X0306 4 2019-07-22 0 0001759425 Mirum Pharmaceuticals, Inc. MIRM 0001694560 New Enterprise Associates 16, L.P. 1954 GREENSPRING DRIVE SUITE 600 TIMONIUM MD 21093 0 0 1 0 0001712881 NEA Partners 16, L.P. 1954 GREENSPRING DRIVE SUITE 600 TIMONIUM MD 21093 0 0 1 0 0001712882 NEA 16 GP, LLC 1954 GREENSPRING DRIVE SUITE 600 TIMONIUM MD 21093 0 0 1 0 Common Stock 2019-07-22 4 C 0 3736243 A 3736243 D Common Stock 2019-07-22 4 P 0 450000 15.00 A 4186243 D Series A Preferred Stock 2019-07-22 4 C 0 29889945 0.00 D Common Stock 3736243 0 D Automatic conversion, in connection with the Issuer's initial public offering, of each share of the Issuer's Series A preferred stock into 0.125 shares of the Issuer's common stock. The shares have no expiration date. The shares are directly held by New Enterprise Associates 16, L.P. ("NEA 16"), and indirectly held by NEA Partners 16, L.P. ("NEA Partners"), the sole general partner of NEA 16, NEA 16 GP, LLC ("NEA 16 GP"), the sole general partner of NEA Partners 16, and the individual managers of NEA 16 GP (NEA Partners 16, NEA 16 GP and the individual managers of NEA 16 GP, together, the "Indirect Reporting Persons").The individual managers of NEA 16 GP are Peter J. Barris, Forest Baskett, Ali Behbahani, Carmen Chang, Anthony A. Florence, Jr., Mohamad Makhzoumi, Josh Makower, David M. Mott, Scott D. Sandell, Peter W. Sonsini and Paul Walker. The Indirect Reporting Persons disclaim beneficial ownership within the meaning of Section 16 of the Securities Exchange Act of 1934, as amended, or otherwise of such portion of the shares of the Issuer held by NEA 16 in which the Indirect Reporting Persons have no pecuniary interest. The shares were purchased in the Issuer's initial public offering. /s/ Sasha Keough, attorney-in-fact 2019-07-24