U.S. Food and Drug Administration Commissioner Dr. Scott Gottlieb said in a letter to staff Tuesday that he will be leaving the agency, effective in about a month.

The 46-year-old physician, former venture capitalist and drug consultant said he wishes to spend more time with his family.   “There’s perhaps nothing that could pull me away from this role other than the challenge of being apart from my family for these past two years and missing my wife and three young children,” Gottlieb said in the letter.

An administration official familiar with the situation said the move has been in the works for several months. Gottlieb has been commuting weekly to Washington from his home in Connecticut and is leaving to spend more time with his family, the official said.

Gottlieb tweeted that he is “grateful for the opportunity to help lead this wonderful agency.”