ERYTECH Corporate Presentation Jefferies 2015 Healthcare Conference New York, June 4, 2015 Gil Beyen, Chairman & CEO

Forward Looking Statements

This document does not constitute or form part of any offer or invitation to sell or issue, or any solicitation of any offer to purchase or subscribe for, any shares in the Company, nor shall any part of it nor the fact of its distribution form part of or be relied on in connection with any contract or investment decision relating thereto, nor does it constitute a recommendation regarding the securities of the Company.

This document may contain forward-looking statements and estimates made by the Company, including with respect to the anticipated future performance of ERYTECH and the market in which it operates. They include all matters that are not historical facts. Such statements, forecasts and estimates are based on various assumptions and assessments of known and unknown risks, uncertainties and other factors, which were deemed reasonable when made but may or may not prove to be correct. Actual events are difficult to predict and may depend upon factors that are beyond the Company's control. Therefore, actual results, the financial condition, performance or achievements of ERYTECH, or industry results, may turn out to be materially different from any future results, performance or achievements expressed or implied by such statements, forecasts and estimates. Forward-looking statements, forecasts and estimates only speak as of the date of this document and no representations are made as to the accuracy or fairness of such forward-looking statements, forecasts and estimates. ERYTECH disclaims any obligation to update any such forward-looking statement, forecast or estimates to reflect any change in the Company’s expectations with regard thereto, or any change in events, conditions or circumstances on which any such statement, forecast or estimate is based.

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A late-stage orphan oncology company

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Targeting markets with high unmet medical needs

Acute leukemia Selected solid tumors Seven orphan drug designations

Highly innovative and industrialized technology

Encapsulation of therapeutic compounds in red blood cells Broad application potential Strong IP protection

Late stage clinical pipeline Positive Phase III results ALL

Expanded Access Program in ALL Phase IIb in AML >70% accrued Phase II in pancreas cancer Phase I/II in ALL in US

Solid corporate basis Listed on Euronext (ERYP.PA) and

OTC US – ADR1 (EYRYY) EUR 34 million cash (31/03/15) Partnerships with Recordati in Europe and TEVA in Israel in AL

ALL: Acute Lymphoblastic Leukemia; AML: Acute Myeloid Leukemia; AL: Acute Leukemia

Innovative and versatile technology platform

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Entrapment of drug substance inside red blood cells (RBC) using hypotonic/hypertonic stress

Proprietary ‘osmotic fragility’ process ensures quantifiable amounts of drug are captured in each RBC batch Protected by 13 patent families Industrialized in commercial scale GMP manufacturing facility

Resealing (hypertonic stress)

Controlled lysis (hypotonic stress)

Industrialized solution ready for the commercial phase

► Robust & reproducible: >500 batches administered with 100% delivery ► Centralized EU GMP production facility in Lyon, France, for clinical and commercial

production. Sized for the first two years of marketing. GMP & ISO certified ► US production facility in Philadelphia, at the premises of the American Red Cross,

validated for clinical trial production

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Photo salle de contrôle

Automated process

Purchase of pack of compatible RBCs and API

Preparation 2

Sourcing 1

Batch release

Identification of the key

parameters*

Encapsulation 3 4

Ca 3 hours

* Measurement of osmotic fragility, verification of blood typing, expiry date, volume, hematological parameters.

Quality control

Release by QP

Min ca 6 hours

Prescription Patient

Asparaginase: an essential weapon against acute leukemia, but toxic

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The principle Tumor starvation

The key nutrient: Asparagine

The weapon: Asparaginase

Starving cancer cells by affecting their supply of essential nutrients

Asparagine, essential nutrient for most tumor cells, but not for normal cells

Asparaginase, degrades asparagine and deprives tumor cells of key nutrient

The issues: Toxicity and

short half-life

Asparaginase can cause severe side effects (allergies, coagulation disorders and pancreas/liver problems) especially in fragile patients

Asparaginase has a short half-life (<1 day; high dose and frequent administrations need)

Proven efficacy in ALL; cornerstone in all pediatric ALL treatment protocols

Encapsulation of asparaginase: ERY-ASP/GRASPA®, a novel ‘bioreactor’

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The circulating asparagine is actively pumped into the red blood cell… Y

Y

Asparagine

Asparaginase

Antibodies

The RBC membrane prevents interactions between the asparaginase and the antibodies

Longer half-life Less toxicity

The asparaginase is definitively encapsulated in the red blood cell

…where the encapsulated asparaginase destroys it

Targeting the unmet need of fragile acute leukemia patients

82% of patients with acute leukemia receive little or no treatment with existing asparaginases

8 Source: Erytech; Jazz Pharmaceutical/ European and US data

Children Adults Seniors

Unmet need: >$ 1 billion

Addressed needs: $ 300 m

“AML”

34,000 new cases per year

“ALL”

16,000 new cases per year Native asparaginase ($ 15 m)

PEG-asparaginase - Oncaspar® ($ 95 m) Erwinase® ($ 200 m)

18% of patients

82% of patients

Children Adults Seniors

GRASPA 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016

ALL - Europe Adults & children in relapse

ALL - France Adults >55 yrs first line

ALL - France Children & adults at risk

ALL – US Adults > 40 yrs in first line

AML – Europe Seniors > 65 years in first line

Phase IIb

Phase I/II

Late stage clinical development: 6 trials in acute leukemia

In Acute Lymphoblastic Leukemia (ALL) ► European pivotal Phase II/III trial completed with positive results (N = 80) ► Expanded Access Program (EAP) for patients intolerant to current asparaginases ► Phase I/II ongoing in US; 3 centers enrolling (N = 12 to 18)

In Acute Myeloid Leukemia (AML) ► More than two thirds of patients recruited in Phase IIb trial (N = 123) ► Positive DSMB safety reviews on first 30 and 60 patients

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9

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Phase I/II

Phase II Filing

Marketing authorization

Completed Ongoing

Phase II/III

EAP

ALL – Pivotal trial: study design

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A multicentre, randomized, Phase II/III study, evaluating efficacy and safety of erythrocytes encapsulating L-asparaginase (ERY001-GRASPA®) versus reference L-asparaginase treatment in combination with standard chemotherapy in patients

with first recurrence of Philadelphia negative Acute Lymphoblastic Leukemia

• N = 80 (1 - 55 years).

• Ph-negative ALL

• First ALL relapse

• PS score ≤ 2. RA

ND

OM

IZE

1:1 GRASPA - ERY001

+ Chemotherapy

L-ASP + Chemotherapy

No allergy

GRASPA - ERY001 + Chemotherapy

Known allergy to L-ASP

ALL - Pivotal trial: both primary endpoints met with high significance

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Endpoint Non-allergic patients Allergic pts

GRASPA N=26

Ref L-aspa N=28

GRASPA N=26

Number (%) of patients who experienced ≥ 1 hypersensitivity reaction during induction**

0 (0%) 13 (46%) 3 (12%)

Number (%) with severe hypersensitivities (Grade ≥ 3)

0 (0%) 7 (25%) 0 (0%)

Mean duration of asparaginase activity above 100 IU/L during induction treatment**

20.5 days 9.4 days 18.6 days

** statistically significant (p<0.001)

ALL - Pivotal trial: favorable overall safety profile

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Summary of adverse events (AE) reported during indiction

Non-allergic patients Allergic pts

GRASPA N=26

Ref L-aspa N=28

GRASPA N=26

Patients with at least 1 AE 25 (96) 28 (100) 26 (100) Patients with at least 1 drug-related AE 18 (69) 28 (100) 16 (62) Patients with drug-related Grade ≥3 AE 13 (50) 25 (89) 11 (42) Patients with SAE 11 (42) 15 (54) 8 (31) Patients with at least 1 drug-related SAE 1 (4) 7 (25) 2 (8)

Patients with AE leading to discontinuation 0 12 (43) 0

Patients with AE outcome of death 0 4 (14) 1 (4)

ALL - Pivotal trial: favorable overall safety profile

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Key AEs of interest in >10 % of patients during induction

Non-allergic patients Allergic pts GRASPA

N=26 Ref L-aspa

N=28 GRASPA

N=26 Impaired coagulation parameters 9 (35%) 24 (86%) 15 (58%)

Hypofibrinogenemia 7 (27%) 19 (68%) 9 (35%) Anti-thrombin III decreased 2 (8%) 20 (71%) 6 (23%)

Activated PT time prolonged 1 (4%) 3 (11%) 3 (11%) Prothrombin level decreased 0 (0%) 3 (11%) 0 (0%)

Study drug-related coagulation events 9 (35%) 23 (82%) 9 (35%) Pancreatic events 8 (31%) 14 (50%) 8 (31%)

Biochemical pancreatitis 8 (31%) 14 (50%) 8 (31%) Clinical pancreatitis 2 (8%) 2 (7%) 0 (0%)

Study drug-related pancreatic events 7 (27%) 14 (50%) 7 (27%) Hepatic event 12 (46%) 14 (50%) 14 (54%)

Transaminase increased 9 (35%) 9 (32%) 8 (31%) GGT increased 4 (15%) 3 (11%) 6 (23%)

Bilirubin increased 2 (8%) 6 (21%) 2 (8%) Hepatotoxicity 2 (8%) 6 (21%) 6 (23%)

Study drug-related hepatic events 5 (19%) 12 (43%) 7 (27%)

ALL – Pivotal trial: improved clinical benefit

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Endpoint Non-allergic patients Allergic patients

ERY001 N=26

Ref L-aspa N=28

ERY001 N=26

Complete Remission rate (CR)* 17 (65%) 11 (39%) 14 (54%)

Minimum Residual Disease <10-3 9 (35%) 7 (25%) 7 (27%)

12 month Overall Survival (OS) 76.9% 67.9% 50.0%

12 month Event Free Survival (EFS) 64.9% 48.6% 50.3%

* statistically significant (p < 0.05)

ALL - Positive Phase III results: conclusions and next steps

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Key conclusions:

► GRASPA is a safe and efficacious asparaginase for the treatment of patients with relapsed ALL Reduced risk of allergic reactions Longer asparaginase activity Favorable overall safety profile Improved clinical benefit

► Favorable result in patients with prior hypersensitivity reactions

Submission for EU Marketing Authorization Application ongoing

Important validation of ERYTECH’s encapsulation technology and basis for broadening the indication and further leveraging the product and platform in other oncology indications

ALL - Expanded Access Program: treating ‘double allergic’ patients

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The expanded access program (#NCT02197650) was set up to provide access to GRASPA® to ALL patients, in first line or relapse, who are at risk of hypersensitivity reactions due to previous allergies to both the E. Coli and Erwinia derived asparaginases.

Initial results presented at ASH

Positive DSMB on first 7 patients treated ► ‘double allergic’ patients (prior allergies to E.Coli and Erwinia derived

asparaginases) ► Children and adults ► First line and relapse

12 patients enrolled to date. Program will be open until Marketing Authorization

ALL - Phase I/II study ongoing in the US

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Open label dose escalation study with ERY-ASP in 12 to 18 adult ALL patients over 40 years of age in frontline therapy

Participating centers ► University of Chicago – Richard Larson (Principal Investigator) ► Duke Medical Center ► University of Ohio Medical Center ► Other sites being opened

Discussion with FDA being prepared to accelerate study and discuss overall development plan

Additional indication for GRASPA®, AML in Phase IIb

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AML, a logical extension of indication ► Large unmet medical need: est. 34.000 new patients per year (US & EU) ► Predominantly senior patients (median age: 67 years), where the favorable

safety profile of GRASPA® may be a particular advantage ► Most AML blasts are deficient in ASNS activity and have shown to be sensitive

to asparaginase ► Increased CR rates observed with asparaginase in AML (Cappizi ea, 1988)

Phase IIb study ongoing in AML patients over 65 years of age in Europe ► Multinational, randomized Phase IIb study (N=123), comparison of GRASPA®

plus low dose cytarabine versus low dose cytarabine alone ► More than two-thirds of patients recruited ► Positive safety evaluations by DSMB on 30 and 60 patients

Partnerships established for commercialization in acute leukemia

Licensing deal with Recordati – Orphan Europe for Europe ► Commercialisation of GRASPA® in ALL and AML in Europe ► Up to ca. € 50 million in payments (upfront, development

funding and milestones) ► € 5 million equity participation in the IPO ► Up to 45% of net sales retained by ERYTECH (transfer price

+ royalties)

Licensing deal with TEVA for Israel ► Commercialisation of GRASPA® in ALL in Israel ► 50:50 revenue sharing agreement

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Mode of action confirmed in other oncology indications

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Asparagine synthetase

(ASNS) expression of tumors

Source: Dufour e.a. , Pancreas 2012 (in collaboration with MD Anderson Cancer Center Houston)

Tumors sensitive to asparagine depletion

Pancreas cancer: Phase II trial ongoing

One of most agressive cancers. Ca 125.000 new patients per year in Europe and the USA; 5 year overall survival <10%

Phase I study performed in 12 patients ► Monotherapy in dose escalation; single injection ► No dose limiting toxicities ► Conclusion: ERY-ASP given in last line therapy is well tolerated even at the

highest dose (150 IU/kg)

72% of >600 biopsies analyzed have no or low expression of ASNS

Phase II study launched to evaluate efficacy in association with current chemotherapy and with a stratification of patients based on expression of ASNS ► Ca 90 patients in second line treatment ► 2-to-1 randomization to standard chemotherapy alone ► DSMB on first 24 patients expected mid 15

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NH Lymphomas represent a large unmet medical need: ca 180.000 new cases per year in Europe and the US combined

NH Lymphomas: preparing Phase II study in DLBCL

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L-asparaginase is well known to physicians treating lymphomas. Particular need and rationale in Diffuse Large B-Cell Lymphoma (DLBCL) representing 30-40% of all Non-Hodgkin Lymphomas

More than 85% of DLBCL biopsies analyzed have been shown to be ASNS deficient (sensitive to asparaginase)

Based on the available data in acute leukemia, ERYTECH is preparing a Phase II study in DLBCL for launch in 2015 in Europe

0%

25%

50%

75%

100%

DLBCL (n=110)

Tumors sensitive to asparagine

depletion (no/low ASNS)

Other enzymes to strengthen the personalized medicine approach

At least two other amino acids and their respective enzymes have been identified as relevant for ‘tumor starvation’ treatments

Asparaginase Methionine-γ-liase

Arginine-deaminase

Leukemia Lymphoma Myeloma Pancreas

Liver Bladder Ovary Lung

Colorectal …

CNS & Brain Leukemia

Lung Pancreas Colorectal Melanoma

Gastric Prostate

…

Liver Melanoma Leukemia Sarcoma Pancreas

Lymphoma …

Indications

Enzymes

ERYTECH is the lead partner in a syndicate R&D program and benefits from €7M government funding over 7 years to develop additional encapsulated enzyme products with their companion tests and bring them to the clinic ERY-MET, methioninase in RBCs, identified as promising new product candidate. Start of Phase I clinical trial aimed in 1H 2016

Solid cash balance and shareholder base

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€ 30 M raised in private placement end October 2014 68% from specialized US investors

Cash balance 31/12/2014: € 37 M 31/03/2015: € 34 M

Net cash consumption (in operating and investing activities) 2014: € 7.6 M 1Q15: € 3.0 M

Capital structure (fully diluted):

Shares outstanding: 6,882,761 Stock options: 557,180

Management 8%

Auriga Venture

16%

Idinvest 5 %

Free float 57%

Recordati 6%

Baker Bros 9%

2014 2015 2016 - 2017

Launch Phase II solid tumor study: pancreas

First patient US ALL study

2nd DSMB Phase IIb AML study

Results Phase III ALL study

€30 M capital increase

Dense news flow and significant value inflection points ahead

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Launch ERY-MET Phase I trial

EU marketing authorization ALL

Results Phase II pancreas cancer

Results US Phase I/II ALL study

Results Phase IIb AML study

ADR level 1 listing

DSMB Pancreas cancer Phase II study

DSMB AML Phase II study

EU MAA submission ALL

Updates on US Phase I/II ALL study and development plan

Launch Phase II in NH Lymphoma

Thank you

ERYTECH Pharma SA 60 Avenue Rockefeller 69008 Lyon France www.erytech.com investors@erytech.com