GENEVA, Switzerland, June 10 /PRNewswire/ --

- A Decade Dedicated to Helping People With Multiple Sclerosis

- Extensive Research and Development Activities Underscore Long-Term Commitment to Improving the Lives of People With Multiple Sclerosis

Merck's Serono's Rebif(R) (interferon beta-1a) is celebrating its 10th anniversary this year. Since receiving approval for the treatment of relapsing-remitting multiple sclerosis (MS) 10 years ago in the European Union, as well as in Canada and Switzerland, Rebif(R) has become a foundation therapy for MS.

"The introduction of Rebif(R) was a significant advancement in the treatment of MS," said Elmar Schnee, President of Merck Serono. "We will continue our long-term commitment to improving the lives of people with MS through the development of additional therapeutic options."

In the pivotal trial that led to its approval - the PRISMS(1) study - Rebif(R) was the first MS treatment to be proven effective on all three key measures of treatment effectiveness: MRI lesion area and activity(2), relapse rates and disability progression. In 2002, Rebif(R) 44 mcg was approved in the United States under the terms of the Orphan Drug Act by demonstrating clinical superiority in terms of efficacy over Avonex(R) at 24 weeks in the EVIDENCE(3) head-to-head study. Rebif(R) is now available in more than 80 countries. The safety profile of Rebif(R) is supported by a robust, ongoing clinical development and post-marketing program and a patient exposure to the marketed product estimated at more than 500,000 patient-years to date.

Merck Serono is continuing to advance the treatment of MS with its research and development pipeline. The most advanced projects are cladribine tablets, currently in Phase III, and atacicept, currently in Phase II. With regulatory filing expected in 2009, cladribine tablets could potentially become the first oral therapy for MS.

Merck Serono is also taking a leading role in furthering the understanding of the role of genetics in MS. Genetics is used to identify disease-associated genes. The proteins encoded by these genes can be used either as targets for the development of compounds or directly as therapeutics to modulate or restore the proper physiological function. In addition, the knowledge of genetics in MS may provide a basis for development of safer and more effective drugs, and potentially treatments matched to groups of patients (patient stratification) by identifying their ability to respond to treatment.

"The understanding of the genetics of MS will contribute to a better understanding of the disease and of the pathways that are involved in the disease," said Bernhard Kirschbaum, Executive Vice President Research at Merck Serono. "We believe that our genetics research platform provides a solid basis for the discovery of the treatments of the future."

In October 2007, Merck Serono announced the identification of gene DPP6 at the 23rd Congress of the European Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS) in Prague, Czech Republic. Gene DPP6, which is highly expressed in the brain and spinal cord of patients with primary progressive MS, may play a key role in the development of this subtype of MS characterized by a steady progression of disability, without any obvious relapses and remissions, for which there is currently no approved therapy.

(1) PRISMS: Prevention of Relapses and disability by Interferon beta-1a Subcutaneously in MS

(2) The exact correlation between MRI findings and the current or future clinical status of patients, including disability progression, is unknown.

(3) EVIDENCE: EVidence for Interferon Dose-response European-North American Comparative Efficacy

Key milestones for Rebif(R) - February 1998: Approval of Rebif(R) 22 and 44 mcg in Canada - May 1998: Approval of Rebif(R) 22 mcg in the European Union - December 1998: Approval of Rebif(R) 22 and 44 mcg in Switzerland - April 1999: Approval of Rebif(R) 44 mcg in the European Union - March 2002: Approval of Rebif(R) 44 mcg in the United States - July 2002: Signature of agreement with Pfizer for the co-promotion of Rebif(R) in the US - 2004: Rebif(R) becomes a blockbuster with annual sales exceeding USD1bn - August 2007: Approval of new formulation of Rebif(R) - designed to improve injection tolerability - in the European Union - September 2007: Approval of new formulation of Rebif(R) in Canada

About Rebif(R)

Rebif(R) (interferon beta-1a) is a disease-modifying drug used to treat relapsing forms of multiple sclerosis (MS) and is similar to the interferon beta protein produced by the human body. The efficacy of Rebif(R) in chronic progressive MS has not been established. Interferons are thought to help modulate the body's immune system, fight disease and reduce inflammation. The exact mechanism is unknown.

Rebif(R), which was approved in Europe in 1998 and in the US in 2002, is registered in more than 80 countries worldwide. Rebif(R) has been proven to delay the progression of disability, reduce the frequency of relapses and reduce MRI lesion activity and area*. Rebif(R) is available in a 22 mcg and 44 mcg ready-to-use pre-filled syringe and a titration pack (8.8 mcg).

Rebif(R) should be used with caution in patients with a history of depression, liver disease and seizures. Most commonly reported side effects are flu-like symptoms, injection site disorders, elevation of liver enzymes and blood cell abnormalities. Patients, especially those with depression, seizure disorders, or liver problems, should discuss treatment with Rebif(R) with their doctors. For more information about Rebif(R), please visit http://www.mslifelines.com for prescribing information.

In the EVIDENCE Study (EVidence of Interferon Dose-response: European North American Comparative Efficacy), compared with Avonex(R), adverse events were similar, despite higher, more frequent dosing with Rebif(R). Exceptions included injection-site reactions, hepatic function disorders, and white blood cell disorders, which were more frequent with Rebif(R). Flu-like symptoms were more frequent with Avonex(R).

* The exact correlation between MRI findings and the current or future clinical status of patients, including disability progression, is unknown.

About multiple sclerosis

Multiple sclerosis (MS) is a chronic, inflammatory condition of the nervous system and is the most common, non-traumatic, neurological disease in young adults. The World Health Organization estimates that up to 2.5 million people suffer from MS worldwide. While symptoms can vary, the most common symptoms of MS include blurred vision, numbness or tingling in the limbs and problems with strength and coordination. The relapsing forms of MS are the most common.

About Merck Serono

Merck Serono is the division for innovative prescription pharmaceuticals of Merck, a global pharmaceutical and chemical group. Headquartered in Geneva, Switzerland, Merck Serono discovers, develops, manufactures and markets innovative small molecules and biopharmaceuticals to help patients with unmet medical needs. Its North American business operates in the United States and Canada as EMD Serono.

Merck Serono has leading brands serving patients with cancer (Erbitux(R)), multiple sclerosis (Rebif(R)), infertility (Gonal-f(R)), endocrine and cardiometabolic disorders (Glucophage(R), Concor(R), Saizen(R), Serostim(R)), as well as psoriasis (Raptiva(R)).

With an annual R&D investment of around EUR 1bn, Merck Serono is committed to growing its business in specialist-focused therapeutic areas including neurodegenerative diseases, oncology, fertility and endocrinology, as well as new areas potentially arising out of research and development in autoimmune and inflammatory diseases.

About Merck

Merck is a global pharmaceutical and chemical company with total revenues of EUR 7.1 billion in 2007, a history that began in 1668, and a future shaped by 31,681 employees in 60 countries. Its success is characterized by innovations from entrepreneurial employees. Merck's operating activities come under the umbrella of Merck KGaA, in which the Merck family holds an approximately 70% interest and free shareholders own the remaining approximately 30%. In 1917 the U.S. subsidiary Merck & Co. was expropriated and has been an independent company ever since.

For more information, please visit http://www.merckserono.net or http://www.merck.de

Merck Serono, 9 Chemin des Mines, 1202 Geneva, Switzerland, Media Relations, Tel: +41-22-414-36-00