Newton-based HRPT Properties Trust has made changes to its senior management group.

The board of trustees of HRP elected John Mannix as president and chief investment officer, and David Lepore as senior vice president and chief operating officer. Mannix previously held the position of president and chief operating officer, and Lepore previously held the position of senior vice president.

The board also elected Jennifer Clark as secretary. She has resigned as a senior vice president of HRP. Clark remains executive vice president and general counsel of Reit Management & Research LLC, HRP’s manager, and will continue to supervise legal affairs affecting HRP and other companies managed by RMR, the company said.