Emerging therapies for Parkinson's disease

Purpose of review The experimental therapeutics of Parkinson's disease are reviewed, highlighting the current pipeline of emerging therapeutic approaches. Recent findings This review includes novel approaches to dopaminergic drug delivery such as intraintestinal infusions or new extended-release formulations of levodopa and also intrapulmonary delivery of apomorphine as well as novel dopaminergic agents like the monoamine oxidase-B inhibitor safinamide or novel catechol-O-methyl transferase inhibitors. An even greater number of ongoing clinical trials assess the efficacy and safety of nondopaminergic approaches to enhance motor control or reduce motor complications like fluctuations and dyskinesias. These include adenosine A(2A) antagonists, alpha-adrenergic and serotonergic agonists as well as drugs acting on the glutamatergic system. Gene-based or cell-based intrastriatal delivery of therapeutic principles that enhance striatal dopaminergic transmission directly or via the stimulation of trophic activity has also reached phase II clinical development with encouraging results in some studies. Finally, a wide spectrum of agents with a potential for slowing disease progression is currently tested. Summary A variety of medical and nonmedical interventions in different phases of clinical development provide an interesting and promising portfolio of emerging therapies for Parkinson's disease.