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May 1995

Levorotatory Form of 5-Hydroxytryptophan in Friedreich's Ataxia: Results of a Double-blind Drug-Placebo Cooperative Study

Author Affiliations

From the Ataxia Research Center and Cerebrovascular Unit, Hôpital Neurologique, Lyons (Dr Trouillas), Clinique Neurologique, Hôpital de la Timone Marseille (Dr Serratrice), Clinique des Maladies du Système Nerveux, Hôpital de la Salpétrière, Paris, (Dr Laplane), Clinique Neurologique, Hôpital Purpan, Toulouse (Drs Rascol and Clanet), Services de Neurologie, Hospices de Civies de Strasbourg (Dr Warter), Hôpital de Bellevue, Saint-Etienne (Dr Michel), Hôpital Saint-Joseph, Paris (Dr Degos), Hôpital Charles Nicolle, Rouen (Dr Augustin), Hôpital de Saint-Julien, Nancy (Dr Barroche), Clinique Neurologique, Hôpital Général, Dijon (Dr Dumas), Service de Neurologie, Hôpital d'Aix en Provence (Dr Viallet), Service de Neurologie, Hôpital de Pasteur (Dr Desnuelle), Biostatistical Unit, Faculté Alexis Carrel, Claude Bernard University, Lyons (Dr Adeleine), France.

Arch Neurol. 1995;52(5):456-460. doi:10.1001/archneur.1995.00540290042016

Objective:  To study the effect of the levorotatory form of 5-hydroxytryptophan on the cerebellar symptoms of Friedreich's ataxia.

Design:  Cooperative double-blind study of the levorotatory form of 5-hydroxytryptophan vs placebo.

Setting:  Twelve centers in research hospitals. Patients: Twenty-six patients were included; 19 completed the study (mean±SD age of patients, 25.9±8.1 years). Of these 19 patients, eight were treated with placebo and 11 were treated with the drug.

Main Outcome Measures:  A semiquantitative scale for kinetic and static ("postural") cerebellar functions and quantitative measurements of time in standard tests that evaluated stance, speech, writing, and drawing.

Results:  In the active treatment group, a significant decrease of the kinetic score was observed (P=.03), indicating an improvement in coordination.

Conclusions:  These results demonstrated that the levorotatory form of 5-hydroxytryptophan is able to modify significantly the cerebellar symptoms in patients with Friedreich's ataxia. However, the effect is only partial and not clinically major.