COPENHAGEN, Oct 31 (Reuters) - Danish pharmaceutical group Lundbeck LUN.CO said on Thursday: * Japanese Otsuka 4768.T named as Lundbeck's partner in Japan on its nalmefene drug for the reduction of alcohol consumption. * The existing alliance between the two companies now also includes the development and commercialization of nalmefene in Japan. * Lundbeck receives an upfront payment of 50 million euros from Otsuka.Further company coverage: LUN.CO (Reporting by Teis Jensen) ((teis.jensen@thomsonreuters.com; +45 33969653; Reuters Messaging: teis.jensen.thomsonreuters.com@reuters.net)) Keywords: LUNDBECK OTSUKA/