927 has been generally well-tolerated to date with no drug-related serious adverse events, no discontinuations due to safety and only mild-to-moderate infusion related reactions (<10% of doses).Due to the objective and disease-defining nature of MDEs, regulators have provided initial support for MDE as a clinically meaningful, preferred primary clinical endpoint for development. Based on the preliminary data, there was a decrease in the number of MDEs post-mRNA-3927 treatment. We expect to advance mRNA-3927 into a pivotal study in 2024.

Methylmalonic acidemia (MMA) (mRNA-3705)

MMA is a rare, inherited metabolic disorder with significant morbidity and mortality caused by a deficiency in an enzyme called methylmalonyl-CoA mutase (MUT). There are an estimated 500-2,000 people with MMA MUT deficiency in the United States based on estimated birth prevalence (0.3-1.2:100,000 newborns) and mortality rates. Mortality is significant, with mortality rates of 50% for those with complete MUT deficiency (mut 0) (median age of death 2 years) and 40% for MMA patients with partial MUT deficiency (mut -) (median age of death 4.5 years) reported in a large European study. MMA mainly affects the pediatric population and usually presents in the first few days or weeks of life. The occurrence of acute metabolic decompensations is the hallmark of the disorder and decompensations are typically more frequent in the first few years of life. Each decompensation is life-threatening and often requires hospitalization and management at an intensive care unit. Survivors often suffer from numerous complications including chronic renal failure and neurologic complications such as movement disorders, developmental delays, and seizures. Consequently, the health-related quality of life for MMA patients and their families is significantly impaired. There are currently no approved therapies that address the underlying defect for MMA.

Our MMA therapy candidate, mRNA-3705, encodes for a missing or deficient hepatic enzyme. In an ongoing Phase 1/2 study, fifteen participants have been dosed. Thus far, all eligible participants have opted to participate in the Open-Label Extension study. To date, mRNA-3705 has generally been well-tolerated with no discontinuations due to safety or meeting protocol defined dose limiting toxicity criteria. Interim results demonstrated encouraging initial pharmacodynamic data, with dose-dependent reductions in methylmalonic acid in cohorts 2 and 3. Early results suggest potential promising changes in clinical endpoints. We are currently dosing our fifth cohort as we prepare to select an optimal dose for expansion. We expect to advance mRNA-3705 into a pivotal study in 2024.

Glycogen storage disease type 1a (GSD1a) (mRNA-3745)

GSD1a is a rare, inherited metabolic disorder caused by a deficiency in the catalytic activity of the intracellular protein glucose 6-phostphatase (G6Pase). GSD1a patients suffer from severe fasting hypoglycemia, hepatomegaly, nephromegaly, lactic acidemia, hypertriglyceridemia, hyperuricemia, hypercholesterolemia, hepatic steatosis and growth retardation. In addition, hepatocellular adenomas occur in 70% to 80% of GSD1a patients by their third decade of life and carries risk of transformation into hepatocellular carcinomas. Proteinuria has been observed in over half of patients above 25 years of age. GSD1a occurs in approximately 1:100,000 live births in the United States and European Union but is more common in Ashkenazi Jews where the incidence is reported to be 1:20,000 live births. There are an estimated 2,500 people in the United States and over 4,000 people in the European Union with GSD1a. Although strict diet therapy, including frequent feeding with uncooked cornstarch, allows GSD1a patients to live into adulthood by preventing hypoglycemia, the underlying pathological processes remain uncorrected resulting in the development of many long-term complications including liver adenomas and hepatocellular carcinoma.

Our GSD1a therapy candidate, mRNA-3745, consists of an mRNA encoding for modified human G6Pase, and has been granted Orphan Drug Designation by the FDA and the European Medicines Agency (EMA). A Phase 1/2 study to evaluate the safety and pharmacology of mRNA-3745 in GSD1a patients 18 years of age and older is ongoing. We have observed encouraging signs of clinical benefit with mRNA-3745.

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Ornithine transcarbamylase (OTC) deficiency (mRNA-3139)

Ornithine transcarbamylase (OTC) deficiency (OTCD) is an X-linked recessive disorder that is the most common urea cycle disorders (UCDs) in humans. OTCD prevents the breakdown and excretion of ammonia, allowing ammonia to accumulate, rising to toxic levels where it affects the central nervous system. With an incidence of approximately 1:57,000 live births, OTCD accounts for nearly half of all UCDs. OTCD causes high mortality and morbidity, particularly in males.

Our OTCD therapy candidate, mRNA-3139, is in preclinical development. mRNA-3139 is a chronic intravenous, mRNA, enzyme replacement therapy for OTCD, which may act as a bridge to liver transplant or a standalone therapeutic depending on efficacy. mRNA-3139 uses the same LNP as in our GSD1a program.

Phenylketonuria (PKU) (mRNA-3210)

PKU is a rare inherited metabolic disease, affecting approximately 40,000 patients in the United States, France, Germany, Italy, Spain and the UK. Mutations in the phenylalanine hydroxylase (PAH) gene encoding the PAH enzyme result in the inability to metabolize the essential amino acid Phe to Tyr in the liver. There is a high unmet medical need for patients with PKU with early and continuous treatment throughout life being fundamental to prevent the development of irreversible neuropsychiatric outcomes.

Our PKU therapy candidate, mRNA-3210, which is in preclinical development, is an mRNA encoding the PAH enzyme encapsulated in the same LNP as that used in our MMA and PA product candidates, with the potential to address the unmet need in PKU patients.

Crigler-Najjar Syndrome Type 1 (CN-1) (mRNA-3351)

CN-1 is a severe condition caused by the mutations in the UGT1A1 gene. CN-1 is characterized by high levels of a toxic substance called bilirubin in the blood (hyperbilirubinemia). It is caused by mutations in the UGT1A1 gene, which results in an inability to break down bilirubin, a substance made by the liver. Without the UGT1A1 enzyme, bilirubin can build up in the body and lead to jaundice and damage to the brain, muscles and nerves. The symptoms become apparent shortly after birth and can be life-threatening. It is estimated that there are only approximately 70-100 known cases of CN-1 in the world. Affected individuals rely on current standard of care, phototherapy treatments of up to 12 hours a day, throughout life. The only definitive treatment is liver transplant, which is associated with its own set of side effects and risk of death.

Our CN-1 therapy candidate, mRNA-3351, consists of an mRNA encoding human UGT1A1 encapsulated in our proprietary LNPs. It is designed to restore the missing or dysfunctional protein that causes CN-1. We have licensed mRNA-3351 to Institute for Life Changing Medicines (ILCM) with no upfront fees and without any downstream payments. The goal of the collaboration is to make an mRNA therapy for the treatment of CN-1 available at no cost to patients. We are collaborating with the ILCM in developing a preclinical package for Investigational New Drug application and Clinical Trial Application filings. ILCM will be responsible for the clinical development of mRNA-3351.

INHALED PULMONARY THERAPEUTICS

Our inhaled pulmonary therapeutics modality currently has one product candidate.

Cystic Fibrosis (CF) (mRNA-3692/VX-522)

CF is a rare genetic disease, which is progressive from birth and leads to multi-organ damage and early death due to lung dysfunction. It is caused by the mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, which results in the loss of CFTR chloride ion channel function. This decreased function of CFTR at the cell surface leads to thick, sticky mucus in multiple organ systems but most pathologically the lungs. There are approximately 92,000 patients living with cystic fibrosis in the United States, Europe, Australia and Canada, with over 5,000 of these patients not being able to benefit from the approved CFTR modulators.

We are collaborating with Vertex on our CF candidate, mRNA-3692/VX-522, which is designed to treat the underlying cause of CF by enabling cells in the lungs to produce functional CFTR protein for the treatment of the 10% of patients who do not produce any modulator-responsive CFTR protein. This would be our first demonstration of a nebulized mRNA therapy.

Vertex has initiated a Phase 1, single ascending dose clinical trial in CF patients who cannot benefit from CFTR modulators, and the FDA has granted VX-522 Fast Track designation. The trial is active and enrolling patients. Vertex expects to complete the single ascending dose study and to initiate the multiple ascending dose study.

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SYSTEMIC SECRETED AND CELL SURFACE THERAPEUTICS MODALITY

Our systemic secreted and cell surface therapeutics modality currently has two active development programs, of which one has entered the clinic.

Relaxin (mRNA-0184)

Relaxin is a naturally occurring hormone that has been shown to promote vasodilation and angiogenesis, regulate extracellular matrix turnover and suppress arrhythmias post myocardial infarction. Relaxin plays an important role in women in pregnancy, but in addition, studies have pointed to its vasodilatory, antifibrotic, anti-inflammatory and other protective effects on multiple organs. There is a large body of evidence to support relaxin’s clinical potential in several therapeutic areas, with its impact on cardiovascular diseases having been studied in both preclinical and clinical settings. Though prior studies have failed to demonstrate long-term benefit in clinical studies, we believe a novel approach can overcome potential flaws of previous approaches.

We are developing mRNA-0184, which encodes for a relaxin fusion protein, to treat decompensated heart failure. Acute heart failure is defined as the new onset or worsening of symptoms and signs of heart failure. In developed countries, heart failure has become a substantial public health problem, affecting 2% of the adult population and acute heart failure is the most frequent cause of unplanned hospital admission in patients over 65 years of age. mRNA-0184 encodes for the relaxin fusion protein. The mRNA sequence of mRNA-0184 is engineered to increase protein expression and prolong half-life.

In December 2022, we initiated dosing in a Phase 1 trial for mRNA-0184 and the trial is ongoing. Our Phase 1 trial is an adaptive, open-label, single ascending dose to single-blind, placebo-controlled, multiple ascending dose study to evaluate the safety, tolerability, pharmacokinetics, and pharmacodynamics of mRNA-0184 in participants with chronic heart failure.

PD-L1 (mRNA-6981)

PD-L1 is a co-inhibitory receptor that can induce anergy in programmed cell death protein 1 (PD-1)-expressing T cells. We intend to induce expression of PD-L1 on myeloid cells to send a tolerizing signal to immune cells in their environment in order to treat autoimmune diseases.

The PD-L1/PD-1 pathway has a critical function in immune regulation and promotes development and function of regulatory T (Treg) cells. PD-L1 is a transmembrane protein expressed on antigen presenting cells, such as dendritic cells and macrophages, activated T cells, B cells and monocytes, as well as peripheral tissues. Its cognate receptor, PD-1, is a co-inhibitory transmembrane protein expressed on T cells, B cells, natural killer cells and thymocytes. Preclinical mouse models deficient in PD-1 spontaneously develop a variety of autoimmune diseases such as arthritis, myocarditis, lupus-like glomerulonephritis and type 1 diabetes, demonstrating the critical role of the PD-L1/PD-1 interaction in maintaining tolerance to self-antigens. Additionally, treatment of cancer patients with PD-1 or PD-L1 inhibitors sometimes results in immune-related adverse events, including the development of hepatitis, dermatitis and colitis, demonstrating the role of PD-1/PD-L1 in human autoimmune reactions.

We believe our PD-L1 therapy may augment PD-L1 expression on cell types similar to those that endogenously express it, and by reducing immune activation, potentially reduce the clinical manifestations of a variety of autoimmune diseases. Our intent is to use our platform to influence myeloid cells, including dendritic cells, to provide additional co-inhibitory signals by augmenting endogenous expression of PD-L1. We believe that this tolerizing signal to lymphocytes may limit autoreactivity in the context of ongoing autoimmune pathology without severe and global suppression of the immune system. Given that our platform allows us to modify myeloid cells in situ, our approach to the creation of a tolerogenic environment may provide unique benefits in treating autoimmune diseases by seeking to restore immune homeostasis.

After undertaking preclinical development, we determined that the current design of mRNA-6981 does not meet our criteria for advancement to the clinic. PD-L1 continues to be an area of interest, and we are currently evaluating other preclinical mRNA candidates.

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MANUFACTURING

Manufacturing plays a critical role in our value chain and our ability to develop our medicines. Our manufacturing capabilities support every stage of the development of our products, from discovery to commercialization. During the research stage of product development, manufacturing provides mRNA drug substance and drug product for platform research and therapeutic area drug discovery. During early development of our product candidates, we manufacture mRNA and drug product for IND-enabling GLP toxicology studies and initial human clinical studies. For late clinical development, we produce mRNA and drug product for Phase 3 trials. At the commercial stage, we manufacture drug substance and drug product in collaboration with our contract manufacturing organizations (CMOs), both in the United States and internationally.

In 2023, as the COVID-19 vaccine market moved from a pandemic to an endemic market, we significantly resized our manufacturing infrastructure and reshaped our supply capabilities to help position our COVID-19 franchise for future profitability.

Overview of our manufacturing operating model

Our manufacturing activities generally focus on:

•Commercial Production: Our manufacturing capabilities include state-of-the-art technologies for mRNA and drug substance manufacturing, as well as quality control testing to attain a robust and consistent supply that matches target product profiles. Our manufacturing technology is built to scale-up and support production of products for commercial approval. Our platform allows for efficient manufacturing at scale.

•Research and Development Support: The product supply enables platform research and drug discovery in our therapeutic and vaccine areas, in addition to activities related to clinical studies of our product candidates.

We have built a dedicated in-house, multi-building manufacturing campus in Norwood, Massachusetts, the Moderna Technology Center (MTC). The MTC provides supply for our preclinical research, IND-enabling GLP toxicology study supplies, our Phase 1 and Phase 2 pipeline activities, later-stage clinical development activities (e.g., Phase 3 CMV vaccine clinical trials), as well as drug substance commercial production for vaccines. Our vaccine drug substance production for the U.S. market is completed at our MTC campus. The MTC has been designed to allow us to continue to optimize our mRNA products as we explore new pharmaceutical delivery forms in our manufacturing network such as prefilled syringes. The MTC campus has been designed with a high level of automation and state-of-the-art digital integration to handle manufacturing execution, product testing and release, and regulatory filings.

In the second quarter of 2023, we acquired a newly constructed, 140,000 square feet biomanufacturing facility in Marlborough, Massachusetts. The facility is currently undergoing enhancements, including the addition of 60,000 square feet. We expect the facility to be operational in 2025. This new site is strategically intended to support our INT program.

We have also announced agreements with the governments of Australia, Canada and the United Kingdom to establish state-of-the-art mRNA manufacturing facilities in those countries, pursuant to which each government has entered into a multi-year commitment to purchase mRNA products from us, once approved. We expect that these local manufacturing facilities will provide direct access to rapid pandemic response capabilities and our respiratory virus vaccine candidates. We may seek to enter into future agreements with other governments to provide similar manufacturing capabilities in other geographies.

In addition to our internal manufacturing facilities, we also maintain relationships with CMOs in the United States and abroad, providing drug substance and fill-finish capacity for our vaccines. As noted above, during the third quarter of 2023, we resized our manufacturing footprint to reduce our commitments to certain CMOs as a result of lower anticipated demand for COVID-19 vaccines in the endemic market.

Manufacturing technology development

To support our broad pipeline of products, which span multiple therapeutic areas and routes of administration, our platform research and technical development teams closely collaborate to facilitate rapid and seamless clinical translation of scientific breakthroughs. This enables us to develop potential medicines to serve a broad patient population.

Technical development encompasses the design and optimization of robust and consistent manufacturing processes, product characterization, fit-for-purpose formulations and product presentations. For instance, our novel hardware platforms’ automation and robotics, coupled with the flexibility of our in-house digital development systems, allows for thousands of experiments and process parameters across our projects, thus supporting our drug product pharmaceutical readiness. Moreover, our recent technical manufacturing advances have enabled internalization of new key capabilities, including DNA plasmids and small molecules.

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In parallel, we have refined existing processes, resulting in increased manufacturing scale and more robust stability profiles. These improvements allow us significant control over our supply chain, resulting in larger production yields and longer shelf life of our products. Furthermore, formulation development advancements have added new drug product images, including lyophilization, giving us a path from frozen to refrigerated storage conditions.

Our substantial investments in recent years in technical development has enabled the breadth and depth of our pipeline, and laid the foundation to help meet the needs and requirements associated with late-stage development and the commercialization of our products.

Supply of mRNA for All Stages of Product Development and Commercialization

Supply for Research

High-throughput automation and custom engineered equipment allow us to produce and deliver high quality mRNA and formulated constructs in a short period of time: our proprietary platform is capable of producing up to 1,000 lots of mRNA sequences and formulations per month with a turnaround time of a few weeks from sequence to final product. The typical scale of mRNA manufactured by this team is 1-1,000 mg. This has been possible, in part, due to the ability of researchers in the Moderna ecosystem to order constructs through an integrated digital portal that tracks materials end-to-end in less than 45 days. In addition, multiple integrated algorithms that leverage artificial intelligence and machine learning optimize manufacturability, reduce failures and increase quality of mRNA sequences.

Supply for Clinical Development

We have established manufacturing capabilities that support the early development stage of product development in three key areas: GLP Tox, Clinical Studies and INTs. We supply formulated product to conduct IND-enabling GLP toxicology studies. In addition, human clinical studies rely on supply to meet required cGMP standards. This is achieved via internal manufacturing at the MTC campus. Our MTC campus is also suited to enable rapid technology development and scale-up for future needs.

Our manufacturing also produces cGMP INTs. Due to the specialized nature of personalized medicine (i.e., where a batch is specifically designed and manufactured for a single patient), the manufacturing process for INTs has unique requirements. We digitally integrate patient-specific data from sequencing tumor samples to automatically design INTs for patients. We have developed proprietary bioinformatics designed algorithms linked to an automated manufacturing process for rapid production of formulated mRNA, with a typical turnaround time of a few weeks. We have operationalized INT manufacturing at the MTC campus to meet our Phase 1 and 2 pipeline supply needs by using single-use systems with fast “needle-to-needle” turnaround times. Unlike traditional process development, each INT batch is manufactured for a single patient and thus scaled-out (in parallel) with extensive use of automation and robotics to account for the larger number of patients involved in later phases of development and commercialization. We have shown consistent quality in our production of many patient batches, each with unique mRNA sequences. In the second quarter of 2023, we acquired a new manufacturing facility in Marlborough, Massachusetts, which we expect to support our INT program.

Our manufacturing capabilities have allowed us to build our broad pipeline of development programs, including the output required to supply related toxicological and human clinical studies. While the technology that underpins these programs is the same, each program typically requires customization based on target product profiles. These custom features range from varying molecular architecture to different routes of administration, often requiring multivalent products. All programs, with the exception of INT, require that we progressively scale up supply to meet clinical demand requirements across development phases, in addition to the necessary preparation for regulatory approval and commercial production, which demand larger batch sizes. In contrast, the INT program seeks to develop a cancer therapeutic that is designed and manufactured for a specific patient, thus increasing the number of unique batches. As we scale manufacturing output for each program, we plan to continuously improve yield, purity and the pharmaceutical properties of our product candidates.

Supply for Late-Stage Development and Commercialization

As we continue to manufacture our COVID-19 vaccines, our development pipeline continues to advance to later-stage development and towards commercialization. Our platform approach allows us to continue to evolve our manufacturing suites and other capabilities at our manufacturing facilities. mRNA manufacturing is flexible and one plant can manufacture multiple vaccines and therapeutics. Our manufacturing facilities also permit us to manufacture products in parallel. For instance, we can produce drug substance and drug product for our Phase 3 CMV clinical trial while manufacturing COVID-19 drug substance in the same facilities.

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Quality Unit

Quality is core to the way we operate. We seek to ensure quality at Moderna through a combination of a robust Quality Management System (QMS), our quality culture and our people. In accordance with applicable regulations, we have established, documented and implemented a QMS to assure continued compliance with the requirements therein. The QMS facilitates cGMP compliance by implementing practices that identify the various required processes, their application throughout the organization and the sequence of interaction of these processes.

The primary mode of documenting these key practices is through policies, standard operating procedures (SOPs), forms and other quality records, which include an overarching Quality Policy and Quality Manual. We have implemented measurement tools and metrics to monitor, measure, and analyze these practices to support cGMP operations, achieve planned results, and support continuous improvement. We monitor these quality metrics through formal governance processes, including Quality Management Review (QMR), to enable continuous improvement. We have also established an independent Quality Unit that fulfills quality assurance and quality control responsibilities.

Environment, Health, and Safety

We have established a global Environment, Health, and Safety (EHS) organization to foster a safe and healthy work environment with a focus on compliance and sustainability. We achieve this through a combination of training, procedures, digital data collection and reporting tools, and corporate programs that drive towards continuous improvement.

Supply Chain Unit

We have established a global supply chain to enable supply of the raw materials and components used to produce our products, consistent with clinical and preclinical demands. We have worked with our external vendors to characterize critical raw materials and to understand their impact on the quality of drug substance and formulated drug product. We also assess the quality system and performance of our external vendors and work with them to comply with regulatory requirements.

DIGITAL AND AI STRATEGY

Since our founding, we have been a digital-first company, seeking to use the power of digital information to maximize our impact on patients. mRNA is an information molecule, and our company was built on the premise that the natural flow of information in life can be used to develop medicines. Leveraging over a decade of experience developing mRNA medicines, we have built a large library of data that, combined with our platform approach and cloud-native infrastructure, positions us well to scale a digital operating model using artificial intelligence (AI).

Led by our Chief Information Officer, our digital organization partners across all Moderna functions to create an integrated AI ecosystem intended to drive performance and, ultimately, greater patient and business impact. To that end, in 2021, we launched our AI Academy, which offers cross-organization training to all of our employees on topics such as data visualization, machine learning algorithms and AI ethics. Through the AI Academy, our employees learn how to leverage AI in their specific job functions. By embedding AI across our organization, we are able to scale the value of our people and progress toward our goal of becoming a real-time AI company.

AI helps optimize each aspect of our value chain, from drug design to commercial manufacturing and beyond. At the research stage, our digital and AI infrastructure allows our scientists to design novel mRNA constructs, use AI algorithms to optimize them and order them from our high throughput preclinical scale production line. Our capabilities allow us to design mRNA, protein and LNP components with desired properties, such as reduced toxicity or increased stability. At the product development stage, AI helps to improve the efficiency of our clinical trial operations by, for example, forecasting participant enrollment and automating clinical trial data processing.

Our manufacturing processes likewise utilize the power of AI. For example, we leverage a series of fully autonomous, integrated AI algorithms in connection with manufacturing mRNA-4157, our INT candidate. Our proprietary algorithms design the specific therapy for each individual patient and optimize the timely manufacture and delivery of INT to each patient.

At the commercial stage, our digital and commercial organizations came together in 2023 to drive performance and prepare for product launches. Digital and AI are key components of our commercialization strategy, and are vital to our ability to increase our speed to market, enhance our commercial capabilities and continuously improve the quality of our products. We believe that our ability to move with both scale and speed positions us well to pursue our goals related to future product launches.

Further, as generative AI (GenAI) emerged as a transformative technology in 2023, we moved quickly to develop and launch our own internal GenAI product. Recognizing the unique value of Large Language Models (LLMs) to streamline tasks across departments, we launched our internal product in May 2023 after two weeks of development and improved it sequentially thanks to the capabilities of our updated machine learning platform Compute 4.0 for rigorous data management. Approximately 75% of our employees are

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currently active users, embedding the tool into their specific functions for customized support and meaningful improvements to their everyday workflows. This rapid adoption across our company demonstrates the power of our AI-centric culture.

We believe that the integrated AI ecosystem we are building at Moderna will accelerate our mission to deliver the greatest possible impact to people through mRNA medicines.

COMMERCIAL

We are building a differentiated commercial model, with active commercial subsidiaries in key markets across North America, Europe and the Asia-Pacific region. Our growing commercial footprint provides us with local commercial teams in major markets where respiratory vaccines have high utilization rates and sales. To support the build out of our commercial activities in markets around the globe, we have hired talent with extensive pharmaceutical company experience. Our commercial teams also work with third-party distributors and other partners in countries where we do not have a direct presence. Our commercial activities are dependent on regulatory approvals and on agreements that we have made or may make in the future with strategic collaborators.

Before 2023, we sold our COVID-19 vaccine to the U.S. Government, foreign governments and health ministries, Gavi, on behalf of the COVAX Facility, and other international organizations. During the pandemic, these sales were characterized by a relatively limited number of customers that purchased multi-dose vials for distribution through mass vaccination campaigns. As we have transitioned to an endemic market, we have witnessed a shift in demand to single-dose presentations and pre-filled syringes. In 2023, the COVID-19 vaccine market transitioned to an endemic, seasonal commercial market, characterized particularly in the U.S. (our largest market) by a fragmented customer base, less predictability in orders, seasonality of deliveries, significantly lower demand than during the pandemic and the assumption by us of full distribution costs. The private vaccine market is also characterized by market practices regarding rebates, discounts and returns. The COVID-19 vaccine market continues to depend on many evolving factors such as medical need, viral evolution, public health authority recommendations and consumer motivation to vaccinate.

We are also advancing a broader seasonal respiratory vaccine franchise, consisting of single-agent and combination vaccines against RSV, seasonal influenza and COVID-19, which have the highest medical burden among respiratory diseases. We expect regulatory approvals beginning in the first half of 2024 for our RSV vaccine, with multiple respiratory vaccine commercial launches globally over the next several years.

As we advance our portfolio beyond respiratory diseases toward approval, we are also investing in building out our commercial capabilities for other franchises. These franchises include our latent vaccine, rare disease and oncology products, which we expect to launch in the next several years.

We are also working to establish state-of-the-art mRNA manufacturing facilities in Australia, Canada and the United Kingdom, and the government in each of these countries has entered into a multi-year commitment to purchase mRNA products from us, once approved. See “—Manufacturing” above for further detail.

THIRD-PARTY STRATEGIC ALLIANCES

Strategic alliances

We have entered into strategic alliances with a diverse group of collaborators, including pharmaceutical and biotechnology companies, government agencies, academic laboratories, foundations and research institutes with therapeutic area expertise and resources. Through our collaborations, we seek to advance our discovery and development programs, while leveraging our platform and our research and early development capabilities. We also seek to partner with and invest in companies developing other types of therapeutics, such as gene editing and cell-therapy, where we believe we can leverage our core mRNA and LNP capabilities to expand the reach of our technology.

Through certain of our strategic alliances, we share the rewards and risks of developing a new mRNA modality or program, where we may have early research data and desire a strategic collaborator to join us in advancing early development candidates within such modality into the clinic. Representative relationships and associated programs include those with Merck, for our INT programs (mRNA-4157), and Vertex, for our CF program (mRNA-3692).

We view strategic alliances as important drivers for accelerating execution of our goal of rapidly developing mRNA medicines to treat patients across a wide range of medical and disease challenges. To maintain the integrity of our platform, the terms of our strategic collaboration agreements generally provide that either we receive rights to develop and commercialize potential mRNA medicines that we design and manufacture or our strategic collaborators receive rights to develop and commercialize potential mRNA medicines that we design and manufacture, as opposed to granting rights to our strategic collaborators to use our platform to generate new mRNA technologies, and that we generally own intellectual property related to our platform arising from research activities performed under

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the strategic alliance. We plan to continue to identify potential strategic collaborators who can contribute meaningful technology and insights to our programs and allow us to more rapidly expand our impact to broader patient populations.

Below are brief descriptions of certain of our ongoing collaborations. In the fourth quarter of 2023, our Strategic Collaboration and License Agreement with Vertex (the Vertex 2020 Agreement) was concluded and terminated in accordance with the terms of the agreement. The Vertex 2020 Agreement had been aimed at the discovery and development of potential medicines to treat cystic fibrosis (CF) with gene-editing therapies. For additional information on this collaboration, please see Note 5. Collaboration Agreements, to our consolidated financial statements included in this Annual Report on Form 10-K.

Merck—Strategic Alliance for Individualized Neoantigen Therapies

In June 2016, we entered into a Collaboration and License Agreement with Merck for the development and commercialization of personalized mRNA cancer vaccines (also known as INTs), which was subsequently amended and restated in 2018 (the INT Agreement), to develop and commercialize INTs for individual patients using our mRNA vaccine and formulation technology. Under the strategic alliance, we identify genetic mutations present in a particular patient’s tumor cells, synthesize mRNA for these mutations, encapsulate the mRNA in one of our proprietary LNPs and administer to each patient a unique INT designed to specifically activate the patient’s immune system against her or his own cancer cells.

Pursuant to the INT Agreement, we received an upfront payment of $200 million from Merck and we were responsible for designing and researching INTs, providing manufacturing capacity and manufacturing INTs and conducting Phase 1 and Phase 2 clinical trials for INTs, alone and in combination with KEYTRUDA (pembrolizumab), Merck’s anti-PD-1 therapy, all in accordance with an agreed upon development plan and budget.

In September 2022, Merck exercised its option for INTs, including mRNA-4157, pursuant to the terms of the INT Agreement and in October 2022 paid us an option exercise fee of $250 million. Pursuant to the INT Agreement, we and Merck have agreed to collaborate on further development and commercialization of INTs, and we will share costs and any profits or losses worldwide equally.

Vertex—2016 Strategic Alliance in Cystic Fibrosis

In July 2016, we entered into a Strategic Collaboration and License Agreement (Vertex Agreement) with Vertex Pharmaceuticals Incorporated, and Vertex Pharmaceuticals (Europe) Limited (together, Vertex). The Vertex Agreement is aimed at the discovery and development of potential mRNA medicines for the treatment of CF by enabling cells in the lungs of people with CF to produce functional cystic fibrosis transmembrane conductance regulator (CFTR) proteins.

Other Collaborations

In September 2020, we entered into a collaboration with Chiesi Farmaceutici S.p.A. (Chiesi), an international research-focused healthcare group, aimed at the discovery and development of mRNA medicines for the treatment of pulmonary arterial hypertension (PAH), a rare disease characterized by high blood pressure in the arteries of the lungs. Under the terms of the Chiesi agreement, we will lead discovery efforts, and Chiesi will lead development and worldwide commercialization activities and will fund all expenses related to the collaboration.

We have entered into additional collaborations where we have agreed to provide funding in areas where we believe we can leverage our mRNA technology. These collaborations include those with:

•Carisma Therapeutics, to discover, develop and commercialize in vivo engineered chimeric antigen receptor monocyte (CAR-M) therapeutics for the treatment of cancer, including solid tumors.

•CytomX Therapeutics, to create investigational mRNA-based conditionally activated therapies utilizing our mRNA technologies and CytomX’s Probody platform.

•Generation Bio Co., to combine our biological and technical expertise with core technologies of Generation Bio's non-viral genetic platform.

•Immatics N.V., to pioneer novel and transformative therapies for cancer patients with high unmet medical need.

•Life Edit Therapeutics, to discover and develop in vivo mRNA gene editing therapies.

•Metagenomi, focused on discovering and advancing new gene editing systems for in vivo human therapeutic applications.

We have made equity investments in Carisma, Generation Bio and Metagenomi pursuant to those collaborations.

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Strategic alliances with government organizations and foundations

Defense Advanced Research Projects Agency (DARPA)

In September 2020, we entered into an agreement with DARPA to fund development of a mobile manufacturing prototype leveraging our existing manufacturing technology that is capable of rapidly producing vaccines and therapeutics.

Biomedical Advanced Research and Development Authority (BARDA)

In September 2016, we received an award of up to approximately $126 million, subsequently adjusted to $117 million in 2021, from BARDA, a component of the Office of the Assistant Secretary for Preparedness and Response (ASPR), within the U.S. Department of Health and Human Services (HHS), to help fund our Zika vaccine program. In September 2022, the performance period of the grant expired, and BARDA was released of the obligation to fund the remaining $36 million of the award.

In April 2020, we entered into an agreement with BARDA for an award of up to $483 million to accelerate development of mRNA-1273, our original COVID-19 vaccine. The agreement has been subsequently amended to provide for additional commitments to support various late-stage clinical development efforts of mRNA-1273, including a 30,000 participant Phase 3 study,pediatric clinical trials, adolescent clinical trials and pharmacovigilance studies. The maximum award from BARDA, inclusive of all amendments, was approximately $1.8 billion. All contract options have been exercised. As of December 31, 2023, the remaining available funding, net of revenue earned was $97 million.

Institute for Life Changing Medicines (ILCM)

In September 2021, we entered into a collaboration agreement with the ILCM to develop a new mRNA therapeutic (mRNA-3351) for type 1 Crigler-Najjar syndrome (CN-1). Under the terms of the agreement, we agreed to license mRNA-3351 to ILCM with no upfront fees, and without any downstream payments. ILCM will be responsible for the clinical development of mRNA-3351.

The Bill & Melinda Gates Foundation

In January 2016, we entered a global health project framework agreement with the Bill & Melinda Gates Foundation to advance mRNA development projects for various infectious diseases. The Bill & Melinda Gates Foundation has committed up to $20 million in grant funding to support our initial project related to the evaluation of antibody combinations in a preclinical setting as well as the conduct of a first-in-human Phase 1 clinical trial of a potential mRNA medicine to help prevent HIV infections. Follow-on projects, which could bring total potential funding under the framework agreement up to $100 million (including the HIV antibody project) to support the development of additional mRNA projects for various infectious diseases, can be proposed and approved until the sixth anniversary of the framework agreement, subject to the terms of the framework agreement, including our obligation to grant to the Bill & Melinda Gates Foundation certain non-exclusive licenses.

INTELLECTUAL PROPERTY

We rely on a combination of intellectual property laws, including patent, trademark, copyright and trade secret, as well as confidentiality and license agreements, to protect our intellectual property and proprietary rights.

Protecting our platform, modality and program investments: Building an expansive, multi-layered IP estate

We have built a substantial IP estate that includes numerous patents and patent applications related to the development and commercialization of mRNA vaccine and therapeutic development candidates, including related platform technologies. Our platform IP protects advances in mRNA design and engineering, proprietary LNP components, delivery systems, processes for the manufacture and purification of drug substances and products and analytical methods. A significant portion of our platform IP estate further provides multi-layered protection for our modalities and programs.

With respect to our IP estate, our solely-owned patent portfolio consists of more than 230 issued or allowed U.S. patents or patent applications and more than 170 granted or allowed patents in jurisdictions outside of the U.S. (including granted European patents that have been validated in numerous European countries) covering certain of our proprietary platform technology, inventions and improvements, and covering key aspects of our clinical and most advanced development candidates. We have over 400 additional pending patent applications that, in many cases, are counterparts to the foregoing U.S. and foreign patents.

Most of the patents and applications (if issued) in our portfolio will not expire until 2033 at the earliest. Any patent that may issue from our most recently filed patent applications is projected to expire between 2042 and 2043, at the earliest. We file additional U.S. and foreign patent applications as necessary to protect our evolving intellectual property positions.

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We also rely on trademarks, copyright, trade secrets and know-how relating to our proprietary technology and programs, continuing innovation, and in-licensing opportunities to develop, strengthen and maintain our proprietary position in the field of mRNA therapeutic and vaccine technologies. We take additional steps, such as entering into confidentiality and license agreements, to protect our intellectually property and proprietary rights. We additionally plan to rely on data exclusivity, market exclusivity and patent term extensions when and where available, and plan to seek and rely on regulatory protection afforded through orphan drug designations. We also possess substantial proprietary know-how associated with related manufacturing processes and expertise.

IP protecting our platform

We have a broad IP estate covering key aspects of our platform. This estate provides multiple layers of protection covering the making and use of the mRNA drug substance and delivery technologies.

With respect to our platform, we have a portfolio that includes U.S. and foreign patents or patent applications covering platform innovations that are related to the design, manufacturing and formulating of mRNA medicines. For example, these patents and patent applications include claims directed to:

•mRNA chemistry imparting improved properties for vaccine and therapeutic uses;

•methods for mRNA sequence optimization to enhance the levels and fidelity of proteins expressed from our mRNA medicines;

•methods for identifying epitopes having superior suitability in cancer vaccine contexts;

•engineering elements tailored to enhance stability and the in vivo performance of mRNA medicines;

•LNP delivery systems, including novel lipid components designed for optimal delivery and expression of both therapeutic and vaccine nucleic acids, in particular, prophylactic infectious disease and cancer vaccine nucleic acids, intratumoral immuno-oncology therapeutics, local regenerative therapeutics, systemic therapeutics, and inhaled pulmonary therapeutics; and

•innovative processes for the manufacture and analysis of mRNA drug substance and formulated drug product.

IP protection

Our IP estate provides protection for the multiple programs both at the product-specific level and at various broader levels. For example, we have patent coverage for LNP-encapsulated mRNAs having specific chemical modification suited for vaccine and therapeutic mRNA use. Our estate also includes IP covering certain LNP-encapsulated mRNAs coding for infectious disease antigens for use in preventing or treating infectious diseases, including those caused by respiratory and latent viruses, as well as bacterial, viral and parasitic diseases known to threaten public health. Our mRNA chemistry, formulation and manufacturing patent applications and related know-how, along with trade secrets, may also provide us with additional IP protection relating to our development candidates.

Respiratory vaccines

For our respiratory vaccines programs, we have pursued patent protection featuring composition of matter and method of use claims. Where we may pursue patent protection may vary based on the unique geographic prevalence of various infectious diseases.

We have filed several patent applications covering our betacoronavirus vaccine program. We are pursuing patent protection for both our existing and next generation betacoronavirus vaccines. A non-exhaustive list of granted patents covering our COVID-19 vaccine can be found in the following table.

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Patent Number Country/Region* Patent Type Expiration Date**

10,898,574 United States Composition of Matter and Method of Use April 2, 2032

3 590 949 Europe Composition of Matter and Method of Use October 3, 2031

* Selected granted patents in the U.S. and Europe only. Additional granted and pending patents in the U.S., Europe and other countries may be available.

** Expiration dates listed here include any granted or anticipated patent term adjustment (PTA), but not any patent term extension (PTE) or supplementary protection certificates (SPC).

RSV

We have filed multiple patent families directed to RSV vaccines, including a U.S. patent that issued on October 11, 2022.Our RSV patent portfolio includes multiple families of differing patent breadth. At least four U.S. and European patent applications are pending.

Influenza

We have multiple patent families spanning different levels of breadth, design and antigen valency pending in the U.S., Europe and around the world, including several granted patents.

hMPV

Human metapneumovirus (hMPV) is a single-stranded RNA virus that is used in a combination program. We have patent applications covering our hMPV vaccine pending in the U.S. and Europe, with a granted patent in the U.S.

Latent vaccines

We have vaccine programs and patent applications directed to both the acute and latent forms of diseases caused by various viruses, including CMV, EBV, HSV, VZV and HIV, using both preventative vaccines targeting the acute phase and therapeutic vaccines for treating the latent diseases in those who do become infected.

CMV

The patent coverage for our human CMV vaccine candidate is extensive and is based on a vaccine with six mRNAs encoding a pentamer surface glycoprotein complex and the gB surface glycoprotein. Both pentamer and gB facilitate entry of the virus into different cell types and therefore immune responses targeting these proteins can block virus entry, spread and reactivation. The current patent portfolio contains both compositions of matter and methods of treating subjects using the vaccine. In the U.S., our CMV vaccine is covered by multiple issued U.S. patents of differing breadth. Each family has counterparts consisting of pending applications and issued patents in non-U.S. jurisdictions, including Europe and Japan. A separate family of CMV patents, which includes mRNA-1647 plus mRNA-1443 for use in CMV vaccines for transplant indications, is also yielding patents and applications in foreign jurisdictions are pending.

EBV, HSV and VZV

Similar to CMV, we have multiple patent families pending for each of EBV, HSV and VZV, covering both prophylactic and therapeutic indications. These patent families have also been filed in Europe and Japan.

Public health vaccines

We maintain a multi-program effort at developing vaccines for potential future pandemics and for use in parts of the world with less well-established health care systems. This group of programs include infectious diseases such as flaviviruses such as Zika and dengue

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viruses, HIV, Nipah virus, and the Mpox virus. In addition, programs are ongoing in many bacterial diseases. Specific patent families are being filed on most potential public health programs where possible, but in some scenarios, platform patents may be used to augment patent protection for public health target vaccines.

Individualized neoantigen therapy (INT)

Composition of matter and method claims are being pursued to protect programs within our cancer vaccines modality. Proprietary methods around the making and therapeutic use of our INTs and resulting vaccine compositions are described and claimed in seven pending U.S. patent applications, six pending European patent applications, five pending patent applications in Japan, three pending patent applications and one granted patent in China, and several pending patent applications in New Zealand, South Africa, Asian and South American countries, as well as one PCT application. These applications also relate to various vaccine design formats, in particular, polyepitopic vaccine formats, and methods of treating cancer with such INTs. We also possess substantial know-how and trade secrets relating to the development and commercialization of our cancer vaccine programs, including related manufacturing process and technology.

Likewise, our KRAS antigen cancer vaccine and methods of treating cancer featuring such vaccines are covered in an issued U.S. patent, which includes claims to LNP-encapsulated mRNA encoding mutant KRAS antigens.

Intratumoral immuno-oncology

We have filed numerous patent applications featuring claims to mRNAs encoding immune-stimulatory proteins and methods of treating cancer using such compositions.

Our immuno-oncology programs are designed to be administered intratumorally to alter the tumor microenvironment in favor of mounting an immune response against tumors. Our mRNA program that includes mRNAs that encode OX40L, IL-23 and IL-36γ are covered by two granted European patents, by more than 10 issued U.S. patents, by several pending U.S. and European patent applications and by several pending patent applications in other foreign jurisdictions. These applications feature claims to the mRNA therapeutics as compositions of matter, formulations that include such mRNAs and methods of reducing tumors and treating cancer using these development candidates.

Rare diseases

We have programs featuring expression of therapeutic proteins, e.g., intracellular enzymes for the treatment of rare diseases. For our rare disease programs, we generally pursue patent protection featuring composition of matter and method of use claims, for example, pharmaceutical composition and method of treatment claims. Our most advanced rare disease development candidate is for PA. For this candidate, we have patent applications pending in the United States, Europe, and Japan which cover mRNA encoding the alpha and beta subunits of the enzyme propionyl-CoA carboxylase (PCCA and PCCB, respectively), for the treatment of PA.

For MMA, we have patent applications issued and pending in the U.S. and foreign applications filed in Japan and Europe.

For our PKU development candidate, we have a pending PCT and pending patent applications in the U.S., Europe and Japan covering mRNA encoding phenylalanine hydroxylase (PAH) for the treatment of PKU.

For our Glycogen Storage Disorder, Type 1a (GSD1a) development candidate, we have filed several patent families, including pending U.S. and European patent applications, as well as applications pending in China and Japan covering mRNA encoding glucose 6-phosphatase (G6Pase) for the treatment of this disorder.

For our Crigler-Najjar Syndrome Type 1 (CN-1) development candidate, we have patent applications pending in the U.S., Europe and Japan.

Our ornithine transcarbamylase deficiency (OTC) development candidate is covered by a pending PCT application.

Any U.S. and foreign patents that may issue from these patent families would be expected to expire in 2036 for the earliest of the MMA patents and 2038 to 2042 for the remaining MMA, PA, PKU, GSD1a and CN-1 patents, excluding any patent term adjustments, any patent term extensions and any terminal disclaimers.

As further described below, we have filed or intend to file patent applications on these and other aspects of our technology and development candidates, and as we continue the development of our intended products, we plan to identify additional means of obtaining patent protection that would potentially enhance commercial success, including protection for additional methods of use, formulation, or manufacture.

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Systemic secreted and cell-surface therapeutics

Our systemic secreted and cell-surface therapeutics modality features programs directed to expression of secreted or cell-surface proteins including antibodies, circulating immune modulation factors, secreted enzymes and transmembrane proteins.

Our Relaxin development candidate is covered by several patent families, including granted patents in Japan, China and the U.S., and by additional applications in the U.S. and additional foreign jurisdictions and a pending PCT application.

Our PD-L1 development candidate is covered in pending patent applications filed in the U.S., Japan and Europe.

Inhaled pulmonary therapeutics

Our inhaled pulmonary therapeutics modality currently has one development candidate directed to expression of therapeutic protein in the lungs. This Cystic Fibrosis (CF) development candidate is covered by pending U.S., European and PCT patent applications.

Gene editing

Our gene editing program currently has one filed patent family that includes issued patents in the U.S., Europe and Japan, and also pending applications in these jurisdictions. We plan to file patent applications on development candidates and other aspects of gene editing technology as we continue to innovate both internally and through strategic collaborations.

Trademarks

Our trademark portfolio currently contains at least 1,000 trademark registrations, including at least 22 registrations in the United States and the remaining in Canada, the European Union, the United Kingdom, Israel, China, Japan, Australia, and elsewhere. In addition, we have at least 600 pending trademark applications in more than 95 jurisdictions, including in the aforementioned locations and additional countries throughout Africa, Asia, and South America.

In-licensed intellectual property

While we develop and manufacture our potential mRNA medicines using our internally created mRNA technology platform, we also seek out and evaluate third party technologies and IP that may be complementary to our platform.

Patent sublicense agreements with Cellscript and mRNA RiboTherapeutics

The Trustees of the University of Pennsylvania owns several issued U.S. patents, granted European patents and pending U.S. patent applications directed, in part, to nucleoside-modified mRNAs and their uses (the Penn Modified mRNA Patents). mRNA RiboTherapeutics, Inc. (MRT) obtained an exclusive license to the Penn Modified mRNA Patents and granted its affiliate, Cellscript, LLC (Cellscript), a sublicense to the Penn Modified mRNA Patents in certain fields of use.

In June 2017, we entered into two sublicense agreements, one with Cellscript, and one with MRT, which agreements we collectively refer to as the Cellscript-MRT Agreements. Together, the Cellscript-MRT Agreements grant us a worldwide, sublicensable sublicense to the Penn Modified mRNA Patents to research, develop, make, and commercialize products covered by the Penn Modified mRNA Patents (licensed products), for all in vivo uses in humans and animals, including therapeutic, prophylactic, and diagnostic applications. The Cellscript-MRT Agreements are non-exclusive, although Cellscript and MRT are subject to certain time restrictions on granting additional sublicenses for in vivo uses in humans under the Penn Modified mRNA Patents. The Cellscript-MRT Agreements require us to pay royalties based on annual net sales of licensed products at rates in the low single digits for therapeutic, prophylactic, and diagnostic uses, and royalties based on annual net sales of licensed products sold for research uses at rates in the mid-single digits, subject to certain reductions, with an aggregate minimum floor.

The Cellscript-MRT Agreements will terminate upon the expiration or abandonment of the last to expire or become abandoned of the Penn Modified mRNA Patents. Cellscript or MRT, as applicable, may terminate its respective Cellscript-MRT Agreement if we fail to make required payments or otherwise materially breach the applicable agreement, subject to specified notice and cure provisions. Cellscript or MRT, as applicable, may also terminate the applicable Cellscript-MRT Agreement upon written notice in the event of our bankruptcy or insolvency or if we challenge the validity or enforceability of the Penn Modified mRNA Patents. We have the right to terminate each Cellscript-MRT Agreement at will upon 60 days’ prior notice to Cellscript or MRT, as applicable, provided that we cease all development and commercialization of licensed products upon such termination. If rights to MRT or Cellscript under the Penn Modified mRNA Patents are terminated (e.g., due to bankruptcy of MRT or Cellscript), the terminated party will assign its interest in the respective Cellscript-MRT Agreement to the licensor from which it received rights under the Penn Modified mRNA Patents and our rights will continue under the new licensor.

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Patent license agreement with NIAID

In December 2022, we entered into a non-exclusive patent license agreement with the National Institute of Allergy and Infectious Diseases (NIAID), an Institute or Center of the National Institutes of Health (NIH) to license certain patent rights concerning stabilizing prefusion coronavirus spike proteins and the resulting stabilized proteins for use in COVID-19 vaccine products. Pursuant to the agreement, we have agreed to pay low single-digit royalties on future net sales, a minimum annual royalty payment and certain contingent development, regulatory and commercial milestone payments on a licensed product-by-licensed product basis.

Formulation technology in-licenses

Our development candidates use internally developed formulation technology that we own. We do, however, have rights to use and exploit multiple issued and pending patents covering formulation technologies under licenses from other entities. If in the future we elect to use or to grant our strategic collaborators sublicenses to use these in-licensed formulation technologies, we or our strategic collaborators may be liable for milestone and royalty payment obligations arising from such use. We consider the commercial terms of these licenses and their provisions regarding diligence, insurance, indemnification and other similar matters, to be reasonable and customary for our industry.

HUMAN CAPITAL

We had approximately 5,600 full-time employees in 19 countries around the world as of December 31, 2023. We operate in a highly competitive environment for talent, particularly as we seek to attract and retain talent with experience in the biotechnology and pharmaceutical sectors. Our workforce is highly educated, and as of December 31, 2023, 41% of our employees hold Ph.D., Doctorate, M.D., J.D. or Master’s degrees. Among our employees, as of December 31, 2023, 49% are female. Among our leadership (which we define as employees at the vice president level and above), as of December 31, 2023, approximately 39% are female. 45% of our U.S. employees identify as racially or ethnically diverse as of December 31, 2023, an increase from the prior year. In 2023, for the second year in a row, an outside statistical pay equity analysis confirmed zero statistically significant differences in pay across gender globally and across gender, race and ethnicity in the United States.

Our focus on belonging, inclusion and diversity

We are committed to building a culture of inclusion and belonging for all. In 2023, we continued to act on our commitment to belonging, inclusion and diversity by, among other things:

•continuing our monitoring and reporting of company-wide gender and ethnicity data;

•including a belonging, inclusion and diversity focus in every employee engagement survey;

•continuing to invest in our Employee Resource Groups, which are voluntary, employee-led groups that harness the power of belonging in service to our people, our company and the community at large, including by introducing mCARE, a group dedicated to supporting and empowering our employees who are caregivers and parents;

MRNA US Equity

MRNA · 10-K · period ended 2023-12-31

Item 1. Business

MRNA US Equity☆

MRNA · 10-K · period ended 2023-12-31

Item 1. Business

MRNA US Equity