Sen. Bernie Sanders (I-Vt.), chair of the Senate Committee on Health, Education, Labor and Pensions (HELP), along with Democrats on the committee, has launched an investigation into the high price of asthma inhalers in the U.S., targeting four makers of the devices — AstraZeneca, Boehringer Ingelheim, GlaxoSmithKline (GSK) and Teva Pharmaceuticals.