The battle between business ­heavyweights over the future of ­QRxPharma has turned personal with the embattled drug developer refusing to send out a statement to shareholders from disgruntled billionaire investor Lang Walker it says is defamatory.

Mr Walker is attempting to spill two QRxPharma directors, founder Gary Pace and chairman Peter Farrell, and replace them with investment advisor Bruce Hancox and former Acrux CEO Richard Treagus. The Walker Group, which controls about 10 per cent of QRxPharma, has received details of the shareholder register and will distribute a member statement this week.