Mirum Pharmaceuticals, Inc.

During our last fiscal quarter, our directors and officers (as defined in Rule 16a-1(f) under the Exchange Act)adopted orterminated the contracts, instructions or written plans for the purchase or sale of our securities set forth in the table below.

(a) This number includes shares of our common stock issuable pursuant to awards of unvested restricted stock units (“RSUs”) and unvested performance stock units (“PSUs”). The PSUs are subject to the achievement of certain performance conditions as set forth in the applicable PSU agreement. The actual number of PSUs that vest following the end of an applicable performance period, if any, varies and therefore the resulting shares of our common stock available for sale under the plan will depend on the attainment of the performance metrics. The maximum number of shares to be sold will be reduced by net shares withheld to satisfy tax withholding obligations that arise in connection with the vesting and settlement. For purposes of this disclosure, we have reported the maximum aggregate number of shares to be sold without subtracting any shares to be withheld upon future vesting events and assumed the maximum payout of the PSUs.