Ken Hanover, who as president of Northeast Health System helped oversee the company’s merger with Lahey Clinic last spring, will resign from his post next week and leave the organization at the end of the year.

Hanover joined Northeast three years ago. Denis Conroy, who serves as chief integration officer of Lahey Health System — which was created in the spring after the merger — will become interim president on Nov. 15. Hanover will serve as executive vice president and chief strategy officer for Lahey Health System until Dec. 31.