Tolerability and efficacy of L-acetylcarnitine in patients with peripheral neuropathies: a short-term, open multicentre study.

A total of 1097 patients, mean age 53.8 +/- 15 years, with peripheral mono-, multi- or polyneuropathy of various aetiologies, were enrolled in a multicentre, open-label, noncomparative, prospective clinical trial to evaluate the short-term tolerability and efficacy of L-acetylcarnitine (LAC). The drug was administered intramuscularly at a dosage of 1000 mg/day for the first 10 days, then orally at a dosage of 2000 mg/day for a further 20 days. Standard laboratory tests were used to evaluate safety and tolerability. Treatment efficacy was assessed clinically in the whole population, and in a subgroup of patients with 'lower than normal' baseline nerve conduction velocities (CVs), neurophysiological investigations were also performed at the end of the treatment period. After 30 days' therapy, there were no changes in vital signs or in blood tests. Only 18 patients reported poor tolerability of the treatment, mainly because of gastrointestinal events, and only 6 withdrew from the study because of these adverse events. The general and local (i.e. injection site) tolerability of LAC was rated highly by both patients and investigators. Neurological examination revealed that a significant percentage of patients with altered indices at baseline had normal indices by the end of the treatment period. The percentage of normalised patients varied from 11.9% for muscular trophism to 29.1% for the topographic score according to the different parameters taken into account in the neurological examination. Disease was rated as improved by 83.1% of investigators and 84.2% of patients. In patients with reduced CVs, significant increments were also recorded for motor and sensory nerves. This study demonstrates that LAC is well tolerated when given either intramuscularly or orally. The beneficial effects of short-term therapy in subjects with peripheral mono-, multi- or polyneuropathy should be confirmed by long-term studies.