Biogen Idec announced top-line results from the Phase 2 acute optic neuritis (AON) RENEW trial in which treatment with anti-LINGO-1 showed evidence of biological repair of the visual system. Anti-LINGO-1 demonstrated an improvement in the study's primary endpoint, recovery of optic nerve latency (time for a signal to travel from the retina to the visual cortex), as measured by full field visual evoked potential (FF-VEP), relative to placebo. The study showed no effect on secondary endpoints, including change in thickness of the retinal layers (optic nerve neurons and axons) and visual function, as measured by spectral domain optical coherence tomography (SD-OCT) and low contrast letter acuity, respectively.

AON damages the optic nerve, causing loss of the myelin sheath and axonal injury, and may result in loss of visual function. AON is considered a good clinical model to measure the hypothesized mechanisms of action of anti-LINGO-1, remyelination and neuroprotection. RENEW was designed to study anti-LINGO-1's ability to enable repair of an optic nerve lesion via axonal remyelination following the onset of a first episode of AON.

RENEW is part of the anti-LINGO-1 Phase 2 clinical development program, which includes the SYNERGY trial in multiple sclerosis. RENEW studied the effects on remyelination by measuring the latency of nerve conduction between the retina and the visual cortex in the brain using FF-VEP. The primary endpoint measured FF-VEP latency for the affected eye at week 24 compared to the unaffected fellow eye at baseline.

Results demonstrated a 34% improvement (p=0.0504) in the recovery of optic nerve latency compared to placebo in the per-protocol population. The analysis of the intent-to-treat (ITT) population, which includes patients in both arms who did not complete the study, showed a positive trend but did not reach statistical significance. Anti-LINGO-1 was generally well tolerated.

The overall incidence and severity of adverse events (AEs) was comparable across treatment arms. Treatment-related anti-LINGO-1 serious adverse events (SAEs) consisted of two patients with hypersensitivity reactions occurring around the time of infusion and one patient with an asymptomatic elevation in liver transaminases which resolved after drug discontinuation. No deaths occurred during the trial. No immunogenicity was observed.