A phase I study of aromatic L-amino acid decarboxylase gene therapy for Parkinson's disease.
Gene transfer of dopamine-synthesizing enzymes into the striatal neurons has led to behavioral recovery in animal models of Parkinson's disease (PD). We evaluated the safety, tolerability, and potential efficacy of adeno-associated virus (AAV) vector-mediated gene delivery of aromatic L-amino acid decarboxylase (AADC) into the putamen of PD patients. Six PD patients were evaluated at baseline and at 6 months, using multiple measures, including the Unified Parkinson's Disease Rating Scale (UPDRS), motor state diaries, and positron emission tomography (PET) with 6-[(18)F]fluoro-L-m-tyrosine (FMT), a tracer for AADC. The short-duration response to levodopa was measured in three patients. The procedure was well tolerated. Six months after surgery, motor functions in the OFF-medication state improved an average of 46% based on the UPDRS scores, without apparent changes in the short-duration response to levodopa. PET revealed a 56% increase in FMT activity, which persisted up to 96 weeks. Our findings provide class IV evidence regarding the safety and efficacy of AADC gene therapy and warrant further evaluation in a randomized, controlled, phase 2 setting.
Muramatsu
Shin-ichi
S
Division of Neurology, Department of Medicine, Jichi Medical University, Tochigi, Japan. muramats@jichi.ac.jp
Fujimoto
Ken-ichi
K
Kato
Seiya
S
Mizukami
Hiroaki
H
Asari
Sayaka
S
Ikeguchi
Kunihiko
K
Kawakami
Tadataka
T
Urabe
Masashi
M
Kume
Akihiro
A
Sato
Toshihiko
T
Watanabe
Eiju
E
Ozawa
Keiya
K
Nakano
Imaharu
I
D000368:Aged; D001142:Aromatic-L-Amino-Acid Decarboxylases / Q000235:genetics / Q000378:metabolism*; D005260:Female; D015316:Genetic Therapy / Q000379:methods*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000235:genetics / Q000378:metabolism* / Q000628:therapy*; D049268:Positron-Emission Tomography; D016896:Treatment Outcome
D001142:Aromatic-L-Amino-Acid Decarboxylases