Catalyst Pharma climbs on $4.1 billion buyout deal
** Shares of drugmaker Catalyst Pharmaceuticals CPRX.O rise 1.3% to $30.90 premarket ** Italy's Angelini Pharma says it will acquire Catalyst Pharmaceuticals in a $4.1 billion deal ** Angelini will pay $31.5 in cash for each Catalyst share, representing a 3% premium over the company's last closing price ** Catalyst specializes in the treatment of rare and difficult-to-treat conditions ** Up to last close, stock up 30.8% YTD (Reporting by Christy Santhosh) ((Christy.Santhosh@thomsonreuters.com))