GlycoMimetics, a clinical-stage biotech developing treatments for sickle cell episodes and AML, postponed its IPO on Friday. The Gaithersburg, MD-based company was founded in 2003 and booked $12 million in sales for the 12 months ended June 30, 2013. GlycoMimetics initially filed confidentially on August 21, 2013. Jefferies & Co. and Barclays were set to be the joint bookrunners on the deal.