Several small-cap names posted sharp gains in Thursday's after-hours session, driven by fresh corporate updates, clinical developments, and strategic pivots. Below are five stocks that stood out for their notable post-close moves and underlying catalysts.Shares of MEDIROM Healthcare Technologies Inc. (MRM) surged dramatically in after-hours trading on Thursday, climbing 282.8% to $5.55 as of 11:41 PM EDT. The sharp spike followed news that the company will double the installation of its biometric authentic ...