Intramuscular Injection Form of Peginterferon Beta-1a Approved for Use in Treating Relapsing Multiple Sclerosis

March 2021

In February 2021, the US Food and Drug Administration (FDA) approved a new intramuscular (IM) injection route of administration for Plegridy (peginterferon beta-1a) for the treatment of relapsing forms of multiple sclerosis (MS). The new IM injection route will provide patients with relapsing MS a treatment option with the potential for significantly reduced injection-site reactions.

The FDA approved Plegridy IM based on results from a phase 1 study that evaluated the bioequivalence of IM and subcutaneous (SC) peginterferon beta-1a in healthy volunteers. The study also evaluated adverse reactions associated with IM administration compared with SC administration. The study results confirmed the 2 dosing regimens were bioequivalent. Participants who received Plegridy IM experienced fewer injection-site reactions compared with participants who received SC administration (14.4% vs 32.1%). The overall safety profiles of IM and SC administration were generally similar, and there were no new safety signals observed.

The COVID-19 pandemic has severely disrupted the healthcare delivery systems in many countries, making issues of treatment access and availability all the more important to the 2.3 million people worldwide who have been diagnosed with MS.

In the news release announcing the approval of Plegridy IM, Maha Radhakrishnan, MD, Chief Medical Officer at Biogen, said the company is “committed to continued innovation to give people with MS more choices and more options to meet their individual preferences and needs.” She also said that this approval “gives new and current MS patients a different delivery method that has the potential to significantly reduce injection site reactions.”


Biogen. Biogen announces FDA approval of PLEGRIDY (peginterferon beta-1a) intramuscular administration for multiple sclerosis. Published February 1, 2021. Accessed March 1, 2021.

Related Items

Subscribe to Value-Based Care in Neurology

Stay up to date with the latest news in neurology by subscribing to receive the free VBCN e‑Newsletter.