Conejo Valley biotech veteran Keith Leonard has been named chief executive of San Francisco-based Unity Biotechnology Inc. after the company received $116 million in funding.

Leonard was the former chief executive of Westlake Village-based Kythera Biopharmaceuticals Inc. prior to its $2.1 billion acquisition by drug giant Allergan Inc.

In his new job, he will replace his Kythera co-founder Nathaniel David, who will become Unity’s president.

Currently, Leonard also serves as executive chairman at Sienna Biopharmaceuticals Inc. in Westlake Village, which is developing laser treatments for acne and hair removal. Previously, Leonard worked at Thousand Oaks biotech Amgen Inc. for 13 years.

His newest endeavor, Unity, is focused on anti-aging drugs and just completed its $116 million Series B finance round. Funders included Amazon.com Inc. Chief Executive Jeff Bezos, Arch Venture Partners and Mayo Clinic Ventures.