After less than one year on the job, Melinta Therapeutics (NASDAQ: MLNT) CEO John Johnson has resigned “due to changes in the company’s circumstances and in order to pursue other opportunities,” the antibiotics developer announced Friday. He also stepped down from the Morristown, NJ-based company’s board of directors. Melinta said Johnson will serve as acting CEO for at least 30 days to help with the transition of his duties and the search for his successor. The board has asked Johnson to advise the company for the next six months. Johnson was appointed interim CEO of Melinta in October. In February, he was named the permanent CEO.