http://www.reuters.com/article/rbssHealthcareNews/idUSBNG12626120080514
<p>May 14 (Reuters) – Geron Corp (GERN.O: Quote, Profile, Research) said U.S. health regulators placed a clinical hold on its investigational new drug submission for GRNOPC1, a cell therapy for spinal cord injury, sending its shares down 22 percent to their lowest in more than four years.</p> <p>"We have not yet received a letter from the FDA explaining the decision to place the submission on hold, so we are unable to comment specifically," Chief Executive Thomas Okarma said in…</p>