Mirum CEO exercises RSUs, sells shares for taxes

Mirum Pharmaceuticals CEO Christopher Peetz reported a mix of stock exercises and a tax-related sale.

Accepted by SEC EDGAR 03/17/2026 - 07:30 PM EDT Learn about SEC filing dates

Rhea-AI Filing Summary

Mirum Pharmaceuticals CEO Christopher Peetz reported a mix of stock exercises and a tax-related sale. On March 15, 2026, he exercised performance restricted stock units covering 75,000 shares of common stock at a conversion price of $0.00, increasing his direct holdings.

On March 16, 2026, Peetz executed an open-market sale of 40,985 shares of common stock at an average price of $91.9779 per share. A footnote states these shares were sold to cover tax withholding obligations tied to the vesting of the performance restricted stock units, indicating a mechanistic, tax-driven transaction rather than a discretionary sale. After these transactions, he directly held 194,309 shares, with an additional 187,500 shares held indirectly by The Peetz Family Trust.

Insider Trade Summary

Exercise and sale activity reported; no spread calculated

Exercise and Sale 5 txns

Insider Peetz Christopher

Role CHIEF EXECUTIVE OFFICER

Sold 40,985 shs ($3.77M)

Approx. gross sale proceeds $3.77M

Approx. exercise cost $0.00

Type	Security	Shares	Price	Value
Sale	Common Stock	40,985	$91.9779	$3.77M
Exercise	Performance Restricted Stock Units	25,000	$0.00	$0.00
Exercise	Performance Restricted Stock Units	50,000	$0.00	$0.00
Exercise	Common Stock	25,000	$0.00	$0.00
Exercise	Common Stock	50,000	$0.00	$0.00
Holding	Common Stock	--	--	--

Holdings After Transaction: Performance Restricted Stock Units — 25,000 contracts (Direct); Common Stock — 194,309 shares (Direct); Common Stock — 187,500 shares (Indirect, By The Peetz Family Trust)

Footnotes (4)

1. F1. Each performance restricted stock unit represents a contingent right to receive one share of the Issuer's common stock.
2. F2. Shares sold to cover tax withholding obligations associated with the vesting of the performance restricted stock units.
3. F3. The shares vest as follows: 2/3 of the shares vest on March 15, 2025 and 1/3 of the shares vest on March 15, 2026.
4. F4. The shares vest as follows: 2/3 of the shares vest on March 15, 2026 and 1/3 of the shares vest on March 15, 2027.

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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).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Peetz Christopher

(Last) (First) (Middle)

C/O MIRUM PHARMACEUTICALS, INC.

989 E HILLSDALE BLVD., SUITE 300

(Street)

FOSTER CITY CA 94404

(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)

X	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	CHIEF EXECUTIVE OFFICER

3. Date of Earliest Transaction (Month/Day/Year)
03/15/2026

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	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	03/15/2026		M		25,000	A	(1)	185,294	D
Common Stock	03/15/2026		M		50,000	A	(1)	235,294	D
Common Stock	03/16/2026		S(2)		40,985	D	$91.9779	194,309	D
Common Stock								187,500	I	By The Peetz Family Trust

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
Performance Restricted Stock Units	(1)	03/15/2026		M			25,000	(3)	(3)	Common Stock	25,000	$0	0	D
Performance Restricted Stock Units	(1)	03/15/2026		M			50,000	(4)	(4)	Common Stock	50,000	$0	25,000	D

Explanation of Responses:

1. Each performance restricted stock unit represents a contingent right to receive one share of the Issuer's common stock.

2. Shares sold to cover tax withholding obligations associated with the vesting of the performance restricted stock units.

3. The shares vest as follows: 2/3 of the shares vest on March 15, 2025 and 1/3 of the shares vest on March 15, 2026.

4. The shares vest as follows: 2/3 of the shares vest on March 15, 2026 and 1/3 of the shares vest on March 15, 2027.

	/s/ Judit Ryvkin, Attorney-in-Fact	03/17/2026
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
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