SEC Form 4

FORM 4		UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940	OMB APPROVAL OMB Number: 3235-0287 Estimated average burden hours per response: 0.5
	Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person* Frazier Life Sciences IX, L.P. (Last) (First) (Middle) 70 WILLOW ROAD, STE. 200 (Street) MENLO PARK CA 94025 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol Mirum Pharmaceuticals, Inc. [ MIRM ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director X 10% Owner Officer (give title below) Other (specify below)
	3. Date of Earliest Transaction (Month/Day/Year) 07/22/2019
	4. If Amendment, Date of Original Filed (Month/Day/Year)	6. Individual or Joint/Group Filing (Check Applicable Line) Form filed by One Reporting Person X Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	07/22/2019		C		3,116,912(1)	A	(1)	3,116,912	D(2)
Common Stock	07/22/2019		P(3)		450,000	A	$15	3,566,912	D(2)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Series A Preferred Stock	(1)	07/22/2019		C			24,935,300	(1)	(1)	Common Stock	3,116,912(1)	$0.00	0	D(2)

1. Name and Address of Reporting Person* Frazier Life Sciences IX, L.P. (Last) (First) (Middle) 70 WILLOW ROAD, STE. 200 (Street) MENLO PARK CA 94025 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* FHMLS IX, L.P. (Last) (First) (Middle) 70 WILLOW ROAD, STE. 200 (Street) MENLO PARK CA 94025 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* FHMLS IX, L.L.C. (Last) (First) (Middle) 70 WILLOW ROAD, STE. 200 (Street) MENLO PARK CA 94025 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* Topper James N (Last) (First) (Middle) 70 WILLOW ROAD, STE. 200 (Street) MENLO PARK CA 94025 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

Explanation of Responses:

1. In connection with the Issuer's initial public offering, each share of the Issuer's Series A Preferred Stock automatically converted into 0.125 shares of the Issuer's Common Stock. The shares have no expiration date.

2. The shares are held directly by Frazier Life Sciences IX, L.P. FHMLS IX, L.P. is the general partner of Frazier Life Sciences IX, L.P. FHMLS IX, L.L.C. is the general partner of FHMLS IX, L.P. James N. Topper and Patrick Heron are the managing members of FHMLS IX, L.L.C. and share voting and dispositive power over the shares held by Frazier Life Sciences IX, L.P. Mr. Topper, FHMLS IX, L.P. and FHMLS IX, L.L.C. disclaim beneficial ownership of the shares held by Frazier Life Sciences IX, L.P., except to the extent of his or its pecuniary interest therein, if any.

3. The shares were purchased in the Issuer's initial public offering.

Remarks:

	Frazier Life Sciences IX, L.P. By: FHMLS IX, L.P., its general partner, By: FHMLS IX, L.L.C., its general partner, By: /s/ Steve Bailey, Chief Financial Officer	07/24/2019
	FHMLS IX, L.P. By: FHMLS IX, L.L.C., its general partner, By: /s/ Steve Bailey, Chief Financial Officer	07/24/2019
	FHMLS IX, L.L.C. By: /s/ Steve Bailey, Chief Financial Officer	07/24/2019
	/s/ Steve Bailey, Attorney-in-Fact for James N. Topper	07/24/2019
	** Signature of Reporting Person	Date
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