By Raechel Thankam Job July 9 (Reuters) - AstraZeneca's nerve disease drug Wainua, made in partnership with Ionis, unexpectedly failed a pivotal heart-disease trial, hitting the firm's shares on Thursday and casting doubts over the UK-based drugmaker's trial design.

AstraZeneca and Ionis Pharmaceuticals shares are down roughly 8% and 20%, respectively, after the drugmakers said their heart therapy Wainua failed in a late-stage trial.