The first clinical trial of embryonic stem cells is on track to start early next year on patients with spinal cord injury. Geron, the California-based biotechnology company, will carry out the study on accident victims in six trauma centres across the US.

“The world’s spotlight will be on this trial,” Tom Okarma, Geron’s chief executive, told the Bio conference in Boston. To get it right, the company has carried out several years of preparatory work in collaboration with its academic partners at the University of California, Irvine.