Commentary
Video
Author(s):
The head of Biogen’s MS and Immunology Department Unit detailed the potential of combination approaches to treat MS, including the reasons for diroximel fumarate in the newly initiated phase 2 FUSION study. [WATCH TIME: 3 minutes]
WATCH TIME: 3 minutes
"I don’t think MS compared to other therapeutic areas is typically a combination work, but rather switch and sequential. But it’s probably worth thinking about. For certain patients, maybe 2 discrete mechanisms of action may be able to push through and get higher efficacy."
There are several promising Bruton’s tyrosine kinase (BTK) inhibitors in development for the treatment of multiple sclerosis (MS), including BIIB091 (Biogen), which is comprised of a highly selective, reversible, non-covalent mechanism of action. At MSMilan 2023, the joint ECTRIMS-ACTRIMS meeting, held October 11-13, in Milan, Italy, investigators presented trial design details for the phase 2 FUSION study (NCT05798520), a 2-part, randomized, active-controlled trial assessing the efficacy and safety of BIIB091.
The study, which plans to enroll 125 patients with relapsing MS in Part 1, and 150 in Part 2, will assess BIIB091 as both a monotherapy and in combination with diroximel fumarate (Vumerity; Biogen), a previously approved disease-modifying therapy for relapsing MS. Diroximel fumarate, which has been on the market for several years, is designed to modulate the Nrf2 pathway and the proinflammatory properties of peripheral immune cells, including T-cells and myeloid cells.
Both parts of the study are 48 weeks, consisting of a 16-week double-blind period, with an interim analysis after all participants reach week 16, followed by 32-week blinded period. Part 1 consists of 3 arms: high-dose BIIB091, low-dose BIIB091, and standard-dose diroximel fumarate. Part 2 of the study consists of 3 arms: selected-dose BIIB091 with standard diroximel fumarate, selected-dose BIIB091 with low-dose diroximel fumarate, and standard-dose diroximel fumarate.
In an interview with NeurologyLive®, Diana Gallagher, MD, head of Biogen’s MS and Immunology Department Unit, discussed the reasons behind the use of diroximel fumarate and the potential of combination therapeutic approaches. In addition, she shared her thoughts on the significance of the study if successful, and what BTK inhibitors add to the ever-expanding MS treatment paradigm.