News Release

Siegfried (USA) Inc. and Jazz Pharmaceuticals sign Supply Agreement

Siegfried (USA) Inc is pleased to announce that on April 1, 2010, a Supply Agreement with Jazz Pharmaceuticals Inc. was signed. Siegfried has the right to supply at least 60% of Jazz Pharmaceutical’s worldwide requirements of sodium oxybate, the active pharmaceutical ingredient in Xyrem® (sodium oxybate) oral solution, pending DEA registration, quota approval and FDA approval as a manufacturer.

Siegfried will carry out all required process transfer and manufacturing at Siegfried (USA) Inc.’s FDA and DEA registered site in Pennsville, NJ. Commercial manufacture of sodium oxybate is expected to commence after Siegfried obtains the required DEA and FDA approvals and the manufacturing process is transferred from Jazz Pharmaceuticals’ current supplier.

Dr. Walter Kittl, Senior Vice President and General Manager of Siegfried (USA) Inc., states “sodium oxybate provides an excellent fit with our expertise in the manufacturing of controlled substances and our proven capacity to perform exclusive synthesis. We are excited to work together with Jazz Pharmaceuticals to secure the supply chain of this important drug”.

Sodium oxybate is the sodium salt form of gamma-hydroxybutyrate, an endogenous neurotransmitter and metabolite of GABA. Sodium oxybate is the active ingredient in XYREM® (sodium oxybate) oral solution, approved by the FDA and marketed by Jazz Pharmaceuticals in the U.S. for the treatment of excessive daytime sleepiness and cataplexy (the sudden loss of muscle tone) in adult patients with narcolepsy.

Zofingen/Switzerland, Pennsville/U.S.A., May 28, 2010

For further information:

Marianne Späne, Head Business Development & Sales

Tel. +41 (0)62 746 15 20, Fax +41(0)62 746 12 02

Siegfried Ltd

Untere Brühlstrasse 4

CH – 4800 Zofingen

Walter Kittl, General Manager Siegfried (USA), Inc.

Tel. +1 877 763 8821, Fax +1 856 678 8201

Siegfried (USA), Inc.

33 Industrial Park Road

Pennsville, NJ 08070

About Siegfried (USA) Inc.

Siegfried (USA) Inc. is a wholly owned subsidiary of the Siegfried Group. The Siegfried Group is an international manufacturer of pharmaceutical products with production facilities located in the U.S.A., Switzerland, Germany and Malta. Siegfried currently has approximately 850 employees and achieved annual sales of approx. CHF 283 million in 2009.

Siegfried is active in both the primary and secondary production of drugs. The company develops and manufactures active pharmaceutical ingredients for the research-based pharmaceutical industry as well as the corresponding intermediate steps and standard products, and provides development and production services for drugs in finished dosage forms.

Siegfried Holding AG is listed on the Swiss Stock Exchange in Zurich (SWX: SFZN).

About Jazz Pharmaceuticals Inc.

Jazz Pharmaceuticals (Nasdaq: JAZZ) is a specialty pharmaceutical company that identifies, develops and commercializes innovative treatments for important, underserved markets in neurology and psychiatry. For further information see www.JazzPharmaceuticals.com.