U.S. stocks reversed earlier gains to trade lower at session's half, as lingering optimism following Friday's friendly labor market data dissipated. Earlier, signs of limited wage inflation, watered-down trade tariffs and a warmer relationship between the U.S. and North Korea helped buoy stocks. Savara (SVRA) sank nearly 5% after the early-stage pharmaceuticals company Sunday said its Aironite drug candidate failed to meet its primary or secondary endpoints of symptom relief during phase II testing in patients with heart failure with preserved ejection fraction.