Moderna Highlights Advances in Platform Science and Innovative Vaccine Research at Fourth Annual Science Day

• Research includes innovations in lipid nanoparticle technology for mRNA delivery into hematopoietic stem and progenitor cells
• Intracellular event-guided rational design of lipid nanoparticle
• Assessment and prediction of SARS-CoV-2 variants for selection of COVID-19 booster vaccines

Moderna, Inc., (Nasdaq: MRNA) a biotechnology company pioneering messenger RNA (mRNA) therapeutics and vaccines, today announced new research being highlighted as part of the Company’s fourth annual Science Day. Moderna’s Science Day is designed to provide insight into the continued diverse efforts underway at Moderna to better understand how to use mRNA as medicines and vaccines and underscores the Company’s continued commitment to basic science and innovation.

“Science Day gives us an opportunity to provide insights into the advancements in our platform science and our further understanding of how to use mRNA as both a vaccine and a medicine. Our investments in basic science continue to result in major steps forward in our platform’s capabilities, and these have allowed us to open new therapeutic areas and new scientific directions,” said Stephen Hoge, M.D., President of Moderna. “Our investments in platform research along with our digital backbone and manufacturing plants have enabled us to create first-in-class mRNA medicines and vaccines. Today, we're excited to highlight our work to identify and address SARS-CoV-2 variants of concern, optimize our proprietary lipid nanoparticle (LNP) technology, and deliver mRNA to hematopoietic stem cells.”

Moderna currently has 24 mRNA development programs in its portfolio with 14 having entered clinical studies. The Company’s updated pipeline can be found at www.modernatx.com/pipeline. Moderna and collaborators have published more than 65 peer-reviewed papers.

At this year’s Science Day, Moderna will present new platform science and preclinical research, including:

mRNA Delivery to ​Hematopoietic Stem and Progenitor Cells​ (HSPC)

Of the nearly 30 trillion cells in the body, approximately 90% are of hematopoietic origin. Hematopoietic lineages originating in the bone marrow are intimately involved in maintaining homeostasis and human health. Nonetheless, there are hundreds of hematologic or immune-related disorders caused or exacerbated by cells of the hematopoietic lineage. In a disease setting, cells of hematopoietic origin interact with host tissues to drive chronic inflammatory and immune disorders. Because some hematopoietic stem and progenitor cells (HSPC) have self-renewal and pluripotent properties, targeting HSPC has the potential to modulate underlying chronic inflammation and immune-related disorders.

Advances in lipid nanoparticle (LNP) technology has allowed for delivery to the bone marrow following systemic LNP administration in vivo. This achievement has enabled Moderna scientists to deliver mRNA directly to bone marrow HSPC in vivo, leading to HSPC transfection and long-term modulation of all hematopoietic lineages. This represents a major milestone in impacting chronic inflammatory and immune related disease.

mRNA Engineering: Optimizing Ribosome Load

The ribosome plays a central role in orchestrating the life of mRNA inside the cell. Understanding how to modulate translation by changing mRNA sequence could enable a powerful lever to control the performance of an mRNA drug. To develop such a lever, the Moderna's scientists strove to characterize mechanistically how differences in translation drive differences in protein expression. In this research, an unexpected relationship emerged where mRNAs with low translation initiation rates conferred the highest and most durable levels of protein expression. By understanding the mechanisms that drive this behavior, the Company is taking mRNA design from a guess-and-check discipline into an engineering discipline. With tools in place, and more under development, Moderna is improving its ability to make an mRNA that generates the right amount of the right protein, for the right amount of time, in the right cell type. As Moderna builds these levers into its mRNA drugs, the Company believes it will be able to target more indications with more precision.

Addressing SARS-CoV-2 Variants of Concern

One part of the Company’s strategy to remain ahead of the SARS-CoV-2 virus is to closely monitor and address emerging variants of concern and waning immunity. Moderna is using artificial intelligence (AI) and machine learning to predict escape risk. This involves developing statistical models to understand and predict escape risk, including identifying breakthrough sequences from clinical trials and real-world data, examining spike protein biophysical and pseudovirus neutralization data, studying spike mutations and lineage info, and time tracking.

Science Day Webcast Information

Moderna will host its annual Science Day for analysts and investors at 8:00 a.m. ET on Thursday, May 27. A live webcast will be available under “Events and Presentations” in the Investors section of the Moderna website at investors.modernatx.com. A replay of the webcast will be archived on Moderna’s website for one year following the presentation.

About Moderna

In 10 years since its inception, Moderna has transformed from a science research-stage company advancing programs in the field of messenger RNA (mRNA), to an enterprise with a diverse clinical portfolio of vaccines and therapeutics across six modalities, a broad intellectual property portfolio in areas including mRNA and lipid nanoparticle formulation, and an integrated manufacturing plant that allows for both clinical and commercial production at scale and at unprecedented speed. Moderna maintains alliances with a broad range of domestic and overseas government and commercial collaborators, which has allowed for the pursuit of both groundbreaking science and rapid scaling of manufacturing. Most recently, Moderna’s capabilities have come together to allow the authorized use of one of the earliest and most-effective vaccines against the COVID-19 pandemic.

Moderna’s mRNA platform builds on continuous advances in basic and applied mRNA science, delivery technology and manufacturing, and has allowed the development of therapeutics and vaccines for infectious diseases, immuno-oncology, rare diseases, cardiovascular diseases and auto-immune diseases. Today, 24 development programs are underway across these therapeutic areas, with 14 programs having entered the clinic. Moderna has been named a top biopharmaceutical employer by Science for the past six years. To learn more, visit www.modernatx.com.