Michael Gilman keeps staring down retirement. The scientist and serial entrepreneur, late of Padlock Therapeutics Inc., which was sold last year to Bristol-Myers Squibb Co. for $600 million, has been splitting his time between Arrakis Therapeutics Inc., where he serves as CEO, and an Atlas Venture company focused on gene and cell therapy that was under wraps until this week. (See BioWorld Today, March 24, 2016, and Feb. 28, 2017.)