Oral lipoic acid as a treatment for acute optic neuritis: a blinded, placebo controlled randomized trial

Abstract

Background: Lipoic acid, an antioxidant, has beneficial effects in experimental acute optic neuritis and autoimmune encephalomyelitis. Optical coherence tomography can detect retinal nerve fiber layer thinning, representing axonal degeneration, approximately 3-6 months after acute optic neuritis. Objective: To determine whether lipoic acid is neuroprotective in acute optic neuritis. Methods: A single-center, double-blind, randomized, placebo controlled, 24-week trial. Intervention included 6 weeks of once daily lipoic acid (1200 mg) or placebo within 14 days of acute optic neuritis diagnosis. The primary outcome was the mean difference in affected eye retinal nerve fiber layer (RNFL) thickness from baseline to 24 weeks. Results: We enrolled 31 subjects (placebo n¼16; lipoic acid n¼15; average age 38.6 years (standard deviation (SD) 10.3)). Affected eye mean global RNFL thickness (mm) in the lipoic acid group decreased from 108.47 (SD 26.11) at baseline to 79.31 (SD 19.26) at 24 weeks. The affected eye RNFL in the placebo group decreased from 103.67 (SD 18.04) at baseline to 84.43 (SD 20.94) at 24 weeks. Unaffected eye RNFL thickness did not significantly change in either group over 24 weeks. Conclusion: Six weeks of oral lipoic acid supplementation after acute optic neuritis is safe and well tolerated; however, because of insufficient recruitment, we could not conclude that lipoic acid treatment was neuroprotective in acute optic neuritis.

Evaluation of Dissolution Profiles of a Newly Developed Solid Oral Immediate-Release Formula Containing Alpha-Lipoic Acid

“…Diminishing the retinal nerve fiber layer as detected by optical coherence tomography (OCT) occurs 3-6 months following acute optic neuritis (AON), indicating retinal nerve ganglion cells axonal degeneration. Simultaneously, corticosteroids speed AON recovery, neuroprotective therapies for AON are lacking [41].…”

Failed, Interrupted, or Inconclusive Trials on Neuroprotective and Neuroregenerative Treatment Strategies in Multiple Sclerosis: Update 2015–2020

“…The results from the reviewed study need to be interpreted with caution due to the small number of participants and the short follow-up period [53]. Nevertheless, the disenchanting outcome of this trial is contrary to the promising pre-clinical results.…”

“…Completed in 2016, a double-blind, placebo-controlled, randomised Phase I trial analysed the effects of LA in 31 patients diagnosed with experimental AON [53]. Treatment with 1200 mg/day LA or placebo was initiated within 14 days after diagnosis and lasted 6 weeks, followed by an 18-week observation period.…”

“…Therefore, LA treatment in AON might only be suitable when administered immediately after symptom onset. Unfortunately, data on the mean duration to the first LA dose are not given in the reviewed trial [53].…”

Safety Evaluation of α-Lipoic Acid Supplementation: A Systematic Review and Meta-Analysis of Randomized Placebo-Controlled Clinical Studies

“…Additional 139 papers were excluded due to being pre-print papers ( n = 2), study protocols ( n = 6), reporting data from studies lacking of an appropriate placebo-controlled design for the supplementation ( n = 64), lacking of randomisation ( n = 5), testing the acute effect of ALA supplementation ( n = 7), testing ALA supplementation combined in nutraceutical compounds ( n = 27), testing intravenous treatment with ALA ( n = 11), testing topical treatment with ALA ( n = 4), lacking sufficient information about the nature of the adverse events ( n = 9), or reporting data overlapped with other publications ( n = 4) ( Supplementary file B ). Finally, 71 studies were eligible and included in the systematic review [ 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 ,…”