Swiss pharmaceutical company Novartis on Monday announced that Chief Executive Joseph Jimenez will retire in 2018. The pharmaceutical major said chief drug developer Vasant Narasimhan will take over from Jiminez on February 1, Reuters reported.

“I have been CEO for eight years and I have been pretty public about the fact that I did not think a CEO should stay much longer than that,” Jimenez said to Bloomberg. “You come in, you see what you want to change, you change it, and then it is time to pass it on to a successor.”

Jimenez, who joined Novartis in 2007 and became the CEO in 2010, will step down after having successfully secured the approval of the United States for a new gene therapy for leukemia last week. Narasimhan, who is of Indian origin, said, “I feel honoured and humbled to be asked to lead Novartis. We will continue our legacy of bringing leading innovation to patients around the world.”

Jimenez had in July expressed confidence that the pharmaceutical major would return to sales growth. Shares of Novartis fell on the Zurich stock exchange after the company’s announcement on Monday.