GENEVA, Switzerland, September 17 /PRNewswire/ -- Merck Serono, a division of Merck KGaA, Darmstadt, Germany, announced today that patient enrollment has been completed in the REFLEX trial (REbif FLEXible dosing in early multiple sclerosis). This randomized, double-blind, placebo-controlled, international Phase III trial is designed to evaluate the therapeutic benefit of Rebif(R) (interferon beta-1a) on the time to conversion to multiple sclerosis (MS) in people with a first clinical event suggestive of the disease.

"It has been demonstrated that treatment with interferon beta can reduce the risk of developing multiple sclerosis," said Anton Hoos, Executive Vice President, Global Development, Merck Serono. "However, additional research still needs to be conducted in this area and we believe the REFLEX study will provide valuable insights."

A total of 517 patients considered at risk of developing MS due to a recently experienced isolated demyelinating event (e.g. optic neuritis, myelopathy or brainstem syndrome) and having magnetic resonance imaging (MRI) brain scans consistent with early signs of MS have been enrolled in the REFLEX trial. Study participants were randomized in a 1:1:1 ratio to receive either Rebif(R) 44 micrograms three times a week, Rebif(R) 44 micrograms once a week, or placebo as a subcutaneous injection. Patients will be treated for a period of 24 months, or up to the time when they experience a second attack leading to a diagnosis of clinically definite MS. At this point, patients are offered open-label treatment with Rebif(R) 44 micrograms three times a week.

The primary endpoint of the REFLEX trial is time to conversion to MS, according to the McDonald criteria. Further endpoints include time to conversion to clinically definite MS (the main secondary endpoint), assessments of MRI brain scans, clinical relapses and disability progression.

Rebif(R) is currently approved for the treatment of relapsing forms of MS. It has been proven effective in all three key measures of treatment effectiveness: MRI lesion area and activity*, relapse rates and disability progression. The safety profile of Rebif(R) is supported by a robust, ongoing clinical development and post-marketing program and a 10-year record of use by MS patients.

The REFLEX trial is being conducted with the new formulation of Rebif(R). The new formulation of Rebif(R) was approved in the European Union in August 2007 and in Canada in September 2007 and is now marketed in all EU countries and in Canada. The new formulation of Rebif(R) is not available in the United States.

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

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 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 micrograms and 44 micrograms ready-to-use pre-filled syringe and a titration pack (8.8 micrograms).

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.

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

About Merck Serono and multiple sclerosis

Merck Serono is a leader in multiple sclerosis (MS) with Rebif(R) (interferon beta-1a), a disease-modifying drug used to treat relapsing forms of MS, which is registered in more than 80 countries worldwide. Full prescribing information for this product can be obtained by contacting the Company or visiting its website. Additional therapeutic options are currently under development at Merck Serono, including oral cladribine, currently in Phase III and potentially the first oral therapy for MS, as well as several products in early stage development. Merck Serono also is taking a leading role in developing an understanding of the role of genetics in MS.

About multiple sclerosis

Multiple sclerosis (MS) is a chronic, inflammatory condition of the nervous system and is the most common, non-traumatic, disabling 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), Euthyrox(R), Saizen(R), Serostim(R)), as well as psoriasis (Raptiva(R)).

With an annual R&D expenditure 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 31,946 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

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