This corporate presentation by Roberto Bellini, President and CEO of BELLUS Health Inc (TSX: BLU), provides an overview of the company and its rare disease drug pipeline. The lead product candidate KIACTA has shown positive results in a Phase II/III trial for AA amyloidosis, a rare and deadly kidney disease with no approved treatments. BELLUS plans to complete the ongoing Phase III confirmatory trial in 2016 to support regulatory approval. The company is also developing KIACTA for sarcoidosis and has a second rare disease candidate, Shigamab, in preclinical testing for STEC related hemolytic uremic syndrome.

1. Corporate Presentation (TSX: BLU)
Roberto Bellini
President and Chief Executive Officer
Twitter: @rbellini
Spring 2015

2. Forward Looking Statements
2
Certain statements contained in this presentation, other than statements of fact that are
independently verifiable at the date hereof, may constitute forward-looking statements. Such
statements, based as they are on the current expectations of management, inherently involve
numerous risks and uncertainties, known and unknown, many of which are beyond BELLUS
Health Inc.'s control. Such risks include but are not limited to: the ability to obtain financing
immediately in current markets, the impact of general economic conditions, general conditions
in the pharmaceutical and/or nutraceuticals industry, changes in the regulatory environment in
the jurisdictions in which the BELLUS Health Group does business, stock market volatility,
fluctuations in costs, and changes to the competitive environment due to consolidation,
achievement of forecasted burn rate, and that actual results may vary once the final and
quality-controlled verification of data and analyses has been completed.
Consequently, actual future results may differ materially from the anticipated results expressed
in the forward-looking statements. The reader should not place undue reliance, if any, on any
forward-looking statements included in this news release. These statements speak only as of
the date made and BELLUS Health Inc. is under no obligation and disavows any intention to
update or revise such statements as a result of any event, circumstances or otherwise, unless
required by applicable legislation or regulation. Please see the Company’s public fillings
including the Annual Information Form of BELLUS Health Inc. for further risk factors that might
affect the BELLUS Health Group and its business

3. 3
30 million
people in the United States have a RARE disease.
Source: NIH: National Institutes of Health Office of Rare Diseases

4. 4
Only about 5%
of these people have a specific therapy
to treat their disease.

5. 5
85-90%of rare diseases are serious or life threatening.

6. Regulatory advantage
Premium pricing
Market protection
Smaller clinical trials
Efficient commercialization
strategies
6
Small patient numbers, BIG opportunity

7. 7
At BELLUS, we are focused on developing drugs for rare
diseases starting with conditions that affect the kidneys.

8. Business plan fully funded through key milestones
OVERVIEW KEY FINANCIALS
Shareholder Information
8
Public company (TSX: BLU)
based in Montreal, QC
Developing drugs for rare
diseases
Late-stage product pipeline with
fully funded business plan
Shares outstanding
(Fully Diluted): 65M
Cash (12/31/14): $12.3M
Burn rate (monthly): <$300K

9. Late stage pipeline focused on developing innovative drugs for rare
diseases
Pipeline of Products
Shigamab
sHUS
DISCOVERY PRECLINICAL PHASE I PHASE II PHASE III
KIACTA™
AA amyloidosis
MARKET
AL amyloidosis
KIACTA™
Sarcoidosis
9

10. Lead Phase III Product Candidate
10
A rare and deadly
kidney disease with
no specific treatment
FOR AMYLOID A (AA)
AMYLOIDOSIS

11. Disease and Mechanism of Action
11
CHRONIC
INFLAMMATION
SERUM AMYLOID A
PRECURSOR (SAA)
PROTEIN
AA PROTEIN +
GLYCOSAMINOGLYCANS
(GAGs)
ORGAN DAMAGE, IN
PARTICULAR TO
KIDNEYS LEADING TO
DIALYSIS
REDUCTION IN
FIBRIL FORMATION
& DEPOSITION
Converts to
AA Protein
Generates
cytokine cascade
(TNFα / IL-1 / IL-6)
and increases SAA levels
Rheumatic Conditions
Inflammatory Bowel Disease
Chronic Infections
Familial Mediterranean Fever
KIACTA™ blocks
AA + GAGs interaction
Systemic Amyloid A Fibril
Formation & Deposition

12. Patient Population
Source: Navigant Consulting 2014
10,000-
15,000
potential KIACTATM
patients in the United
States and Europe
MARKET RESEARCH
Navigant Consulting conducted
extensive primary and secondary
research including more than 60
interviews with treating physicians
and key opinion leaders in the
United States and Europe
12

13. PRICING
Orphan drug designation granted with
market protection in the U.S. (7 years),
Europe and Japan (10 years)
Intellectual property to 2026
PROTECTION
Disease with large unmet medical need
and no specific treatment
Clear pharmaco-economic
rationale due to high cost of kidney
disease
Premium pricing for comparative rare
disease drugs
Market Considerations
KIACTA is well positioned to achieve premium pricing in line with
comparable rare disease drugs 13
Drug
U.S.
Patients
Disease Price
Vyndaqel 1,500
Transthyretin amyloid
polyneuropathy
$200K
Gattex 9,500 Short Bowel Syndrome $295K
Kalydeco
1,350
Cystic Fibrosis (G551D
mutation)
$335K
Procysbi
500 Nephropathic cystinosis $250K
Juxtapid 3,000
Familial
hypercholesterolemia
$250K
Jakafi
1,500 Splenomegaly $87K
COMPARABLES

14. Increasing Number of Orphan Drug Launches…
14
0
20
40
60
80
100
120
2006-2008 2009-2011 2012-2014
Rare Disease Non-Rare Disease
U.S. Drug Launches of New Molecular Entities
Source: IMS

15. …Grabbing Increasing Share of Pharma Market
15

16. Experienced and knowledgeable partner working on lead project
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
KIACTA™ to be sold through
auction process either prior to, or
after, Phase III Confirmatory Study
results
Investment bank Lazard engaged
to explore sale of KIACTA™
Auven Therapeutics Partnership for KIACTA™
BUSINESS PLANAUVEN PARTNERSHIP
16

17. 0
5
10
15
20
25
30
35
40
45
50
Placebo
KIACTA
Composite
Endpoint (Time to
First Worse
Event)
Doubling
Serum
Creatinine
50%
Decrease
Creatinine
CIearance
Dialysis/
ESRD
NumberofWorseEvents
17
*
*
**
Strong Clinical Results in Phase II/III Study
Landmark study in AA
amyloidosis: 183 patients
treated for 2 years
Important benefits for
patients on drug:
Statistically significant
reduction in number and
risk of reaching
worsening kidney event
Important delay in
reaching dialysis
*p<0.05
**p<0.01

18. Clean safety profile without any important differences
between groups in Phase II/III study 18
KIACTA™ – Clean Safety Profile
98%
36%
23%
93%
42%
25%
0%
20%
40%
60%
80%
100%
AEs SAEs Disc due to AEs
%ofPatients
KIACTA
Placebo

19. 19
Regulatory
New England Journal of
Medicine publication
concludes that KIACTATM
slows decline of renal
function in AA
amyloidosis
Agreement reached in
U.S., Europe, Japan to
conduct Phase III
Confirmatory Study
Approval based on
achieving comparable
result of first Phase III
Study

20. Study enrolled with 260 patients
Trial concludes when 120 of 230 patients
reach event of kidney function
deterioration
More than two thirds of the events have
been reached
Study completion expected in 2016
Phase III Confirmatory Study
20

21. New KIACTA™ Indication - Sarcoidosis
INDICATION
DEVELOPMENT
Chronic sarcoidosis, a rare
disease that causes lung scarring
and decreased lung function
No specific treatment
Agreement with Mount Sinai Hospital
New York to start Phase 2 proof-of-
concept study in 2015
21

22. Second Rare Disease Product Candidate
22
A rare disease
primarily affecting
the kidneys of
children
FOR STEC RELATED
HEMOLYTIC UREMIC
SYNDROME (SHUS),
SHIGAMABSHIGAMAB

23. Disease Course and Mechanism of Action
E. COLI INGESTION
GUT COLONIZATION AND
SECRETION OF TOXIN
INTO BLOODSTREAM
TOXIN MAY BE CARRIED
BY PMNs IN
BLOODSTREAM
SYMPTOMS: BLOODY
DIARRHEA
SHIGAMAB BINDING
NEUTRALIZES TOXIN
WHICH IS THEN
ELIMINATED
Shigamab
Antibody
Day -4 Day 0 Day 4 Day 8
TOXIN BINDS TO GB3
RECEPTORS ON KIDNEY
LEADING TO STEC-HUS.
OUTCOMES:
-CHRONIC KIDNEY DISEASE /
HYPERTENSION: 40%
-ENCEPHALOPATHY / DEATH: 5%
-RESOLUTION: 55%
23
90%
SPONTANEOUS
RESOLUTION
10%
SHIGAMAB TREATMENT

24. Shigamab Overview
24
NEXT STEPS (12 MONTHS)
MARKET OPPORTUNITY
CLINICAL
Proof-of-concept for treatment of sHUS in animal models
Meetings with regulators to agree on development plan
2,000-3,000 estimated annual cases of sHUS in developed
countries, principally children
$100-200 million annual sales opportunity
Safe and well tolerated in target pediatric population

25. Shareholder Ownership
Bellini Family ≈ 30%
Power Corporation ≈ 30%
Pharmascience ≈ 10%
Governance and Shareholders
25
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.
25

26. KEY STATS
Shareholder Information
Price (52-week range): $0.44-$1.80
Daily Volume: 20K (3 month avg)
0
50,000
100,000
150,000
200,000
250,000
300,000
$0.00
$0.20
$0.40
$0.60
$0.80
$1.00
$1.20
$1.40
$1.60
$1.80
$2.00
Feb 2014 Mar 2014 Apr 2014 May 2014 Jun 2014 Jul 2014 Aug 2014 Sep 2014 Oct 2014 Nov 2014 Dec 2014 Jan 2015
BLU 1-YR STOCK PERFORMANCE (TSX)
Price Volume
RESEARCH COVERAGE
Bloom Burton (D. Martin) - $3.00
Hybridan (D. Nathan) - $6.00
Zacks (J. Napodano) - $2.50
2626

27. Potential KIACTA™ exit
Continue executing KIACTA™ for AA
Amyloidosis plan:
Completion of recruitment
Launch of open label extension
study
Market assessment
Progress rare disease pipeline projects:
IND filing for KIACTA Phase 2 for
Sarcoidosis
Animal studies to support
Shigamab Phase II
Focused on achieving short term milestones that drive long term
value for shareholders
Milestones
Past Execution
Attractive partnership
for KIACTA™
Execution of global
KIACTA™ Phase III
Confirmatory Study
Expansion of rare
disease pipeline
Strong balance sheet
and clean capital
structure
12 Month Milestones
27