AB Science — Capital/Financing Update 2010

Apr 8, 2010

Paris, April 8th 2010, 8 am

AB Science launches its initial public offering on NYSE Euronext

• Opening of the public offering and the global offering in an indicative price range between 13,95€ and 17,05€ per share¹ :
• o a public offering in France in the form of an open price offering, principally intended for retail investors (the "OPO");
• o a global placement principally intended for institutional investors (the "Global Placement") comprising a placement in France and an international private placement in certain countries, outside of the United States of America.
• Initial size of the offering: 2.278.530 existing shares and 1.305.700 newly issued shares, or 55,5 M€ (on the basis of the mid point of the initial public offering price range)
• An extension clause : up to 537 634 existing shares
• Over-allotment option : up to 618.279 existing shares
• Subscription period is expected to end on April 20th 2010, for both the public offering and the global offering
• Final offering price expected on April 21st 2010, and trading on NYSE Euronext Paris (Compartment B) is expected on April 22th 2010

AB Science launches its initial public offering and proposed listing of it shares on NYSE Euronext Paris, Compartment B.

The French securities regulator (l'Autorité des marchés financiers – the AMF) granted visa n° 10-084 on April 7th 2010 to the prospectus relating to AB Science's initial public offering (comprising its Document de Base registered on February 10th under number I.10-006, an update of the document de base filed with the AMF on April 7th and a note d'opération).

AB Science is a pharmaceutical company specializing in the research, development and commercialization of protein kinase inhibitors (PKIs), a new class of targeted molecules whose action is to modify signalling pathways within cells. AB Science targets diseases with high unmet medical needs (especially cancer, inflammatory diseases and central nervous system diseases), in both human and veterinary medicines.

Conducted since its creation by innovation, AB Science has developed its own portfolio of molecules. Masitinib, a lead compound, has already been registered in veterinary medicine in Europe in November 2008.

Additionally, AB Science is pursuing three on-going phases 3 in human medicine in pancreatic cancer, GIST and mastocytosis.

¹ The price of the Offering may be freely set below €13.95 or so long as purchase orders could be revoked for at least two trading days, may be set above €17.05.

The Offering and the listing of the Company's shares for trading on the Euronext Paris market is intended in particular to provide the Company with additional resources to finance its operations, including:

• The financing of the clinical development of masitinib in new therapeutic indications in human medicine (multiple myeloma, multiple sclerosis, Alzheimer, rheumatoid arthritis, and asthma)
• The financing of regulatory preclinical development of new molecules issued from the Company's research

Banking syndicate

Lead manager and bookrunner Joint lead manager: Fortis Bank Nederland

Public information

The legal and financial documents required to be made available to shareholders may be consulted at the registered office of the Company, 3 avenue George V, 75008 Paris.

Copies of the Prospectus are available free of charge from the Company and from the Lead Manager and Bookrunner and the Joint-Lead Manager. The Prospectus may be viewed on the websites of the Company (www.ab-science.com) and the AMF (www.amf-france.org).

The attention of investors is drawn to Section 4, "Risk Factors", contained in the Document de base registered with the AMF, the update of such Document de base filed with the AMF and to Section 2 "Risk Factors" contained in the Note d'opération.

About AB Science

Founded in 2001, AB Science is a pharmaceutical company specializing in the research, development and commercialization of protein kinase inhibitors (PKIs), a new class of targeted molecules whose action is to modify signalling pathways within cells. Through these PKIs, the Company targets diseases with high unmet medical needs (cancer, inflammatory diseases and central nervous system diseases), in both human and veterinary medicines. Thanks to its extensive research and development capabilities, AB Science has its own portfolio of molecules. masitinib, a lead compound, has already been registered in veterinary medicine in Europe and is pursuing three on-going phases 3 in human medicine in pancreatic cancer, GIST and mastocytosis.

More information on AB Science's website: www.ab-science.com

Contact Agnès Villeret - Tel: +33 1 53 32 78 95 - agnes.villeret@citigate.fr Matthieu Pirouelle - Tel : +33 1 53 32 84 77 - matthieu.pirouelle@citigate.fr

Disclaimer

This press release, together with the material set forth herein, does not constitute an offer of securities for sale nor the solicitation of an offer to purchase securities in any jurisdiction. Distribution of such press release in certain jurisdiction may constitute a breach of applicable laws and regulation.

In particular:

This press release does not constitute an offer to sell or the solicitation of an offer to buy any financial instruments in the United States. Securities mentioned in this document have not been and will not be registered under the Securities Act of 1933, as amended (the "Securities Act") and may not be offered or sold in the United States absent registration or an exemption from the registration requirements of the Securities Act. Any public offer of securities in the United States shall be made by means of a prospectus that may be obtained from the issuer containing detailed information regarding the Company, its management and financial statements. The Company does not intend to register this offering in all or in part or to make a public offer of securities in the United States.

This press release is not an invitation nor is it intended to be an inducement to engage in investment activity for the purpose of section 21 of the Financial Services and Markets Act 2000, as amended ("FSMA"). This document is directed only at (i) persons outside the United Kingdom; or (ii) persons in the United Kingdom that are "qualified investors" within the meaning of Article 2(1)(e) of Directive 2003/71/EC including any relevant implementing measure in each member state, that are also (a) persons authorised under FSMA or otherwise having professional experience in matters relating to investments and qualifying as investment professionals under article 19 of the Financial Services and Markets Act 2000 (Financial Promotion) Order 2005, as amended (the "Financial Promotion Order"); or (b) institutions or corporations qualifying as high net worth persons under Article 49(2)(a) to (d) of the Financial Promotion Order; or (c) any other persons to whom this document for the purposes of Section 21 of FSMA can otherwise lawfully be made (all such persons together being referred to as "Relevant Persons"). Any person in the United Kingdom that is not a Relevant Person should not act or rely on this document.

This document contains forward-looking statements. No guarantee can be given as to any of the events anticipated by the forward-looking statements, which are subject to inherent risks, including those described in the Prospectus, changes in economic conditions, the financial markets or the markets in which AB Science operates.

Société Générale, acting as stabilizing agent, or any institution acting on its behalf (the "Stabilizing Agent") may, during a period of 30 days following the date on which the offering price is determined, ie, according to the indicative timetable, from April 21 to May 21, 2010, effect transactions with a view to maintaining the market price of AB Science shares in a manner consistent with applicable laws and regulations and, in particular, EU Commission regulation no 2273/03 of December 22, 2003. However, there is no assurance that the Stabilizing Agent will take any stabilizing action and, if begun, such stabilizing action may be interrupted at any time. Any stabilizing action may affect the price of AB Science shares and could result in market prices for the shares higher than those which might otherwise prevail.

SUMMARY OF THE PROSPECTUS

Approval n°10-084 of the Autorité des Marchés Financiers dated 7 April 2010

NOTICE

This summary should be read as an introduction to the Prospectus. Any decision to invest in the securities offered hereby should be based on an exhaustive examination of the Prospectus as a whole. Where a claim concerning the information contained in the Prospectus is instigated before a court, the plaintiff investor may, under the national law of the Member States of the European Community or parties to the agreement on the European Economic Area, have to bear the costs of translating the Prospectus before the legal proceedings are initiated. The people who have presented the summary, including its translation where applicable, and have requested its notification in the sense of article 212-41 of the General Regulations of the AMF, engage their civil liability only if the content of the summary is misleading, inaccurate or inconsistent when read together with the other parts of the Prospectus.

A. BASIC INFORMATION ABOUT THE ISSUER

Corporate name, sector of activity and nationality

AB Science is a limited company with Board of Directors governed by French law and operating in the pharmaceutical sector.

Overview of activities

Founded in July 2001, AB Science is a pharmaceutical company based in Paris specialised in the research, development and marketing of protein kinase* inhibitors (PKI), a new class of targeted therapeutic molecules, the action of which consists of modifying the signalling paths within the cells.

The pathologies targeted by the Company with these PKIs are pathologies with high medical need*, in cancers, inflammatory diseases and diseases of the central nervous system, in both human and veterinary medicine.

The Company has a significant portfolio of molecules. This portfolio of molecules is based on two separate patents for chemical structures issued notably in Europe and the United States. The flagship molecule of AB Science is masitinib.

Since its creation, AB Science has focused its research and development activities on programmes for the optimisation of new molecules and through the continuation of the programme for development of masitinib. Clinical studies with masitinib began at the end of 2003 and the Company has constantly pursued the reinforcement of its development teams in order to manage its clinical studies internally.

During 2007, the Company submitted to the American (FDA) and European (EMEA) health authorities an initial application for registration of masitinib in a canine cancer, mast cell tumour. Masitinib was registered by the EMEA in this indication in November 2008.

The Company initiated three Phase 3 studies in human health at the end of 2008 and beginning of 2009, in two indications in oncology – pancreatic cancer and gastrointestinal stromal tumour – and in one orphan inflammatory disease – mastocytosis.

The year 2008 was also marked by the creation of a subsidiary in the United States, wholly owned by AB Science and composed of six employees. This Company has the purpose of supporting the marketing of masitinib in animal health and assuring the monitoring of clinical studies in then U.S..

The Company stands out because of its determination to retain the maximum capacity to generate value (Fully Integrated Pharmaceutical Company), especially by conducting its own Phase III clinical studies, by maintaining control of subcontracted masitinib production and by marketing its drugs through its own sales forces or through distributors in Europe and the United States. For more comprehensive information about the Company's development model, see section 6.3.3 of the AB Science registration document registered by the AMF on 10 February 2010 under number I.10- 006.

Organisation Chart of the Company at 31 March 2010

Selected financial information

The historic financial information selected by the Company and featuring below is extracted from the consolidated accounts for the financial years closed on 31 December 2007, 2008 and 2009, prepared in compliance with IFRS.

Extracts of the Company's consolidated accounts (IFRS standards – audited):

Elements of the P&L statement in thousands of euros	31/12/2009	31/12/2008	31/12/2007
Revenues	316	1	0
Other operating income		-	-
Total income	316	1	-
Cost of sales	(150)	-	-
Marketing expenses	(988)	(507)	(72)
Administrative expenses	(1,643)	(1,390)	(940)
Research and development expenses	(5,833)	(6,099)	(6,141)
Other operating expenses	-	-	-
Operating income	(8,297)	(7,995)	(7,154)
Financial income	321	700	738
Financial expenses	(128)	(154)	(117)
Financial income / (loss)	193	546	620
Income Tax	(6)	-	-
Net income / (loss)	(8,110)	(7,449)	(6,533)
including:		0
Minority interests		-	-
Group share	(8,110)	(7,449)	(6,533)
Foreign exchange adjustment		9
Global income / (loss)	(8,110)	(7,440)	(6,533)
Net income (loss) per share - in euros	(0.28)	(266.1)1	(241.8)1
Diluted net income (loss) per share - in euros	(0.28)	(266.1)1	(241.8)1
	31/12/2009	31/12/2008	31/12/2007

Information from the balance sheet in thousands of euros

Current financial assets	3,506	9,057	9,987
Cash and cash equivalents	1,785	3,191	964
Total assets	14,086	16,281	13,947
Total current and non-current financial debts	5,328	2,445	2,098
Total net equity	1,041	8,780	7,770
Total liabilities and net equity	14,086	16,281	13,947

1 Before the shares' face value was divided by 1000 on 31 December 2009

Shareholders' equity and indebtedness

In compliance with CESR recommendations (CESR/05-054b, paragraph 127), the table below presents the unaudited situation of the shareholders' equity and indebtedness, established from financial data to 15 February 2010 in compliance with IFRS.

Unaudited consolidated situation of the Shareholders' equity and indebtedness at 15 February 2010 (IFRS):

(in thousands of euros)	15 February 2010
1. EQUITY CAPITAL AND DEBT
Total current debt
- subject to guarantees
- subject to pledges
- without guarantee or pledge	500
Total non-current debt (excluding current part of long-term debts)
- subject to guarantees
- subject to pledges
- without guarantee or pledge	4 822
Equity capital
- Share capital	288
- Statutory reserve
- Other reserves (1)	3 761
- TOTAL	4 049
- Net investment subsidies
- Regulated provisions
2. ANALYSIS OF NET FINANCIAL DEBT

(in thousands of euros)	15 February 2010
A. Cashflow	258
B. Cash equivalents
C. Investment securities	2 186
D. Cash assets (A) + (B) + (C)	2 444
E. Short-term financial receivables	4 511
F. Short-term bank debts
G. Share of medium- and long-term debts of less than one year
H. Other short-term financial debts	500
I. Short-term current financial debts (F) + (G) + (H)	500
J. Short-term net financial debt (I) - (E) - (D)	-6 455
K. Bank loans of over one year	1 000
L. Bonds issued
M. Other loans of over one year	3 822
N. Medium- and long-term net financial debt (K) + (L) + (M)	4 822
O. Net financial debt (J) + (N)	-1 633

(1) Other reserves include issue premium, conversion reserve, profit and the loss directly registered in shareholders' equity as well as income to 31 December 2009. They are not composed of income as well as the potential variation of conversion reserve and profit and loss directly registered in shareholders' equity from 1st January to 15 February 2010.

No significant change has taken place since 15 February 2010 that could affect the level of shareholders' equity excluding profit/loss and the various items of debt presented above, other than the issue of four convertible bonds with a par value of 500,000 euros each, which occurred prior to the Prospectus date, and the planned issue no later than 13 April 2010 of two convertible bonds of the same par value. These bonds shall be automatically converted into new shares at the Company's IPO.

Each share gives the right to a share, proportional to the portion of the capital it represents, in the earnings and company assets, but each preferred share (called "P") benefits from a right to receive as a priority claim over holders of common shares, in the case of a liquidation or voluntary dissolution of the Company that would leave outstanding surplus assets following liquidation, an amount equal to 2.29075 euros.

Summary of the principal risk factors specific to the Company and its activity

Investors are invited to take into consideration the risks described in chapter 4 of the registration document registered by the AMF on 10 February 2010 under the number I.10-006 (the "Registration Document"), its update and section 2 of this Prospectus before making their investment decision, and notably the following risks:

• AB Science develops tyrosine kinase inhibitors. In each of their respective indications, its products under development are at different pre-clinical and clinical stages. The development of a candidate drug is a process consisting of several long, costly and uncertain phases. The Company cannot in any way guarantee that these developments will succeed, or that they are succeeding, within timeframes compatible with the needs of the market. Any failure or delay in the development of its products could have a significant adverse effect on the activity of the Company, its results, its financial situation and its prospects.

Not for distribution directly or indirectly in the United States, Canada, Australia or Japan

• The Company's most advanced product in the development process is masitinib. The development of this candidate drug has demanded and will continue to demand from the Company considerable investments in time and financial resources, and the involvement of highly qualified staff. If the Company does not manage to develop and market its most advanced product, the Company's activity, its prospects, its financial situation, its results and its development could be significantly affected.
• The Company uses subcontractors within the framework of its activities. It entrusts to its subcontractors the manufacture and development of complex, cumbersome processes which must be closely monitored. It relies on these third parties for the manufacture of all its products, and notably its most advanced product, masitinib. In the event of rupture or deterioration in its relations with its subcontractors, the Company could be unable to weave relations with other subcontractors under acceptable commercial conditions, or even at all, which could harm its capacity to successfully produce, develop and market its products.
• The Company is dependent on third parties to supply it with various materials and chemical and biological products necessary to manufacture its candidate drugs or to conduct its clinical trials. The Company's supplies of any of these products could be reduced or interrupted. Moreover, if such interruption or reduction occurred, could the Company may be unable to find other suppliers of materials or chemical or biological products of acceptable quality, in appropriate volumes and at an acceptable cost.

Recent developments of the financial situation and prospects

See the selected financial information above.

On the date of this Prospectus, the Company had no knowledge of any trends or proven events relative to its activity which the Company may reasonably expect to significantly influence its turnover for the year 2010.

The Company is not communicating any projections or estimates of profits.

Recent events and facts

None

B DESCRIPTION OF THE OFFERING

Reason for the offering

The Offering and the listing of the Company's shares for trading on the Euronext Paris market is intended in particular to provide the Company with additional resources to finance its operations, including two objectives in particular:

• The financing of the clinical development of masitinib in new therapeutic indications in human medicine
• The financing of regulatory preclinical development of new molecules from the Company's research

It should be noted that between 63,57% and 72,45% of the offering's gross proceeds will be collected by Selling Shareholders based, in particular, on the exercise of the Extension Clause and the Over-Allotment Option.

Based on net proceeds from the capital increase for the Company of 18,63 million euros, approximately 78% of these proceeds will be allocated to the first objective, with 22% being allocated to the second. In the case the proceeds from the issue for the Company would be less than anticipated, the Company would use the proceeds to finance as a priority the first objective. In this case, it reserves the option to conduct a subsequent new capital increase or to resort to debt to finance the balance.

These proceeds do not include the amount raised of 3 million euros through the convertible bonds issue in favor of JP SPC 1 OBO Vatea Fund ("Convertible Bonds").

Structure of the Offering

It is planned that the distribution of the shares offered will be realised within the framework of a global offering (the "Offering") consisting of:

• a public offering in France in the form of an open price offering, principally intended for retail investors (the "OPO");
• a global placement principally intended for institutional investors (the "Global Placement") comprising a placement in France and an international private placement in certain countries, outside of the United States of America.

If the demand within the framework of the OPO permits, the number of shares allocated in response to the orders issued within this framework will be at least equal to 10% of the total number of shares offered (before exercise of the Extension Clause and Over-Allotment Option).

Nature and number of securities for which admission is requested and securities offered

	The shares to be admitted to trading on the Euronext Paris market include all of the shares comprising the share capital, namely 29 030 053 shares. The shares covered by the Offering correspond to:
	- 1 305 700 new shares to be issued in the Offering, representing approximately 4,3% of the capital and voting rights after the capital increase and the conversion of Convertible Bonds.
	- 2 278 530 existing shares representing approximately 7,5% of the capital and voting rights after the capital increase and the conversion of Convertible Bonds, which may be raised to a maximum of 3 434 443 shares, which is approximately 11,3% of the capital and voting rights after the capital increase and the conversion of Convertible Bonds, in the event of a full exercise of the Extension Clause and the Over-Allotment Option.
Extension Clause	A maximum of 537 634 existing shares (the "Extension Clause").
Over-Allotment Option	A maximum of 618 279 existing shares (the "Over-Allotment Option")
	Exercisable by the Lead Manager and Bookrunner, in the name and on behalf of the Underwriters, from 26 April to 21 May 2010.
Selling Shareholders

Number of shares sold

(before exercise of the Extension Clause and the Over-Allotment Option) Number of shares sold

(after exercise of the Extension Clause and the Over-Allotment Option)

Shareholders
Moussy, Alain	16 000	16 000
Kinet, Jean Pierre	2 000	2 000
Bioparticipations	563 198	868 779
Parande SAS	252 416	384 688
Tanamera	191 251	291 576
Lafferty	74 708	113 898
Forga	37 437	57 075
Jean Caraux	135 525	206 618
Philippe Girault	45 315	69 086
Beveguissimo eurl	157 332	239 864
Pagapa sprl	157 332	239 864

TOTAL	2 278 530	3 434 443
Auclair, Christian	1 000	1 000
Guy, Laurent	6 000	6 000
Dubreuil, Patrice	2 000	2 000
Hermine, Olivier	7 000	7 000
Deseille, Patrice	3 628	5 531
Dassault, Thierry	5 277	8 045
Sassi, Renaud	6 102	9 303
Philippe Guy	7 092	10 811
d'Angerville, Guillaume	7 256	11 062
Marchal, Olivier	13 193	20 114
Polignac, Princesse C. de	21 604	32 938
Pierre Dominique Verspieren	25 892	39 475
Litzler, Marc	28 354	28 354
CIC Investissement	36 779	60 133
Strackmann , Rémy	32 192	32 192
Mulliez, Vincent	27 000	27 000
Serge Dassault	47 497	72 412
Enver	57 062	86 995
Applied Biology Company	76 357	116 412
CIC - FCPI	93 729	153 248
Philippe Oddo eurl	141 005	214 972

Indicative price range	Between 13,95 and 17,05 euros per share (the "Price of the Offering").
	The Price of the Offering may be fixed outside of this price range. In the event of change to the upper limit of the range or in the event of fixing of the Price of the Offering above the range (initial or, where applicable, amended), the closing date of the OPO shall be deferred or a new period of subscription to the OPO shall then be opened, as the case may be, such that at least two trading days pass between the date of publication of the financial notice indicating this change and the new closing date of the OPO. Orders issued within the framework of the OPO before publication of the abovementioned financial notice will be maintained except where they are expressly revoked on or before the new closing date of the OPO. The Price of the Offering may be freely fixed below the price range (in the absence of significant impact on the other characteristics of the Offering).
Method of fixing the price of the new shares to be issued and the shares sold	The Price of the Offering shall result from matching the offering of shares within the framework of the Global Placement and the requests issued by the investors in accordance with the technique of "bookbuilding" as developed by professional practice. The Prospectus contains information relative to the method of valuation called "stock market comparables" which aims to compare the Company to listed companies of its sector presenting similar activity models, such as Nicox or Transgène.
	This method is provided strictly for guideline purposes and does not under any circumstances set the Price of the Offering.
Rights Entitlement (date de jouissance) - Date of existing shares and new shares to be issued	st January 2010. 1
Gross Proceeds from the issue	Approximately 20,24 million euros(1)(2)
Net Proceeds from the issue	Approximately 18,6 million euros(1)(2)(3)
Gross Proceeds from the sale	35,32 million euros(1), which may be raised to 53,23 million euros(1) in the event of a full exercise of the Extension Clause and the Over-Allotment Option.
Net Proceeds from the sale	32,76 million euros(1), which may be raised to 49,61 million euros(1) in the event of a full exercise of the Extension Clause and the Over-Allotment Option(3)
Underwriting	The Offering, on the date of fixing of the Price of the Offering (which is, according to the indicative timetable, on 21 April 2010), will be subject to an underwriting agreement entered by the Company, the selling shareholders, Société Générale and Fortis Bank Nederland (the "Underwriters"). This underwriting agreement may be terminated by the Underwriters up to (and including) the date of settlement/delivery, under certain circumstances (see section 5.4.3 hereafter), in which case the Offering and the capital increase will be cancelled.

Lock-up provisions For the Company: From the date of signature of the underwriting agreement and for 180 calendar days following the date of settlement/delivery, subject to certain exceptions (see section 7.3 hereafter).

For the selling shareholders for 180 calendar days, subject to certain exceptions (see section 7.3 hereafter).

For the founding shareholders for 12 months, subject to certain exceptions (see section 7.3 hereafter).

Finally, JP SPC 1 OBO Vatea Fund has undertaken to lock-up 245,000 shares for 180 days from the shares' listing on the NYSE Euronext Paris market.

• (1) On the basis of an offering price equal to the median point of the indicative price range, namely 15,50 euros.
• (2) These proceeds do not include proceeds from the subscription of the Convertible Bonds.
• (3) With the exception that the Selling Shareholders take care of the total legal and administrative fees corresponding to the share of the Shares Sold in the Offering, which are approximately 0,65 millions euros.

C DISTRIBUTION OF SHARE CAPITAL

	Holding before sale		Holding after sale (before exercise of the Extension Clause and the		Holding after sale (after exercise of the Extension Clause and the
	Number of	% of capital	Over-Allotment Option) Number of	% of capital	Over-Allotment Option) Number of	% of capital
Shareholder	shares and voting rights	and voting	shares and voting rights	and voting	shares and voting rights	and voting
		rights		rights		rights
Moussy, Alain*	12 918 999	44,83%	12 902 999	42,53%	12 902 999	42,53%
Moussy, Patrick	1 000	0,00%	1 000	0,00%	1 000	0,00%
Kinet, Jean Pierre*	264 000	0,92%	262 000	0,86%	262 000	0,86%
Bioparticipations	3 400 000	11,80%	2 836 802	9,35%	2 531 221	8,34%
Paillaud, Guy	1 000	0,00%	1 000	0,00%	1 000	0,00%
Chambon, Pierre	1	0,00%	1	0,00%	1	0,00%
Parande SAS	1 516 000	5,26%	1 263 584	4,17%	1 131 312	3,73%
Other investors	10 714 000	37,18%	9 484 136	31,26%	8 766 077	28,90%
Public	0	0,00%	3 584 230	11,82%	4 740 143	15,6%
TOTAL	28 815 000	100,00%	30 335 753	100,00%	30 335 753	100,00%
Moussy, Alain*	12 918 999	44,83%	12 902 999	42,53%	12 902 999	42,53%

Moussy, Patrick	1 000	0,00%	1 000	0,00%	1 000	0,00%
Kinet, Jean Pierre*	264 000	0,92%	262 000	0,86%	262 000	0,86%
Bioparticipations	3 400 000	11,80%	2 836 802	9,35%	2 531 221	8,34%

* These shareholders are party to a shareholders' agreement pursuant to which they act in concert.

D Dilution

	Share of shareholders' equity (in euros) (1) (3)
In euros	Non-diluted basis	Diluted basis(2)
Before issue of new shares	0,14	1,49
After issue of new shares	0,75	1,95

(1) On the basis of the total number of shares, including ordinary and preferred shares.

(2) Assuming all stock options (exercisable or not), all warrants, all BCEs (founder stock warrants) and convertible bonds (including convertible bonds that can be subscribed up to 13 April 2010) are exercised.

(3) With the exception that the Selling Shareholders take care of the total legal and administrative fees corresponding to the share of the Shares Sold in the Offering, which are approximately 0,65 millions euros.

A shareholder holding, on the date of this Prospectus, 1% of the capital (namely 288 150 shares) of the Company and not participating in the capital increase would hold, after issue of 1 305 700 New Shares, 0,96% of the Company's share capital.

E PRACTICAL DETAILS

Indicative timetable of the Offering

7 April 2010	AMF approval of the Prospectus
8 April 2010	NYSE Euronext notice relative to the opening of the OPO
	Opening of the OPO and the Global Placement
20 April 2010	Close of the OPO and the Global Placement
21 April 2010	Fixing of the final Price of the Offering and potential exercise of the Extension Clause
	Signing of the underwriting agreement
	Press release indicating the Price of the Offering and the result
	NYSE Euronext notice relative to the result of the OPO and the Global

	Placement
	First listing and start of any stabilisation period
22 April 2010	Start of trading on Euronext Paris
26 April 2010	Settlement/delivery
21 May 2010	Deadline for exercising the Over-Allotment Option
	End of stabilisation period

Terms of Purchase

Anyone wishing to participate in the OPO must deposit their orders with a financial intermediary authorised in France no later than 20 April 2010 at 17:00 (Paris time).

In order to be taken into account, orders issued within the framework of the Global Placement must be received by the Lead Manager and Bookrunner and the Joint-Lead Manager no later than [20 April] 2010 at 17:00 (Paris time).

Lead Manager and Bookrunner

Société Générale Corporate & Investment Banking

Joint-Lead Manager Fortis Bank Nederland Investor Contact

Mr Laurent Guy, CFO Telephone: +33.1.47.20.00.14

investisseurs@ab-science.com

Documents accessible to the public

The legal and financial documents required to be made available to shareholders may be consulted at the registered office of the Company, 3 avenue George V, 75008 Paris.

Copies of the Prospectus are available free of charge from the Company and from the Lead Manager and Bookrunner and the Joint-Lead Manager. The Prospectus may be viewed on the websites of the Company (www.ab-science.com) and the AMF (www.amf-france.org).