X0306 4 2018-05-29 0 0001374690 ZAFGEN, INC. ZFGN 0001742110 McVeigh Brian C/O ZAFGEN, INC. 175 PORTLAND STREET, 4TH FLOOR BOSTON MA 02114 0 1 0 0 Chief Business Officer Stock Option (Right to Buy) 6.46 2018-05-29 4 A 0 225000 0.00 A 2028-05-29 Common Stock 225000 225000 D 25% of this option vests on May 29, 2019 and the remainder vests in equal monthly installments thereafter over a 3-year period. The option has been granted pursuant to an inducement award agreement outside of the company's 2014 Stock Option and Incentive Plan as a material inducement to the reporting person's acceptance of employment with the company in accordance with NASDAQ Listing Rule 5635(c)(4). The option is subject to acceleration upon a change in control pursuant to the terms of the reporting person's Severance and Change in Control Agreement dated as of May 29, 2018. /s/ Shoaib Ghias, Attorney-in-Fact 2018-05-30