US patients with multiple sclerosis could soon gain access to a new treatment option after the US Food and Drug Administration approved Biogen and AbbVie's once-monthly, self-administered subcutaneous injection Zinbryta.

Zinbryta (daclizumab) has been cleared for use to treat relapsing forms of the chronic, inflammatory disease, but only in patients who have had an inadequate response to two or more MS drugs because, because it has serious safety risks.

The green light is based on data from two pivotal trials, DECIDE and SELECT, in which the drug was dosed subcutaneously every four weeks in patients, showing a statistically-significant reduction in the annual relapse rate of MS.

In the DECIDE trial, this reduction was 45% compared with Biogen's MS therapy Avonex (interferon beta-1a), while in the SELECT study it was 54% versus placebo.

Because of the safety risks, Zinbryta has a boxed warning and is available only through a restricted distribution program under a Risk Evaluation and Mitigation Strategy.

The boxed warning informs prescribers that the drug can cause severe liver injury, including life-threatening and fatal events, and also highlights other important risks of treatment including immune conditions, such as inflammation of the colon, skin reactions, and enlargement of lymph nodes.

Additional highlighted warnings include hypersensitivity reactions (anaphylaxis or angioedema), increased risk of infections, and symptoms of depression and/or suicidal ideation.

"MS affects each person differently, so it is critical that people have additional therapeutic options to address their needs throughout the course of the disease," said Jeffrey English, director of clinical research, Multiple Sclerosis Center of Atlanta. "Zinbryta provides a meaningful new treatment option that demonstrates efficacy and offers once-monthly dosing."

Zinbryta has also been recommended for approval in Europe.