Several biotech and healthcare stocks posted notable gains in after-hours trading, driven by clinical updates, strategic deals, and regulatory milestones. Below is a quick rundown of the top movers and the catalysts behind their price action.Genenta Science S.p.A. (GNTA) shares closed at $2.40, down 27.71$2.45, up 2.08%, in after-hours action. The volatility follows a pair of material announcements. On October 27, Genenta disclosed a $15 million registere ...