Corporate Presentation

NYSE: ANRO

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for the Brain is Here.

Precision Medicine

OUR MISSION

Redefining psychiatry by leveraging individuals' neurobiology to develop personalized and highly effective medicines, helping patients get better faster.

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Alto by the numbers

Advancing

a leading, clinical-stage precision medicine portfolio for the brain

MILLION

Into

Patients Dosed

Across studies with Alto's novel product candidates and precision approach

Patient Impact

Opportunity across the portfolio

Mid- to Late-Stage Data Readouts

In next ~2 years

Expected Cash

Runway

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CNS is the next frontier in precision medicine

Oncology

Cardiovascular

predictive biomarkers

target specificity or genetics

CNS /

Alto is the only company taking a precision biomarker-based approach to patient identification aiming to drive better clinical outcomes in CNS

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Unmet needs pervade mental health disorders

Depression and schizophrenia are leading causes of disability worldwide

Lancet, 2017

13% of U.S.

adults take antidepressants

Brody, 2020

$280B spent on mental health services in 2020

SAMHSA

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Alto's strategy addresses a core problem in psychiatry

Characterizing drug activity and identifying responsive patient populations before advancing

Current approach

Unguided trial-and-error treatments in heterogeneous populations work poorly

Alto precision approach

Differentiated drug profile in stratified patient populations

No human target engagement

Uncontrolled and unmeasured patient heterogeneity

Broad utilization of pharmacodynamic biomarkers

Discover and prospectively replicate objective biomarkers for patient selection

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First biomarker-driven pipeline for mental health conditions

Multiple independent programs leveraging our biomarker strategy to systematically reduce development risk; all programs remain on track to achieve upcoming milestones

Phase 1

Phase 2

Phase 3

^Fast Track Designation 88

*Study qualifying as pivotal is subject to FDA feedback and review of data

Alto's suite of biomarkers designed to segment patients to

drive improved outcomes

Heterogeneous Clinical Populations

Alto Biomarker Platform

Example Alto Biomarker

Biomarker Characterized Population

Likely Responder to Alto Product Candidate

600

500 40

400

20

300

200 0

ALTO-100

Behavior Cognitive Profile

EEG

Wearable

EEG Signature

Sleep/Activity pattern

ALTO-300

Other Product Candidates

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