Ibudilast works by suppressing three cell signaling molecules that promote inflammation: IL-1β, TNF-α, and IL-6. Ibudilast may also upregulate anti-inflammatory cell signaling molecules resulting in neuroprotective effects and reduced neuroinflammation. Ibudilast has been approved in Japan and Korea to treat asthma and cerebrovascular disorder for over 20 years.
Phase II Trial- Relapsing-Remitting MS (RRMS)
A multicenter, double-blind, placebo-controlled phase II trial recruited 297 people with RRMS. Participants were randomized to receive ibudilast (30 or 60 mg /day) or placebo for 12 months. Treatment with ibudilast had no effect of the treatment on the number of active lesions or relapse rate. There may be a neuroprotective effect as fewer people witnessed confirmed disease progression and displayed reduced brain atrophy.
SPRINT MS: Phase II Trial
a phase II randomized, double-blind, placebo-controlled,
multicenter clinical trial tested the efficacy and safety of
ibudilast in 255 people with PPMS and SPMS. Study participants
received either ibudilast twice daily for a total dose of
100mg, or placebo over the course of two years. Those in the
ibudilast group had a 48% reduction in brain atrophy as
compared with placebo. Ibudilast also met its second primary
outcome of safety and tolerability. A larger phase III trial is
required to fully test the effectiveness of ibudilast in
The adverse effects reported from the SPRINT-MS trial included gastrointestinal issues, such as nausea, diarrhea, and abdominal pain. Other adverse events reported include depression and fatigue.
Barkhof f et al. Ibudilast in relapsing-remitting multiple sclerosis: a neuroprotectant? Neurology. 2010; 74(13):1033-40