CATALYST PHARMACEUTICALS, INC. has acquired an exclusive license to vamorolone, a potential treatment for Duchenne Muscular Dystrophy, for North America from Santhera Pharmaceuticals Holdings AG. With a $75 million all-cash purchase payment, the exclusive commercial rights extend to U.S., Canada, and Mexico. Catalyst Pharmaceuticals, INC. also has future rights for any approved indications of vamorolone and obtained a 11.26% stake in Santhera with a $15 million equity investment.