Three beta interferons are widely used in the treatment of patients with relapsing-remitting multiple sclerosis (RRMS).

Glatiramer acetate (Copaxone - Teva Marion Partners), formerly known as copolymer-l, has been approved by the US Food and Drug Administration (FDA) for treatment of relapsing-remitting multiple sclerosis (MS). Interferon β-1b (Betaseron) and interferon β-1a (Avonex - Medical Letter, 38:63, 1996) were previously approved for this indication.

Natalizumab, a recombinant humanized monoclonal antibody, has received accelerated approval from the FDA for intravenous treatment of relapsing forms of multiple sclerosis (MS). The beta interferons and glatiramer acetate are widely used for treatment of MS; they generally reduce the number of relapses by about 30% compared to placebo, and have been shown to be safe and effective for periods ranging from 4 to 10 years.

The FDA has approved a new interferon beta-1b product (Extavia – Novartis) for treatment of relapsing forms of multiple sclerosis (MS). Extavia is identical to Betaseron (Bayer); both are produced in the same factory and packaged separately.

Interferon β-1a (Avonex - Biogen), a recombinant form of human interferon β, has been approved by the US Food and Drug Administration (FDA) for treatment of relapsing forms of multiple sclerosis (MS). Interferon β-1a (Betaseron - Berlex), a recombinant analog of interferon β that differs from interferon β-1a in having a serine substituted for a cysteine and in not being glycosylated, was previously approved for this indication (Medical Letter, 35:61, 1993; BW van Oosten et al, Drugs, 49:200, 1995).

The FDA has approved a pegylated form of interferon beta-1a (Plegridy – Biogen) for biweekly treatment of patients with relapsing multiple sclerosis (MS).

The FDA has approved daclizumab (Zinbryta – Biogen/Abbvie), an interleukin-2 (IL-2) receptor blocking monoclonal antibody, for treatment of adults with relapsing forms of multiple sclerosis (MS). It is the first subcutaneously injected monoclonal antibody to be approved for treatment of MS.

When patents expire on brand-name drugs and generic formulations become available, patients and managed care organizations may express a preference for the lower-cost generics. Are they equivalent to the brand-name product?

The FDA has approved the marketing of fingolimod (Gilenya – Novartis) to reduce the frequency of clinical exacerbations and delay the accumulation of physical disability in patients with relapsing forms of multiple sclerosis (MS). Fingolimod is the first oral drug approved for this indication.

The FDA has approved dimethyl fumarate (Tecfidera – Biogen Idec), formerly called BG-12, for treatment of relapsing forms of multiple sclerosis (MS). It is the third oral drug to be approved in recent years for this indication.