Moderna Inc’s COVID-19 vaccine appeared set for regulatory authorization this week after U.S. FDA staff endorsed it as safe and effective in documents released Tuesday. … the government is counting on the Moderna shot to help fulfill its promise to inoculate 20 million this month. An FDA decision on whether to issue a so-called emergency use authorization for the Moderna vaccine will be made after a panel of outside advisers meets Thursday. The FDA typically follows the advice of the panel, but is not required to do so.