UK biotechnology firm Vernalis plans to add to its portfolio of drug candidates in the central nervous system category via the purchase of Canada’s Cita NeuroPharmaceuticals for $64.5 million dollars.

The acquisition brings in two drug candidates in clinical trials - CNP1512 (levodopa methylester) for Parkinson’s disease and CNP3381 for neuropathic pain. Earlier this month Vernalis also North American rights to acquired Apokyn (apomorphine hydrochloride injection), another treatment for Parkinson’s disease, from Mylan Laboratories for $23 million.

Vernalis said it would pay an initial sum of $29.5 million to buy Cita, funded by issuing 26.9 million shares, and would also make a deferred payment of up to $35 million, depending on the progress of Cita's two main drug candidates.

CNP1512 has completed Phase III trials in Europe and is already approved for use in Italy. Two other Phase III trials - one in North America and the other in Europe - are required for worldwide approvals and are scheduled to begin in the first half of 2006. Meanwhile, CNP3381 has cleared Phase I and is due to start a Phase II programme next year.

The UK firm has said it raise £42.7 million in a placing and open offer to help fund the development of CNP1512 and CNP3381.

Analysts at Nomura were unimpressed with the deal, suggesting it would stretch Vernalis’ resources and does not bring in products with ‘massive commercial potential’.