X0306 4 2016-04-01 0 0001374690 ZAFGEN, INC. ZFGN 0001579130 McDonough Cameron Geoffrey C/O ZAFGEN, INC., 175 PORTLAND STREET BOSTON MA 02114 1 0 0 0 Common Stock 2016-04-01 4 D 0 4424 7.91 D 0 D Stock Option (Right to Buy) 7.91 2016-04-01 4 A 0 6100 A 2026-04-01 Common Stock 6100 6100 D In a Form 4 filed on January 27, 2016, a grant of 4,424 shares of common stock on January 25, 2016 (the "Original Grant") was reported on behalf of the Reporting Person in lieu of cash fees under the Non-Employee Director Compensation Policy (the "Policy") pursuant to a Restricted Stock Agreement at a price equal to $7.91 per share, the market price of the stock on the grant date (the "Original Price"), subject to vest over a period of one year starting January 1, 2016 on a quarterly basis in arrears. It was recently determined that the Original Grant was made owing to an administrative error, since the Reporting Person requested a stock option in lieu of cash fees under the Policy. (Continued from Footnote 1) To correct the error, the Company canceled the Original Grant on April 1, 2016 and granted a stock option (the "Replacement Option") to the Reporting Person in lieu of cash fees under the Policy pursuant to a Non-Qualified Stock Option Agreement at an exercise price equal to the Original Price, subject to vest over a period of one year starting January 1, 2016 on a quarterly basis in arrears. The correction is reported in this Form 4 as a cancellation of the Original Grant and the grant of the Replacement Option. /s/ Laurie Burlingame, Attorney-In-Fact 2016-04-04