MannKind Corp. Chief Executive Hakan Edstrom announced his resignation from the Valencia biopharmaceutical company Friday.

The board of directors elected Alfred Mann, the billionaire founder of the company, as interim chief executive. In addition, a committee of the board will begin looking for a new chief executive immediately.

MannKind has experienced some setbacks lately. Sales of Afrezza, the company’s fast-acting inhalable insulin and its only commercial product, have also been disappointing. Originally, Wall Street analysts estimated the drug could reach $2 billion in sales but it has produced less than $6 million.

The company just recently listed its stock on the Tel Aviv Stock Exchange, hoping to fund the company into 2017. It anticipated raising approximately $120 million in cash but has generated $36 million.

MannKind shares closed up 6 cents or 2.5 percent to $2.47 on the Nasdaq.