STALLERGENES : 2011 Sales up 9% Market Share Gains

Regulatory News:

? million		2010				10/09		2011				11/10
		? m		%Sales		Var.%		? m		%Sales		Var.%
Southern Europe (1)		46.8		73		10		51.7		75		10
Other EU countries (2)		14.3		23		9		14.2		21		(1)
Other markets		2.6		4		71		2.9		4		11
SLIT		54.7		86		13		60.7		88		11
SCIT		7.5		12		10		6.6		10		(11)
Other products		1.5		2		(14)		1.5		2		4
Total Q4 sales		63.7		100		12		68.8		100		8
Southern Europe (1)		155.2		72		12		171.6		73		11
Other EU countries (2)		52.3		24		10		52.8		22		1
Other markets		8.8		4		32		10.6		5		20
SLIT		183.8		85		15		203.6		87		11
SCIT		25.9		12		0		25.9		11		(0)
Other products		6.6		3		(4)		5.5		2		(17)
Cumulated sales		216.3		100		12		235.0		100		9
(1) Portugal, Spain, France, Italy, Greece; (2) Switzerland included

Sales growth and financial position

During the fourth quarter of 2011, Stallergenes (Paris:GENP) achieved sales of ? 68.8 million, an increase of 8% compared to the fourth quarter of 2010. Over the full year, sales grew by 9% to ? 235 million, despite a further weak pollen season for grasses and the impact of the regulatory rebate in Germany. The sublingual route, Oralair^® particularly, continued to drive growth. Stallergenes thus consolidated its market shares within a difficult environment overall.

As for 2012, the expected adverse impact of two consecutive weak pollen seasons on sales of immunotherapy treatments to grasses, which represent about one third of consolidated sales, lead us to set our growth target in the 5% to 7% range. Growth will be strengthened by the thriving new subsidiaries, in Russia, Poland, Turkey, Australia, and Latin America. Furthermore, the registration of the Oralair^® application in the US remains one of the company's priorities.

Significant 4^th quarter transactions and events

On 1 January 2012, Stallergenes carried out the previously announced changes to its governance. Albert Saporta became Non-Executive Chairman and Roberto Gradnik was appointed Chief Executive Officer.

ABOUT STALLERGENES

Stallergenes is a European biopharmaceutical company dedicated to the treatment of allergy related respiratory diseases, such as severe rhinoconjunctivitis and rhinitis, as well as allergic asthma, using allergen immunotherapy. The seventh largest pharmaceutical company in France and the leader in sublingual immunotherapy treatment, Stallergenes devotes almost 20% of its gross turnover to Research & Development and is actively involved in the development of a new therapeutic class, sublingual immunotherapy tablets.

In 2011, the company had sales of ? 235 million, and more than 500,000 patients were treated with Stallergenes products.

Euronext Paris (Compartment B) CAC small ISIN Code: FR0000065674 Reuters Code: GEN.PA Bloomberg Code: GEN.FP

Additional information is available at: http://www.stallergenes.com

Stallergenes
Albert Saporta
Chairman
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Roberto Gradnik
Chief Executive Officer
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Christian Thiry, Chief Financial Officer
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Stallergenes Press Relations
Lise Lemonnier, Communication Officer
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Investor and Analyst Relations
Lucile de Fraguier, Pavie Finance
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