HilleVax : Corporate Presentation

CORPORATE PRESENTATION

MAY 2022

Disclaimer

We caution you that this presentation contains forward-looking statements of HilleVax, Inc. ("HilleVax," "we," "us" or similar terms). All statements other than statements of historical facts contained in this presentation, including statements regarding our future results of operations and financial position, business strategy, research and development plans, the anticipated timing, costs, design and conduct of our planned and potential clinical trials and preclinical studies for HIL-214 and any future vaccine candidates, the timing and likelihood of regulatory filings and approvals for HIL-214 and any future vaccine candidates, our ability to commercialize our vaccine candidates, if approved, the impact of COVID-19 on our business, the pricing and reimbursement of our vaccine candidates, if approved, the potential to develop future vaccine candidates, the potential benefits of strategic collaborations and our intent to enter into any strategic arrangements, the timing and likelihood of success, plans and objectives of management for future operations and future results of anticipated product development efforts, are forward-looking statements. In some cases, you can identify forward-looking statements by terminology such as "may," "will," "should," "expect," "plan," "anticipate," "could," "intend," "target," "project," "contemplates," "believes," "estimates," "predicts," "potential" or "continue" or the negative of these terms or other similar expressions. The inclusion of forward-looking statements should not be regarded as a representation by us that any of our plans will be achieved. Actual results may differ from those set forth in this presentation due to the risks and uncertainties inherent in our business, including, without limitation: we currently depend entirely on the success of HIL-214, our only vaccine candidate, and we have not yet completed any clinical trials of HIL-214; potential delays in the commencement, enrollment, and completion of clinical trials and preclinical studies; our dependence on third parties in connection with manufacturing, research and clinical and preclinical testing; unexpected adverse side effects or inadequate immunogenicity or efficacy of HIL-214 or any future vaccine candidates that may limit their development, regulatory approval, and/or commercialization; unfavorable results from clinical trials; results from prior clinical trials and studies not necessarily being predictive of future results; our ability to maintain undisrupted business operations due to the COVID-19 pandemic, including delaying or disrupting our clinical trials, manufacturing and supply chain; regulatory developments in the United States and foreign countries; our reliance on intellectual property rights under our license agreement with Takeda Vaccines, Inc.; our ability to obtain, maintain and enforce intellectual property protection for our vaccine candidates; we may use our capital resources sooner than we expect; and other risks described in our filings with the SEC, including under the heading "Risk Factors" in the prospectus we filed with the SEC on April 29, 2022 and any subsequent filings with the SEC. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date of this presentation, and except as required by applicable law, we do not plan to publicly update or revise any forward-looking statements contained herein, whether as a result of any new information, future events, changed circumstances or otherwise. All forward-looking statements are qualified in their entirety by this cautionary statement, which is made under the safe harbor provisions of the Private Securities Litigation Reform Act of 1995.

This presentation also contains estimates and other statistical data made by independent parties and by us relating to market size and growth and other data about our industry. This data involves a number of assumptions and limitations, and you are cautioned not to give undue weight to such estimates. In addition, projections, assumptions, and estimates of our future performance and the future performance of the markets in which we operate are necessarily subject to a high degree of uncertainty and risk. These and other factors could cause results to differ materially from those expressed in the estimates made by the independent parties and by us.

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Significant unmet medical need. Norovirus causes 700M illnesses and 200k deaths worldwide each year1

Clinical PoC demonstrated. Phase 2b field efficacy trial demonstrated clinical proof of concept in adults

Excellent safety profile. Well-tolerated in clinical trials of over >4,500 subjects

Large commercial opportunity. Potential multi-billiondollar commercial opportunity

Seasoned leadership team. World-classvaccine experience

1. Bartsch et al., 2016

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Senior Leadership

Rob Hershberg, MD, PhD

CEO & Chair

EVP BD & CSO, Celgene

CEO, VentiRx

CMO, Dendreon

Aditya Kohli, PhD

COO

CBO, Phathom Pharma

VP BD, Scout Bio

Engagement Manager, McKinsey

David Socks

CFO & CBO

CEO & CFO, Phathom Pharma

COO, Incline Therapeutics

SVP, Cadence Pharmaceuticals

Astrid Borkowski, MD, PhD

Chief Medical Officer

Takeda Vaccines, Novartis Vaccines

Kaia Agarwal

SVP Regulatory Affairs

Novartis Vaccines, Genzyme

Steve Lamola, MD

VP Clinical Development

PATH, Gilead

David Swerdlow, MD

VP Medical Affairs

Pfizer Vaccines, CDC

Shannon Harris, PhD

VP Clinical Assays

Seqirus, Pfizer Vaccines

Wendy Talbott

VP Clinical Operations

Novavax, Takeda Vaccines

Anju Chatterji, PhD

SVP Technical Operations

Catalyst, Exelixis, Novartis Vaccines

Chris Broomell, PhD

VP Technical Operations

Aura Bio, Takeda Vaccines

Tara Raab

VP Quality

Atara, Seqirus, Novartis Vaccines

Paul Bavier, JD

GC and CAO

Velos, Avedro

Shane Maltbie, CPA

VP Finance

TScan, Axcella

Lynn Ferrucci

VP Human Resources

Ziopharm, Clinical Data

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Board of Directors

Shelley Chu, MD, PhD

Partner, Lightspeed

Gary Dubin, MD

President, Global Vaccine Business Unit, Takeda

Julie Gerberding, MD, MPH

President, Merck Vaccines

Director, CDC

Patrick Heron

Managing General Partner, Frazier

Rob Hershberg, MD, PhD, Chair

Co-founder & CEO, HilleVax

EVP BD & CSO, Celgene

Jeri Hilleman

Audit chair/CFO of multiple public life sciences companies

Aditya Kohli, PhD

Co-founder & COO, HilleVax

Jaime Sepulveda, MD, PhD, MPH

Exec Dir, UCSF Institute for Global Health Sciences

Director, NIH Mexico

Susan Silbermann

President, Pfizer Vaccines

President, Pfizer Emerging Markets

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