Melinta Therapeutics (NASDAQ: MLNT) CEO Dan Wechsler has stepped down from the company and its board of directors. In his place, the New Haven, CT, antibiotics company appointed board member John Johnson to serve as interim CEO. Wechsler joined Melinta last November. In a prepared statement, the company said he is leaving “to pursue other opportunities.” Melinta went public last year via a reverse merger with Cempra. The company’s portfolio also includes anti-bacterial drugs acquired from The Medicines Company (NASDAQ: MDCO).