After postponing its IPO in May due to market conditions, Rib-X Pharmaceuticals Inc. turned back to the private markets. The company's new cash infusion should get it to a Phase III data event for its lead antibiotic, delafloxacin

Last week, the company raised $18.7 million in the first tranche of a $67.5 million series 2 preferred round comprising equity and an undisclosed amount of convertible debt. President and CEO Mark Leuchtenberger said Rib-X plans