MIRM · Mirum Pharmaceuticals, Inc. · Insider Trading

1/4th of the shares vest one year after September 21, 2026 (the "Vesting Commencement Date") and the balance of the shares vest in a series of 36 successive equal monthly installments measured from the first anniversary of the Vesting Commencement Date.

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

1/3rd of the shares subject to the restricted stock units shall vest on each anniversary of September 21, 2026 (the "Vesting Commencement Date"), such that the entire award will be vested on the three-year anniversary of the Vesting Commencement Date.

The stock option is fully vested.

The stock option is fully vested.

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

Each restricted stock unit represents a contingent right to receive one share of common stock (or its cash equivalent, at the discretion of the Issuer).

Each restricted stock unit represents a contingent right to receive one share of common stock (or its cash equivalent, at the discretion of the Issuer).

The restricted stock units vest in a series of three successive equal annual installments beginning on the one-year anniversary of September 11, 2023.

Reported transaction occurred pursuant to a Rule 10b5-1 Plan adopted by the reporting person on March 18, 2026.

The stock option is fully vested.

Includes 131 shares of Common Stock that were acquired by the Reporting Person on May 10, 2026, pursuant to the Issuer's Employee Stock Purchase Plan.

Reported transaction occurred pursuant to a Rule 10b5-1 Plan adopted by the reporting person on March 2, 2026.

The weighted average sale price for the transaction reported was $98.08, and the range of prices were between $97.47 and $98.42. Upon request by the SEC staff, the Issuer, or any security holder of the Issuer, full information regarding the number of shares sold at each separate price will be provided.

Reported transaction occurred pursuant to a Rule 10b5-1 Plan adopted by the reporting person on March 2, 2026.

The weighted average sale price for the transaction reported was $98.91, and the range of prices were between $98.49 and $99.38. Upon request by the SEC staff, the Issuer, or any security holder of the Issuer, full information regarding the number of shares sold at each separate price will be provided.

The stock option is fully vested.

Reported transaction occurred pursuant to a Rule 10b5-1 Plan adopted by the reporting person on March 9, 2026.

. The weighted average sale price for the transaction reported was $99.901633, and the range of prices were between $99.90 and $99.93. Upon request by the SEC staff, the Issuer, or any security holder of the Issuer, full information regarding the number of shares sold at each separate price will be provided.

Includes 175 shares of common stock that were acquired by the Reporting Person on May 10, 2026, pursuant to the Issuer's Employee Stock Purchase Plan.

The stock option is fully vested.

Reported transaction occurred pursuant to a Rule 10b5-1 Plan adopted by the reporting person on March 2, 2026.

The weighted average sale price for the transaction reported was $100.14, and the range of prices were between $99.995 and $100.2425. Upon request by the SEC staff, the Issuer, or any security holder of the Issuer, full information regarding the number of shares sold at each separate price will be provided.

Reported transaction occurred pursuant to a Rule 10b5-1 Plan adopted by the reporting person on March 2, 2026.

The weighted average sale price for the transaction reported was $98.51, and the range of prices were between $97.93 and $98.92. Upon request by the SEC staff, the Issuer, or any security holder of the Issuer, full information regarding the number of shares sold at each separate price will be provided.

Reported transaction occurred pursuant to a Rule 10b5-1 Plan adopted by the reporting person on March 2, 2026.

The weighted average sale price for the transaction reported was $99.25, and the range of prices were between $98.94 and $99.655. Upon request by the SEC staff, the Issuer, or any security holder of the Issuer, full information regarding the number of shares sold at each separate price will be provided.

Reported transaction occurred pursuant to a Rule 10b5-1 Plan adopted by the reporting person on March 18, 2026.

Reported transaction occurred pursuant to a Rule 10b5-1 Plan adopted by the reporting person on March 2, 2026.

The weighted average sale price for the transaction reported was $122.34, and the range of prices were between $122.13 and $123.1125. Upon request by the SEC staff, the Issuer, or any security holder of the Issuer, full information regarding the number of shares sold at each separate price will be provided.

Reported transaction occurred pursuant to a Rule 10b5-1 Plan adopted by the reporting person on March 9, 2026.

Reported transaction occurred pursuant to a Rule 10b5-1 Plan adopted by the reporting person on March 2, 2026.

The weighted average sale price for the transaction reported was $123.74, and the range of prices were between $123.24 and $124.10. Upon request by the SEC staff, the Issuer, or any security holder of the Issuer, full information regarding the number of shares sold at each separate price will be provided.

The stock option is fully vested.

Reported transaction occurred pursuant to a Rule 10b5-1 Plan adopted by the reporting person on March 2, 2026.

The weighted average sale price for the transaction reported was $121.65, and the range of prices were between $121.11 and $122.105. Upon request by the SEC staff, the Issuer, or any security holder of the Issuer, full information regarding the number of shares sold at each separate price will be provided.

Reported transaction occurred pursuant to a Rule 10b5-1 Plan adopted by the reporting person on March 9, 2026.

. The weighted average sale price for the transaction reported was $121.67, and the range of prices were between $121.13 and $122.13. Upon request by the SEC staff, the Issuer, or any security holder of the Issuer, full information regarding the number of shares sold at each separate price will be provided.

Reported transaction occurred pursuant to a Rule 10b5-1 Plan adopted by the reporting person on March 9, 2026.

. The weighted average sale price for the transaction reported was $123.84, and the range of prices were between $123.285 and $124.27. Upon request by the SEC staff, the Issuer, or any security holder of the Issuer, full information regarding the number of shares sold at each separate price will be provided.

Reported transaction occurred pursuant to a Rule 10b5-1 Plan adopted by the reporting person on March 2, 2026.

The weighted average sale price for the transaction reported was $124.79, and the range of prices were between $124.27 and $124.94. Upon request by the SEC staff, the Issuer, or any security holder of the Issuer, full information regarding the number of shares sold at each separate price will be provided.

Reported transaction occurred pursuant to a Rule 10b5-1 Plan adopted by the reporting person on March 9, 2026.

. The weighted average sale price for the transaction reported was $122.43, and the range of prices were between $122.235 and $123.10. Upon request by the SEC staff, the Issuer, or any security holder of the Issuer, full information regarding the number of shares sold at each separate price will be provided.

Reported transaction occurred pursuant to a Rule 10b5-1 Plan adopted by the reporting person on March 18, 2026.

Reported transaction occurred pursuant to a Rule 10b5-1 Plan adopted by the reporting person on March 18, 2026.

The shares vest on the first anniversary of the grant date, provided that the option will in any case be fully vested on the date of the Issuer's 2027 annual stockholder meeting.

The shares vest on the first anniversary of the grant date, provided that the option will in any case be fully vested on the date of the Issuer's 2027 annual stockholder meeting.

Each restricted stock unit represents a contingent right to receive one share of the Issuer's common stock and will vest on the first anniversary of the grant date, provided that it will in any case be fully vested on the date of the Issuer's 2027 annual stockholder meeting.

Each restricted stock unit represents a contingent right to receive one share of the Issuer's common stock and will vest on the first anniversary of the grant date, provided that it will in any case be fully vested on the date of the Issuer's 2027 annual stockholder meeting.

The shares vest on the first anniversary of the grant date, provided that the option will in any case be fully vested on the date of the Issuer's 2027 annual stockholder meeting.

Each restricted stock unit represents a contingent right to receive one share of the Issuer's common stock and will vest on the first anniversary of the grant date, provided that it will in any case be fully vested on the date of the Issuer's 2027 annual stockholder meeting.

The shares vest on the first anniversary of the grant date, provided that the option will in any case be fully vested on the date of the Issuer's 2027 annual stockholder meeting.

Each deferred stock unit represents a contingent right to receive one share of the Issuer's common stock and will vest on the first anniversary of the grant date, provided that it will in any case be fully vested on the date of the Issuer's 2027 annual stockholder meeting. Each vested deferred stock unit will be paid out in the Issuer's common stock upon the earliest to occur of (i) a change in control of the Issuer and (ii) within 60 days following separation from service with the Issuer.

The shares vest on the first anniversary of the grant date, provided that the option will in any case be fully vested on the date of the Issuer's 2027 annual stockholder meeting.

Each deferred stock unit represents a contingent right to receive one share of the Issuer's common stock and will vest on the first anniversary of the grant date, provided that it will in any case be fully vested on the date of the Issuer's 2027 annual stockholder meeting. Each vested deferred stock unit will be paid out in the Issuer's common stock upon the earliest to occur of (i) a change in control of the Issuer and (ii) within 60 days following separation from service with the Issuer.

The shares vest on the first anniversary of the grant date, provided that the option will in any case be fully vested on the date of the Issuer's 2027 annual stockholder meeting.

The shares vest on the first anniversary of the grant date, provided that the option will in any case be fully vested on the date of the Issuer's 2027 annual stockholder meeting.

Each deferred stock unit represents a contingent right to receive one share of the Issuer's common stock and will vest on the first anniversary of the grant date, provided that it will in any case be fully vested on the date of the Issuer's 2027 annual stockholder meeting. Each vested deferred stock unit will be paid out in the Issuer's common stock upon the earliest to occur of (i) a change in control of the Issuer and (ii) within 60 days following separation from service with the Issuer.

Each restricted stock unit represents a contingent right to receive one share of the Issuer's common stock and will vest on the first anniversary of the grant date, provided that it will in any case be fully vested on the date of the Issuer's 2027 annual stockholder meeting.