Brand Name: Plegridy (Pen)
Generic Name: peginterferon beta-1a

Medication Class: Interferon beta
Similar Drugs: Avonex, Rebif
Manufacturer: Biogen Idec
FDA Approval Date:  August 2014

What is Plegridy and how does it work?

Plegridy (peginterferon beta-1a) is a subcutaneous injection that is used in people with relapsing multiple sclerosis (MS). It is human interferon manufactured using DNA technology. Its exact mechanism of action in treating multiple sclerosis is not fully known. Interferons are produced by cells that are part of the immune system. Interferons help the immune system fight cancer, viruses, bacteria, and other harmful substances. 

Plegridy is a pegylated interferon beta. Pegylation is the addition of polyethylene glycol to interferon, slowing its clearance from the body and preventing its degradation by various enzymes. Pegylation increases how long interferon remains in the body. Compared to once weekly dosing of non-pegylated interferon beta-1a drugs (Avonex and Rebif) used for relapsing MS, Plegridy is given once every two weeks.

What does Plegridy treat?

Plegridy is used for the treatment of relapsing multiple sclerosis. Patients with Relapsing forms of multiple sclerosis alternate between temporary improvement and worsening states of the disease.

How well does Plegridy work?

1012 patients with multiple sclerosis were studied for 1 year. Patients received Plegridy 125 micrograms or placebo every 14 days. Clinical and MRI outcomes were assessed at 48 weeks.

Compared to the placebo group patients receiving Plegridy 125 micrograms had:

36% reduction in the annual relapse rate

39% risk reduction in the number of patients with relapses

38% reduction in the risk of sustained disability progression

86% relative reduction in the number of gadolinium enhancing lesions

67% relative reduction in the number of new or enlarging T2 lesions

Interesting Facts about Plegridy

• Plegridy is the first pegylated beta interferon that is approved for the treatment of relapsing multiple Sclerosis.
• Plegridy can be self-administered and is available as a prefilled pen or a prefilled syringe.

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