Hospital Management

FDA grants breakthrough status to Biogen’s litifilimab for CLE

The Phase III AMETHYST study is currently assessing litifilimab’s safety and efficacy, with results anticipated in 2027.

The US Food and Drug Administration (FDA) has granted breakthrough therapy designation to Biogen’s litifilimab (BIIB059) for cutaneous lupus erythematosus (CLE), a chronic autoimmune skin condition.

This designation aims to expedite the development and review of medicines for serious conditions.

The FDA based its decision on comprehensive data, including findings from the Phase II LILAC study. Results from this trial indicated that litifilimab reduced skin disease activity in patients with CLE compared to placebo.

Currently, treatment for CLE relies on antimalarials, immunosuppressants and topical steroids. While these therapies alleviate symptoms, they do not modify disease progression.

The Phase III AMETHYST study is currently assessing litifilimab’s safety and efficacy, with results anticipated in 2027.

Discovered and developed by Biogen scientists, litifilimab is a humanised immunoglobulin G1 (IgG1) monoclonal antibody that targets blood dendritic cell antigen 2 (BDCA2). It is being investigated for both CLE and systemic lupus erythematosus (SLE).

Litifilimab remains an investigational product pending regulatory approval, with efficacy and safety yet to be established.

Biogen development executive vice-president and head Priya Singhal said: “The FDA grants breakthrough therapy designation to programmes based on the seriousness of the condition and the potential of the therapeutic candidate to provide substantial improvements over available therapies.

“The FDA's designation reinforces Biogen’s belief that litifilimab could be a first-in-class therapy targeting BDCA2 for cutaneous lupus erythematosus. This designation is a significant milestone for litifilimab as we advance the ongoing AMETHYST Phase III study, with the goal of bringing a new potential therapeutic option to the millions of people living with CLE.”

In December 2025, Biogen received a notice of compliance (NOC) from Health Canada for Zurzuvae (zuranolone), a neuroactive steroid (NAS), as a treatment for moderate or severe postpartum depression (PPD) in women.