Biotie Therapies Corp has announced that enrolment is complete in its Phase IIb trial evaluating tozadenant, which is licensed to UCB, in Parkinson's disease.

The 12-week study, which has enrolled earlier than expected, will involve 420 patients who are experiencing levodopa-related end of dose wearing off. The primary goal is to determine the efficacy of tozadenant in reducing the mean number of hours per day spent in the 'off' state. Top-line data is expected at the end of 2012.

If all goes well, UCB will be responsible for conducting the Phase III programme and commercialising tozadenant, an oral selective adenosine A2a receptor antagonist. Biotie obtained rights to the drug from Roche in 2007 for selected diseases of the central nervous system.

Biotie and UCB will be hoping tozadenant proves to be more successful than a previous PD drug they were working on. Last November, the latter decided not to exercise its option to license the Finnish drugmaker's nitisinone, after data from a Phase IIa study showed that the hydroxyphenylpyruvate dioxygenase inhibitor did not show a significant improvement in measures of Parkinson's motor function when compared to placebo.

Looking to partner Roche-returned drug

At the end of last month, Biotie got the rights back from Roche to SYN120, a novel selective 5-HT6 receptor antagonist, after the Swiss major backed out of developing the cognitive disorder compound for "strategic portfolio reasons".

Biotie chief executive Timo Veromaa noted that SYN120 "represents a truly exciting and differentiated product for the treatment of Alzheimer's disease, schizophrenia and other conditions". He added that "a number of reputable companies have already expressed an interest in the compound (which is ready to enter Phase II) and we are confident that we will find a high-quality partner".