Corporate Presentation (TSX: BLU)

Roberto BelliniPresident and Chief Executive OfficerTwitter: @rbellini

July 25, 2016

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Forward Looking StatementsCertain statements contained in this presentation, other than statements of fact that are independently verifiable at the date hereof, may constitute “forward-looking statements” within the meaning of Canadian securities legislation and regulations. Such statements, based as they are on the current expectations of management, inherently involve numerous important risks, uncertainties and assumptions, known and unknown, many of which are beyond BELLUS Health Inc.'s control. Such risks factors include but are not limited to: the ability to obtain financing, the impact of general economic conditions, general conditions in the pharmaceutical industry, changes in the regulatory environment in the jurisdictions in which BELLUS Health Inc. does business, stock market volatility, fluctuations in costs, changes to the competitive environment due to consolidation, achievement of forecasted burn rate, potential payments/outcomes in relation to indemnity agreements and contingent value rights, achievement of forecasted pre-clinical and clinical trial milestones, dependence on Auven Therapeutics for the development of KIACTA™ and that actual results may vary once the final and quality-controlled verification of data and analyses has been completed. In addition, the length of the KIACTA™ development process and the sharing of proceeds between Auven Therapeutics and BELLUS Health Inc. from potential future revenue of KIACTA™ are dependent upon a number of factors, including the quantum of proceeds. Consequently, actual future results and events may differ materially from the anticipated results and events expressed in the forward-looking statements. The Company believes that expectations represented by forward-looking statements are reasonable, yet there can be no assurance that such expectations will prove to be correct. The reader should not place undue reliance, if any, on any forward-looking statements included in this presentation. These forward-looking statements speak only as of the date made, and BELLUS Health Inc. is under no obligation and disavows any intention to update publicly or revise such statements as a result of any new information, future event, circumstances or otherwise, unless required by applicable legislation or regulation. Please see BELLUS Health Inc.’s public filings with the Canadian securities regulatory authorities, including the Annual Information Form, for further risk factors that might affect BELLUS Health Inc. and its business.

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At BELLUS, we are focused on developing drugs for rare diseases starting with conditions that affect the kidneys.

Significant cash runway with multiple shots on goal

Company Highlights

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• Pipeline targeting multiple rare diseases KIACTA, partnered with US private equity fund Auven Therapeutics, has

completed a Phase 3 Study for AA amyloidosis, a rare and deadly kidney disease

KIACTA is also Phase 2 ready for Sarcoidosis, a rare lung disease

Shigamab is a monoclonal antibody preparing for Phase 2 in sHUS, a rare kidney condition that mostly affects children

• Other projects and assets Royalty on AMO Pharma’s AMO-01 in preparation for Phase 2 study in Fragile X

Syndrome

Small equity stake in niche Italian specialty pharma

Royalty on Alzheon’s drug ALZ-801 in preparation for Phase 3 study in Alzheimer’s disease

• Cash of $9.0M as of March 31st with low operational burn rate

Late stage pipeline focused mainly on developing innovative drugs for rare diseases

Pipeline and Asset Overview

ShigamabsHUS

PRECLINICAL PHASE 1 PHASE 2 PHASE 3

Wholly-owned

KIACTAAA amyloidosis Partnered (~50% economic interest)

MARKET

Partnered (~50% economic interest)KIACTASarcoidosis

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FB Health

Licensed IP (Royalty)

ALZ-801Alzheimer’s Disease

Licensed IP (Royalty)

AMO-01Fragile X Syndrome

Equity Stake (5.7%)

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A rare and deadly kidney disease with no specific treatment

FOR AMYLOID A (AA) AMYLOIDOSIS

Disease and Mechanism of Action

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CHRONIC INFLAMMATION

SERUM AMYLOID APRECURSOR (SAA) PROTEIN

AA PROTEIN + GLYCOSAMINOGLYCANS (GAGs)

ORGAN DAMAGE, IN PARTICULAR TO KIDNEYS LEADING TO DIALYSIS

REDUCTION IN FIBRIL FORMATION & DEPOSITION

Converts toAA Protein

Generatescytokine cascade

(TNFα / IL-1 / IL-6) and increases SAA levels

Rheumatic ConditionsInflammatory Bowel DiseaseChronic InfectionsFamilial Mediterranean Fever

KIACTA™ blocksAA + GAGs interaction

Systemic Amyloid A Fibril Formation & Deposition

KIACTA designed to bind AA amyloid, slow down disease progression and delay dialysis 7

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Phase 2/3 Study

New England Journal of Medicine publication of Phase 2/3 data showing KIACTA slows decline of renal function in AA amyloidosis patients

Agreement reached with FDA to conduct confirmatory Phase 3 Study

Marketing approval based on achieving comparable result of Phase 2/3 Study

Experienced and knowledgeable partner working on lead project

Auven is a global biotech private equity group

Founded by Managing Partners Stephen Evans-Freke (SUGEN, Fibrogen, Royalty Pharma) and Peter Corr (Pfizer)

Partnered on KIACTA project in 2010 All indications including AA amyloidosis

and Sarcoidosis

Funding 100% of KIACTA project including studies in AA Amyloidosis and Sarcoidosis

≥ US$70M in investments

Overall proceeds of exit expected to be shared 50-50

Auven Therapeutics Partnership for KIACTA

PARTNERSHIPBACKGROUND

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PHASE 3 STUDY- TIME TO FIRST EVENT OF RENAL FUNCTION DECLINE

PHASE 2/3 STUDY – TIME TO FIRST EVENT OF RENAL FUNCTION DECLINE

Phase 3 Study – Negative Top Line Data

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Analysis of complete dataset on-going with final assessment and next steps to be determined in 2H

201610

P=0.025

Dember et al. June 7, 2007. New England Journal of Medicine. Vol 356 (23) 2349-2360. Obici L., July 6, 2016. Presented at International Symposium of Amyloidosis.

Second KIACTA Indication – Sarcoidosis

INDICATION

DEVELOPMENT

Chronic sarcoidosis, a rare disease that causes lung scarring and decreased lung functionKIACTA target Serum Amyloid A plays key role in disease

Also partnered with AuvenLicensed IP from Mount Sinai Hospital New York

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A rare disease primarily affecting the kidneys of children

FOR STEC RELATEDHEMOLYTIC UREMIC SYNDROME (SHUS),

SHIGAMABSHIGAMAB

sHUS Disease Course and Shigamab Mechanism of Action

E. COLI INGESTION

GUT COLONIZATION AND SECRETION OF TOXIN INTO BLOODSTREAM

LONG-TERM SEQUELAE - CHRONIC KIDNEY DISEASE- HYPERTENSION

- ENCEPHALOPATHY- DEATH

10%

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SHIGAMAB BINDING NEUTRALIZES TOXIN

WHICH IS THEN ELIMINATED

90%

SPONTANEOUS RESOLUTION WITH SOME LONG-TERM SEQUELAE

INCLUDING HYPERTENSION

SHIGAMAB

TREATMENT

PROGRESSION TO HUS-HEMOLYTIC ANEMIA

-THROMBOCYTOPENIA-ACUTE RENAL FAILURE

Shigamab is a first-in-class, antibody-based therapy

for the treatment of sHUS

Shigamab: Mouse Pre-Clinical Proof-of-Concept Studies

In preclinical studies, Shigamab™ demonstrated compelling evidence as a potential treatment for sHUS:

Lead to increased survival in a lethal STEC-infected mouse model, even when treatment was delayed by up to 72 hours post-infection

Reduced kidney injury, as measured by kidney biomarkers, in Stx2-intoxication mouse model when administered up to 4 days post-intoxication

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1 2 3 4 5 6 7 8 9 10 11 1202468

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Survival in STEC Mouse Model

Control Treated 24hrsTreated 48hrs Treated 72hrs

Time (Days Post Infection)Sur

viva

l (#

anim

als)

Non-intox'd (5)

d0 Stx2 + PBS

(7)/Ab(6)

d2 Stx2 + PBS(7)/Ab(8)

d4 Stx2 + PBS(5)/Ab(6)

d6 Stx2 + PBS(5)/Ab(5)

0

100

200

300

400

500

600

700

800

Average Lipocalin-2 (NGAL) Levels (n)

PBS Shigamab

LLip

ocal

in-2

, ng/

mL

**

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Objective to evaluate the effect of delayed treatment with Shigamab on development of Stx2-induced HUS in Baboons

Shigamab administered 24h or 48h post Stx2 injection in baboons was shown to:

Rescue the animals from a lethal dose of Stx2

Reduce Stx2-induced kidney injury and protect renal function

Reduce extra-renal symptoms associated with HUS (reduced activity/alertness)

Shigamab: Baboon Pre-Clinical Proof-of-Concept

n=1 per group

Shigamab: Market Size

Estimated approximately 2,000 – 3,000 cases of sHUS annually in industrialized nations

sHUS is an ultra-orphan disease with completely unmet medical need in a primarily pediatric population

Premium pricing potential in line with comparable acute care ultra-orphan therapies

Potential peak annual sales estimated at $150M

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2000

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2011

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Cases of HUS: Italian Registry 2000-2014

MARKET SIZE

Shigamab: Clinical

SAFETY FOCUSED PHASE 2 STUDY COMPLETED

NEXT STEP: EFFICACY FOCUSED PHASE 2 STUDY

Shigamab™ was safe and well tolerated at doses 1 and 3 mg/kg in childrenNo allergic or hypersensitivity reactionsPlasma half-life = 9 days

Objective to reduce need for dialysisStudy design currently being finalized

Ingestion Colonization Toxin Secretion

-4 0 2 4 6 8-2

Shigamab intervention*

Diagnosis ofHUS

50% No need for dialysis

*within 24 hours of HUS diagnosis

Days

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Dialysis 50%

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- AMO-01 for Fragile X Syndrome (FXS)

- ALZ-801 for Alzheimer’s Disease

- Equity stake in FB Health

OTHER PROJECTS AND ASSETS

SHIGAMABOTHER

IP Licensed to AMO Pharma in 2014 in return for mid-single digit percentage royalty/revenue share

Private company located in London, UK

Clinical stage pipeline focused on the treatment of CNS and neuromuscular diseases

Founded and led by seasoned industry professionals (Novartis, Shire, GSK)

Raised US$25M in Q3 2015 from Woodford Patient Capital Trust

Small molecule Ras-ERK pathway inhibitor

Preclinical data shows AMO-01 successfully reversed abnormalities in neuronal anatomy and cognitive and behavioral deficits in transgenic mouse models of FXS

Phase 2 expected to begin in 2016

FXS is deadly disease with no current approved therapies that affects 180K patients in the US

Potential peak annual sales of $2B

AMO Pharma’s AMO-01 for Fragile X Syndrome

AMO-01AMO PHARMA

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IP licensed to Alzheon in 2013 in return for mid-single digit percentage royalty/revenue share

Private company located in Framingham, MA

Focused on Alzheimer’s disease and other neurodegenerative disorders

Founded and led by team with significant industry and Alzheimer’s success (Pfizer, Elan, CoMentis)

$10M Series A financing in April 2015

Small molecule oral inhibitor of amyloid aggregation and neurotoxicity discovered at Bellus for the treatment of Alzheimer’s disease

In preparation for Phase 3 focusing on treatment of Alzheimer’s patients homozygous for apolipoprotein E gene

Addresses multibillion dollar market opportunity

Alzheon’s ALZ-801 for Alzheimer’s Disease

ALZ-801ALZHEON, INC.

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5.7% ownership stake in FB Health currently valued at $840K

Italy based specialty pharma focused on neurology and psychiatry

Distributes over 10 nutraceutical and pharmaceutical products in Italy

Growing and profitable business

Equity stake received as partial consideration for sale of Vivimind to FB Health in 2013

Equity Stake in FB Health

FB HEALTH

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2013 2014 2015 -

1,000

2,000

3,000

4,000

5,000

6,000

7,000

FB Health Annual Sales (in €000)

Corporate

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Capital Markets as of July 25th, 2016

Ticker TSX: BLU

Shares (Basic) 61.1M

Shares (Fully Diluted) 65.9M

Daily Volume ~370K

Market Capitalization ~$15M

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Key Finance Items as of March 31st, 2016

Cash $9.0M

Net Receivables $0.2M

FB Health Investment $0.8M

Tax losses/assets $40M

Burn rate (monthly) ~$225K

Shareholder Ownership

Bellini Family ≈ 32%

Power Corporation ≈ 29%

Pharmascience ≈ 10%

Governance and Shareholders

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Board of Directors Company / Experience

Dr. Francesco Bellini (Chair)

Franklin Berger

Charles Cavell

Hélène Fortin

Pierre Larochelle

Murielle Lortie

Joseph Rus

Dr. Martin Tolar

Roberto Bellini

Management Title

Roberto Bellini President and Chief Executive Officer

Dr. Denis Garceau Senior Vice President, Drug Development

François Desjardins Vice President, Finance

Tony Matzouranis Vice President, Business Development

LAROSE FORTIN CA Inc.

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