X0306 4 2019-01-24 0 0001571498 Epizyme, Inc. EPZM 0001620152 Bazemore Robert B C/O EPIZYME, INC. 400 TECHNOLOGY SQUARE CAMBRIDGE MA 02139 1 1 0 0 President & CEO Common Stock 2019-01-24 4 A 0 75383 0.00 A 80068 D Stock Option (Right to Buy) 9.12 2019-01-24 4 A 0 347464 0.00 A 2029-01-23 Common Stock 347464 347464 D Consists of shares of Common Stock issuable under 75,383 restricted stock units ("RSUs") granted pursuant to the Company's 2013 Stock Incentive Plan. Each RSU represents the right to receive one share of Common Stock upon vesting. These RSUs are scheduled to vest in four equal annual installments over four years from the grant date, with the first installment vesting on January 24, 2020. This option was granted on January 24, 2019 pursuant to the Company's 2013 Stock Incentive Plan with respect to 347,464 shares of Common Stock, with 25% vesting on January 24, 2020 and the remaining 75% vesting in 36 substantially equal monthly installments thereafter. Exhibit Index: 24 Power of Attorney /s/ John Weidenbruch, attorney-in-fact 2019-01-28