New therapies for the treatment of Parkinson's disease: adenosine A2A receptor antagonists

The development of non-dopaminergic therapies for the treatment of Parkinson's disease (PD) has attracted much interest in recent years. Among new different classes of drugs, adenosine A(2A) receptor antagonists have emerged as best candidates. The present review will provide an updated summary of the results reported in literature concerning the effects of adenosine A(2A) antagonists in rodent and primate models of PD. These results show that A(2A) receptor antagonists improve motor deficits without inducing dyskinesia and counteract parkinsonian tremor. In progress clinical trials have shown that a low dose of L-DOPA plus KW-6002 produced symptomatic relief no different from that produced by an optimal dose of L-DOPA alone, whereas dyskinesias were reduced rendering this class of compounds particularly attractive. (c) 2005 Elsevier Inc. All rights reserved.