Canada-based Microbix has slapped Novartis ($NVS) with a lawsuit in Europe, where it says the Swiss pharma giant has infringed its patent on Virusmax--a technology used for increasing virus yields in egg-based vaccine manufacturing. The latest litigation is part of an ongoing legal tussle between the two companies: According to Microbix, Novartis has previously challenged its IP shield and is appealing a January decision from the European Patent Office that Virusmax is a novel, useful and nonobvious invention. A Novartis spokeswoman told FierceVaccines the Basel-based drugmaker could not comment. Release