Merck (MRK) Thursday announced the discontinuation of the extension phases of its studies on investigational adenosine A2A receptor antagonist for the treatment of Parkinson's disease, as initial review of data from three Phase III trials did not provide evidence of efficacy for preladenant compared with placebo.
Issuing an update on the clinical program for preladenant, Merck said it no longer plans to pursue regulatory filings for preladenant. The decision to discontinue is not based on any safety finding.
The results of these studies will be presented at an upcoming scientific meeting and will be submitted for publication in a peer-reviewed journal.
The Phase III clinical program for preladenant included three randomized, controlled clinical trials to evaluate safety and efficacy. Two of these studies assessed preladenant when added to levodopa therapy in patients with moderate-to-severe PD. The remaining one assessed preladenant as monotherapy in early PD.
David Michelson, vice president, clinical research, Neuroscience and Ophthalmology at Merck Research Laboratories, said, ''While these results are disappointing, this program is an important example of Merck's continued commitment to pursue promising science with the goal of bringing forward medicines that address important unmet medical needs."
MRK closed up 1.3 percent at $47.33 on Thursday.
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