Abstract
Objective: To assess the efficacy and tolerability of acetyl-L-carnitine (levacecarnine; LAC) versus placebo in the treatment of diabetic neuropathy, mainly by evaluating the effects of treatment on electrophysiological parameters and pain symptoms.
Design: This was a multicentre (n = 20), randomised, double-blind, placebo-controlled, parallel-group study.
Patients: 333 patients meeting clinical and/or neurophysiological criteria for diabetic neuropathy were enrolled.
Interventions: Patients were randomised to treatment with LAC or placebo. LAC (or placebo) was started intramuscularly at a dosage of 1000 mg/day for 10 days and continued orally at a dosage of 2000 mg/day for the remainder of the study (355 days).
Main outcome parameters and results: The main efficacy parameter was the effect of treatment on 6- and 12-month changes from baseline in nerve conduction velocity (NCV) and amplitude in the sensory (ulnar, sural and median) and motor (median, ulnar and peroneal) nerves. The effect of treatment on pain was also evaluated by means of a visual analogue scale (VAS). Among the 294 patients with impaired electrophysiological parameters at baseline, those treated with LAC showed a statistically significant improvement in mean NCV and amplitude compared with placebo (p < 0.01). The greatest changes in NCV (at 12 months) were observed in the sensory sural nerve (+5.7 m/sec in the LAC group vs +1.0 m/sec in the placebo group), sensory ulnar nerve (+2.9 vs +0.1 m/sec, respectively) and motor peroneal nerve (+2.7 vs −0.2 m/sec), whereas the greatest changes in amplitude were recorded in the motor peroneal nerve (+2.2 vs +0.1 mV). After 12 months of treatment, mean VAS scores for pain were significantly reduced from baseline by 39% in LAC-treated patients (p < 0.0 vs baseline) compared with 8% in placebo recipients. LAC was well tolerated over the study period.
Conclusions: LAC was effective and well tolerated in improving neurophysiological parameters and in reducing pain over a 1-year period. LAC is, therefore, a promising treatment option in patients with diabetic neuropathy.




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References
Pirart J. Diabetes mellitus and its degenerative complications: a prospective study of 4,400 patients observed between 1947 and 1973. Diabetes Care 1978; 1: 168–88 & 252–63
Deerochanawong C, Home PD, Alberti KGMM. A survey of lower limb amputation in diabetic patients. Diabet Med 1992; 9: 942–6
Morst RS, Sinnock P. The epidemiology of lower extremity amputation in diabetic individuals. Diabetes Care 1983; 6: 87–91
Theriault M, Dort J, Sutherland G, et al. A prospective quantitative study of sensory deficits after whole sural nerve biopsies in diabetic and nondiabetic patients: surgical approach and the role of collateral sprouting. Neurology 1998; 50: 480–4
Thomas PK, Brown MJ. Diabetic polyneuropathy. In: Dyck PJ, Asbury AK, Winegrad AI, et al., editors. Diabetic neuropathy. Philadelphia (PA): WB Saunders, 1987: 56–65
Greene DA, Stevens MJ, Feldman EL. Diabetic neuropathy: scope of the syndrome. Am J Med 1999; 107 (2B): S2–8
Dyck PJ, Zimmerman BR, Vilen TH, et al. Nerve glucose, fructose, sorbitol, myo-inositol, and fiber degeneration and regeneration in diabetic polyneuropathy. N Engl J Med 1988; 319: 542–8
Stevens MJ, Feldman EL, Greene DA. The aetiology of diabetic neuropathy: the combined roles of metabolic and vascular defects. Diabet Med 1995; 12: 566–79
Tomlinson DR, Stevens EJ, Diemel LT. Aldose reductase inhibitors and their potential for the treatment of diabetic complications. Trends Pharmacol Sci 1994; 15: 293–7
Dyck PJ. Hypoxic neuropathy: does hypoxia play a role in diabetic neuropathy? Neuropathy 1989; 39: 111–8
Jamal GA. Pathogenesis of diabetic neuropathy: the role of the n-6 essential fatty acids and their eicosanoid derivations. Diabet Med 1990; 7: 574–9
Giugliano D, Ceriello A, Paolisso G. Oxidative stress and diabetic vascular complications. Diabetes Care 1996; 19: 257–67
Thomas PK. Growth factors and diabetic neuropathy. Diabet Med 1994; 11: 732–9
Faradji V, Sotelo J. Low serum levels of nerve growth factor in diabetic neuropathy. Acta Neurol Scand 1990; 81: 402–6
Markesbery WR, McQuillen MP, Procopis PG, et al. Muscle carnitine deficiency: association with lipid myopathy, vacuolar neuropathy and vacuolated leucocytes. Arch Neurol 1974; 31: 320–4
De Simone R, Ramacci MT, Aloe L. Effect of acetyl-l-carnitine on forebrain cholinergic neurons of developing rats. Int J Dev Neurosci 1991; 9: 39–46
Rampello L, Giammona G, Aleppo MG, et al. Trophic action of acetyl-L-carnitine in neuronal cultures. Acta Neurol 1992; 14: 15–21
Gorio A, Di Giulio AM, Tenconi B, et al. Peptide alterations in autonomic diabetic neuropathy prevented by acetyl-L-carnitine. Int J Clin Pharmacol Res 1992; 12: 225–30
Tesco G, Latorraca S, Piersanti P, et al. Protection from oxygen radical damage in human diploid fibroblasts by acetyl-L-carnitine. Dementia 1992; 3: 58–60
Arienti G, Ramacci MT, Maccari F, et al. Acetyl-L-carnitine influences the fluidity of brain microsomes and of liposomes made of rat brain microsomal lipid extracts. Neurochem Res 1992; 17: 671–5
Ido Y, McHowatt J, Chang KC, et al. Neuronal dysfunction and metabolic imbalances in diabetic rats: prevention by acetyl-L-carnitine. Diabetes 1994; 43: 1469–77
De Grandis D, Santoro L, Di Benedetto P. L-Acetylcarnitine in the treatment of patients with peripheral neuropathies: a short-term, double-blind, clinical study of 426 patients. Clin Drug Invest 1995; 10: 317–22
De Grandis D. Tolerability and efficacy of L-acetylcarnitine in patients with peripheral neuropathies: a short-term, open multicentre study. Clin Drug Invest 1998; 15: 73–9
Quatraro A, Roca P, Donzella P, et al. Acetyl-L-carnitine for symptomatic diabetic neuropathy [letter]. Diabetologia 1995; 38: 123
Feldman EL, Stevens MJ, Thomas PK, et al. A practical twostep quantitative clinical and electrophysiological assessment for the diagnosis and staging of diabetic neuropathy. Diabetes Care 1994; 17: 1281–9
Proceedings of a Consensus Development Conference on Standardized Measures in Diabetic Neuropathy. Neurology 1992; 42: 1823–39
Kimura J. Electrodiagnosis in diseases of nerve and muscle: principles and practice. 3rd ed. Oxford: Oxford University Press, 2001
Scott J, Huskisson EC. Graphic representation of pain. Pain 1976; 2: 175–84
The DCCT Research Group. The effect of intensive diabetes therapy on the development and progression of neuropathy. Ann Intern Med 1995; 122: 561–8
Gaster B, Hirsch I. The effects of improved glycemic control on complications in type 2 diabetes. Arch Intern Med 1998; 158: 134–40
Herman WH. Clinical evidence: glycaemic control in diabetes. BMJ 1999; 319 (7202): 104–6
Greene DA, Arezzo JC, Brown MB, et al. Effect of aldose reductase inhibition on nerve conduction and morphometry in diabetic neuropathy. Neurology 1999; 53: 580–91
Hotta N, Toyota T, Matsuoka K, et al. Clinical efficacy of fidarestat, a novel aldose reductase inhibitor, for diabetic peripheral neuropathy: a 52-week multicenter placebo-controlled double-blind parallel group study. Diabetes Care 2001; 24: 1776–82
Apfel SC, Kessler JA, Adornato BT, et al., for NGF Study Group. Recombinant human nerve growth factor in the treatment of diabetic polyneuropathy. Neurology 1998; 51: 695–702
Horrobin DF. Gamma-linolenic acid in the treatment of diabetic neuropathy. In: Bolton AJM, editor. Diabetic neuropathy. Carnforth, UK: Marius Press, 1997
Malik RA, Williamson S, Abbott CA, et al. Effect of angiotensin-converting enzyme (ACE) inhibitor trandolapril on human diabetic neuropathy: randomised double-blind controlled trial. Lancet 1998; 352: 1978–81
Jensen PG, Larson JR. Management of painful diabetic neuropathy. Drugs Aging 2001; 18: 737–49
Dyck PJ, Karnes JL, Daube J, et al. Clinical and neuropathological criteria for the diagnosis and staging of diabetic polyneuropathy. Brain 1985; 108: 861–80
Dyck PJ, Karnes JL, O’Brien PC, et al. The Rochester Diabetic Neuropathy Study: reassessment of tests and criteria for diagnosis and staged severity. Neurology 1992; 42: 1164–70
Arezzo JC. The use of electrophysiology for the assessment of diabetic neuropathy. Neurosci Res Commun 1997; 21: 13–23
De Grandis D. Long-term treatment with L-acetylcarnitine in diabetic polyneuropathy [abstract]. J Neurol Sci 1997; 150 (Suppl.): 1–42–08
Dyck PJ, O’Brien PC. Meaningful degrees of prevention or improvement of nerve conduction in controlled clinical trials of diabetic neuropathy. Diabetes Care 1989; 12: 649–52
Acknowledgements
This study was funded by Sigma-Tau, Italy.
LAC in Diabetic Neuropathy Study Group (Italy): Prof. F. Angeleri (Università degli Studi, Ancona), Prof. R. Badino (Ospedale S. Corona, Pietra Ligure), Dr F. Bellavere (Ospedale Civile, Padova), Prof. G. Cazzato (Ospedale Cattinara, Trieste), Dr C.A. De Fanti (Ospedali Riuniti, Bergamo), Prof. T. Di Perri (Università degli Studi, Siena), Dr F. Galeone (Ospedale Civile, Pescia), Dr A. Giustina (Università degli Studi, Brescia), Prof. R. Lucchi (Ospedale Estense, Modena), Dr M. Mantero (Ospedale Civile, Savona), Prof. C. Morocutti (Policlinico Umberto I, Roma), Dr C. Noacco (Ospedale Civile, Udine), Dr F. Orio (Ospedale Civile, Eboli), Dr A. Parente (Ospedali Riuniti, Foggia), Prof. F. Piccoli (Università degli Studi, Palermo), Dr I. Sacco (Ospedale S. Carlo), Dr P. Simone (Ospedale Casa Sollievo della Sofferenza, S. Giovanni Rotondo, Foggia), Dr C. Teodonio (Ospedale S. Giovanni-Addolorata, Roma), Dr A. Venezia (Ospedali Riuniti, Matera), Prof. D. Zerbi (Ospedale S. Carlo Borromeo, Milano).
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De Grandis, D., Minardi, C. Acetyl-L-Carnitine (Levacecarnine) in the Treatment of Diabetic Neuropathy. Drugs R&D 3, 223–231 (2002). https://doi.org/10.2165/00126839-200203040-00001
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DOI: https://doi.org/10.2165/00126839-200203040-00001