Merck rose after Atea Pharmaceuticals Inc AVIR.O said its antiviral pill, being developed with Roche ROG.S, failed to help patients with mild and moderate COVID-19. By Shreyashi Sanyal and Sinéad Carew Oct 19 (Reuters) - U.S. stock indexes closed higher on Tuesday with the biggest boosts from the technology and healthcare sectors as investors appeared to bet on solid quarterly reports even as some worried that it was too early to celebrate. "Investors will be paying very close attention to pricing power, how companies are dealing with labor shortages and inflationary cost pressures within their business."