Disclosed is a method to provide a metal wire with a coating system comprising a primer and a topcoat, particularly a hydrophilic, lubricious topcoat. The method comprises applying directly onto the wire metal a primer coating composition, which is an aqueous coating composition comprising a multiphase vinyl polymer, the polymer comprising a first phase having a Tg in the range of from −20° C. to 40° C. and a hard phase having a Tg in the range of from 25° C. to 120° C. The primer has good adhesion to both the metal surface and the topcoat, and provides the eventual coating system with, inter alia, a good flexibility.