 Stock and vaccine maker Moderna faded today following new data showing fading effectiveness of its RSV shot. Shares fell 11 percent after the CDC said Moderna's vaccine dropped from 55 percent efficacy over the first year to just 36 in the second. That compares to Pfizer's RSV shot, which has 74 percent efficacy in the second year and GlaxoSmithKline's 59 percent second year efficacy.