A Senate investigation of drug-price spikes at four companies kicked off Wednesday with specialists from all corners of the health-care system testifying that they're powerless to manage the out-of-control prescription costs. The hearing launches the Special Committee on Aging's investigation into the soaring prices of old drugs, including the recent overnight price hike of Daraprim from $18 to $750. Doctors and policy experts offered a slew of proposed policy solutions, such as expediting applications for generic drugs to increase competition and requiring companies to reveal how much drugs really cost.