Pivotal Studies

Rebif: A landmark treatment option for relapsing MS

These are promising times for people living with MS. Although there isn't a cure, Rebif^® (interferon beta-1a) has been shown to significantly impact the disease. Rebif is an effective treatment for reducing MRI lesions and area, preventing relapses, and slowing the progression of disability.

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

Rebif has been available in the United States since March 2002, when it was approved by the Food and Drug Administration (FDA). This was based on the 2-year results in the PRISMS* study and 24 week results from the EVIDENCE** study.

The approval of Rebif is historic because the product was granted the first-ever exception to the Orphan Drug Act (ODA) market exclusivity rule based on superior efficacy.

The ODA is a law that provides 7-year market exclusivity to a drug developed for a relatively rare disease, such as MS. Exceptions to this market exclusivity are made if another version of the same drug is proven to be safer or more effective.

In 1996, the FDA approved the use of Avonex^® (interferon beta-1a) in the United States. The FDA gave it market exclusivity through May 2003 based on the ODA. Because the makers of Rebif wanted FDA approval before then to give people living with relapsing MS more treatment options, they had to show Rebif was either safer or worked better than Avonex to overcome the exclusivity. In a head-to-head study, Rebif 44 mcg three times a week proved to work better than Avonex 30 mcg once a week at reducing the frequency of relapses. This was proven at 24 and 48 weeks. This effect was maintained through the completion of the study which was an average of 64 weeks.

The FDA granted Rebif the FIRST exception to the exclusivity rule based on efficacy.

EMD Serono and Pfizer: fighting MS head-on

In the United States, Rebif is brought to you by EMD Serono and Pfizer. EMD Serono and Pfizer are committed to ongoing research and development that supports new opportunities for future treatments in MS. Through research and innovation, EMD Serono and Pfizer will continue to fight MS.

The PRISMS* Study

— The PRISMS study is the largest placebo-controlled study of interferon beta-1a ever conducted in relapsing-remitting MS (RRMS) and proved that Rebif is an effective treatment at reducing relapses and delaying disease progression vs. placebo over two years.

• Rebif effectively reduced MRI lesion area and activity relative to placebo treatment
• Rebif effectively reduced relapses relative to placebo treatment
• Rebif effectively delayed disability progression relative to placebo treatment

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

Read about the PRISMS Study

The EVIDENCE** Study

— The EVIDENCE study demonstrated the superior effectiveness of a higher, more frequent subcutaneous interferon beta-1a dosing of Rebif 44 mcg tiw versus Avonex^® (interferon beta-1a) 30 mcg once a week (qw) at reducing relapses at 24 and 48 weeks. These results were seen in patients through the completion of the study — average 64 weeks.

• People taking Rebif 44 mcg tiw showed a significant reduction in MRI activity at 24 weeks, 48 and through the completion of the study at an average of 64 weeks
• People taking Rebif 44 mcg tiw were more likely to remain relapse-free than people treated with Avonex. This was shown at 24, 48, and through the completion of the study at an average of 64 weeks
• Side effects were generally similar in those treated with Rebif 44 mcg tiw compared to those treated with Avonex

People taking Rebif showed a significant reduction in relapses and MRI activity at 24 weeks, 48, and through the completion of the study which was an average of 64 weeks.

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

Learn more about ongoing clinical studies

Compared to Avonex, side effects were generally similar despite the higher, more frequent dosing of Rebif 44 mcg tiw with three exceptions. As to be expected with higher, more frequent dosing, people taking Rebif had a greater number of injection-site reactions (85% Rebif vs. 33% Avonex), liver disorders (18% Rebif vs. 10% Avonex), and white blood cell disorders (13.6% Rebif vs. 5.3% Avonex). However, the rate of discontinuation or serious adverse events was similar for the two drugs. Flu-like symptoms were significantly higher for people taking Avonex than for people taking Rebif (45% Rebif vs. 53% Avonex).

Read about the EVIDENCE study

Avonex is a registered trademark of Biogen Idec.