Advances in Therapeutics for Hyperkinetic Movement Disorders

Hyperkinetic movement disorders include a diverse group of conditions such as myoclonus, tremor, dystonia and chorea. In the last two decades, major advances have been made in the understanding of the major hyperkinetic disorders, and these advances are influencing the treatment of patients with these conditions. For example, our current understanding of the genetics of disorders such as Huntington’s disease has opened new approaches for gene therapy which can potentially transform a disorder from untreatable to treatable. Nevertheless, neurodegenerative disorders are complex as they are not comprised of only motor aspects, but also neuropsychiatric and cognitive features. Further insights into the pathophysiology of movement disorders have shed light on new potential therapies. For example, recent work on neuronal brain iron accumulation disorders, particularly pantothenate kinase-associated neurodegeneration, has offered new therapeutic targets. Finally, even well-established therapies such as deep brain stimulation have been expanding.

In this Research Topic, internationally known investigators will review clinical features including phenomenology, diagnostic approach, as well as clinically available and developing treatments of hyperkinetic movement disorders. We aim to expand our understanding of hyperkinetic movement disorders, with a focus on the novel therapeutic interventions that are currently being developed. The genetic and pathophysiological bases of these hyperkinetic movement disorders will be introduced in order to demonstrate their implications regarding genetically- and pathophysiology-oriented therapeutic approaches. We hope that this Research Topic will illustrate the challenges and opportunities for discovery in the coming years.

Therefore, for this Research Topic we welcome manuscript submissions on the following topics:

• An overview of the major hyperkinetic movement disorders, how they are defined clinically, and how they are managed in tertiary care centers throughout the world;
• How novel gene therapy approaches (e.g. siRNA, gene delivery) will change our treatment of “untreatable” neurodegenerative hyperkinetic movement disorders (e.g. Huntington’s disease, chorea acanthocytosis, spinocerebellar ataxias);
• How our improved understanding of the biologic pathways underlying rare hyperkinetic disorders will change treatment paradigms (e.g. NBIA disorders such as PANK2, PLA2G6; Friedreich’s ataxia; Ataxia Telangiectasia);
• How the application of current and future deep brain stimulation paradigms will change the management of hyperkinetic movement disorders (e.g. genetic dystonias, myoclonus-dystonia, progressive myoclonic epilepsies.)

We would like to acknowledge that Dr. Pichet Termsarasab, Mahidol University, has acted as a coordinator and has contributed to the preparation of the proposal for this Research Topic.

_{Topic Editor TK has received grants, personal fees and other support from companies involved in NBIA studies (ApoPharma Inc, Retrophin Pharmaceuticals, Comet Therapeutics, CoA Therapeutics) . ER has served on scientific advisory boards for Orkyn, Aguettant, Merz-Pharma and has received funding from Merz-Pharma, Orkyn, Aguettant, Elivie, Ipsen, Everpharma, Fondation Desmarest, AMADYS, Fonds de Dotation Brou de Laurière, Agence Nationale de la Recherche. All other Topic Editors declare no competing interests with regards to the Research Topic subject.}