HilleVax : Corporate Presentation

CORPORATE PRESENTATION

MAY 2024

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 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, 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; unstable market and economic conditions and adverse developments with respect to financial institutions and associated liquidity risk may adversely affect our business and financial condition and the broader economy and biotechnology industry; regulatory developments in the United States and foreign countries; any future impacts to our business resulting from the conflict between Russia and Ukraine or other geopolitical developments outside our control; 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 prior press releases and our filings with the Securities and Exchange Commission (SEC), including under the heading "Risk Factors" in our annual report on Form 10-K 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 hereof, and we undertake no obligation to update such statements to reflect events that occur or circumstances that exist after the date hereof. 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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HilleVax May 2024

		Clinical PoC
Norovirus has a high	Multi-billion dollar	demonstrated in
disease burden and	commercial	adults and near-term
unmet need	opportunity	large Phase IIb infant
		readout in mid-2024

Strong capital

position with $272.7M

in cash as of March

31, 2024

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Norovirus in the news…

"And these symptoms can be quite severe too. Norovirus often isn't just your typical I'm-feeling-a-little-sick-soI-may-pass-on-shuffleboard type of gastroenteritis. No, a norovirus infection can consist of projectile vomiting and explosive diarrhea. Projecting your voice, feelings, or insecurities is one thing. Projecting your vomit is something completely different."

Bruce Y. Lee, Forbes 2023

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Norovirus global annual burden is high…

~200k

Deaths

~4M

Hospitalizati

ons

~570M

• resulting in direct and indirect costs of ~$10b in US and ~$60b globally1,2

Costs

Direct						Indirect

Seek Care

~700M

Norovirus-related

illnesses

Medical

Clinical management, hospitalizations, infection control measures and cleaning, surveillance

Health

Productivity losses: sick staff work days, resources not used while managing outbreak

	Key vulnerable populations
Young children	Adults	Older adults
Endemic, incidence of	Outbreaks among	Outbreaks in nursing
norovirus highest among	HCPs, military, food	homes and hospitals, higher
young children2	handlers, travelers,	likelihood of hospitalization /
	other groups	death
1. Bartsch et al., 2016 2. Bartsch et al., 2020		5

GII.4 remains the dominant genotype associated with the majority of norovirus infections worldwide

• GII.4 infections in 2021-2022 represented approximately 60% of

infections in children <57

• GII.4 infections resulted in 75% of hospitalizations and 82% of deaths based on a meta analysis of 843 norovirus outbreaks8

• Cannon et al. Emerg Infect Dis. 2021.; 2 Fang et al. BMC Infect Dis. 2021.; 3 Lo et al. Arch Virol. 2021.; 4 Cho et al. J Med Virol. 2021.; 5 Rossouw et al. Viruses. 2021.; 6 Manouana et al. Viruses. 2021, 7NoroSurv: A global network for norovirus strain surveillance- data

retrieved on 17 Apr 2023; 8Adapted from Desai et al. CID 2012.

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HIL-214 comprises VLPs for major genotypes GI.1 and GII.4

GI.1 selected based on its potential to promote a broad immune response to

GI strains

GII.4 selected because it is estimated to be responsible for nearly two-thirds of norovirus illness1

1. Kumthip et al., 2019

1 Virus-Like Particles (VLPs)

2 Adjuvant

GI.1 VLP (Norwalk)	Consensus GII.4 VLP	Aluminum hydroxide

3 Norovirus Vaccine

Consensus Strategy

Presents epitopes from three different norovirus GII.4 strains on one VLP

Prefilled Syringe (intramuscular)

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Large clinical program demonstrates immunogenicity, efficacy, and safety/tolerability

Trial No.	Phase	Design	Study Population	HIL-214	HIL-214
		safety, n=	immuno, n=
LV01-103	I/II	R, DB, Pbo, NoV challenge for safety, immunogenicity, and efficacy	18	- 50 years	N/A1	N/A1
LV03-104	I	R, DB, Pbo, dose/age-escalation for safety and immunogenicity	18	- 85 years	66	66
LV03-105	I/II	R, DB, Pbo, NoV challenge for safety, immunogenicity, and efficacy	18	- 50 years	67	67
NOR-210	II	Study to generate serum controls for validation of serology assay	18	- 49 years	50	50
NOR-107	II	R, DB, for safety, immunogenicity, dose finding, and adjuvant justification	18	- 64 years	418	418
NOR-201	II	RD, DB for safety and immunogenicity	18	- 49 years	425	425
NOR-204	II	R, DB for safety, immunogenicity, dose finding and formulation selection	18	- >85 years	311	311
NOR-211	IIb	R, DB, Pbo for efficacy, safety, and immunogenicity	18	- 49 years;	2,355	97
military recruits
NOR-202	II	R, DB for safety, immunogenicity, dose finding and adjuvant justification	6wks - 9 years	839	839
NEST-IN12	IIb	R, DB, Pbo for efficacy, safety, and immunogenicity	5 months	1,500	1,500
NOR-1092	I	R, DB, Pbo, safety and immunogenicity	5 months	14	14
NOR-2062	II	R, DB, Pbo, safety and immunogenicity when HIL-214 is concomitantly administered with	4 months	77	77
routine infant vaccines
NOR-2152	II	SA, OL, safety and immunogenicity	18	- 49 years	185	185
TOTAL2					6,307	4,049

1.	Intranasal formulation of vaccine, not included in HIL-214 safety and immunogenicity subject numbers
2.	NEST-IN1,NOR-109,NOR-206, and NOR-215 clinical trials ongoing, final subject numbers still estimated for study completion	8
R: randomized. DB: double-blind. OL: open label. Pbo: placebo-controlled

We believe that HIL-214 clinical data have substantially de-risked the program

HIL-214 key clinical accomplishments

Dose selection

Adjuvant selection

Immunogenicity in infants/children

Immunogenicity in adults/older adults

Efficacy proof-of-concept in adults

Safety/tolerability profile across age groups

5-year safety and immunogenicity in adults

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SAFETY

>6,000 subjects (2,430 pediatric subjects) received vaccine in clinical studies

In adults, local AEs all mild/moderate with systemic AEs similar to placebo

Infant AEs largely mild to moderate with short duration (<3-4 days)

HIL-214 clinical AE profile comparable to commercial vaccines

Pediatric safety

Adult safety

NOR-202,NOR-211,NOR-204 studies, WHO, FDA prescribing information

These data are presented for informational purposes only, as
the comparisons in the tables to the right are not based on
head-to-head clinical studies and may not be comparable due
to differences in vaccine design, disease under evaluation,
trial designs and populations studied.	10