UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549


SCHEDULE 13G

Under the Securities Exchange Act of 1934


Amendment No.: 0*


Name of Issuer: Mirum Pharmaceuticals, Inc.


Title of Class of Securities: Common Stock


CUSIP Number: 604749101


Date of Event Which Requires Filing of this Statement: 6/28/2024


Check the appropriate box to designate the rule pursuant to which this
Schedule is filed.

[X] Rule 13d-1(b)
[ ] Rule 13d-1(c)
[ ] Rule 13d-1(d)

* The remainder of this cover page shall be filled out for a reporting
person's initial filing on this form with respect to the subject class
of securities, and for any subsequent amendment containing information
which would alter the disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not
be deemed to be "filed" for the purpose of Section 18 of the Securities
Exchange Act of 1934 ("Act") or otherwise subject to the liabilities of
that section of the Act but shall be subject to all other provisions of
the Act (however, see the Notes).


CUSIP No.: 604749101

1.  NAME OF REPORTING PERSON
    S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
    Janus Henderson Group plc
    EIN #00-0000000

2.  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
    a.   ___
    b.   ___

3.  SEC USE ONLY

4.  CITIZENSHIP OR PLACE OF ORGANIZATION
         Jersey, Channel Islands

NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:

5.   SOLE VOTING POWER
     0**

6.   SHARED VOTING POWER
     4,988,747**

7.   SOLE DISPOSITIVE POWER
     0**

8.   SHARED DISPOSITIVE POWER
     4,988,747**

9.   AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
     4,988,747**

10.  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN
SHARES
     Not applicable

11.  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
     10.6%**

12.  TYPE OF REPORTING PERSON
     IA, HC

** See Item 4 of this filing

Item 1.
    (a). Name of Issuer: Mirum Pharmaceuticals, Inc. ("Mirum")

    (b). Address of Issuer's Principal Executive Offices:

         989 East Hillsdale Boulevard, Suite 300
         Foster City, CA 94404

Item 2.
    (a).-(c). Name, Principal Business Address, and Citizenship of
  Persons Filing:

         (1)  Janus Henderson Group plc
              201 Bishopsgate
              EC2M 3AE, United Kingdom
        Citizenship: Jersey, Channel Islands

    (d). Title of Class of Securities:  Common Stock

    (e). CUSIP Number:  604749101

Item 3.

This statement is filed pursuant to Rule 13d-1(b) or 13d-2(b) and the
person filing, Janus Henderson Group plc ("Janus Henderson") is a
parent holding company/control person in accordance with Section
240.13d-1(b)(ii)(G). See Item 4 for additional information.

Item 4.  Ownership

The information in items 1 and 5 through 11 on the cover page(s) on
Schedule 13G is hereby incorporated by reference.

Janus Henderson has a 100% ownership stake in Janus Henderson Investors
U.S. LLC ("JHIUS"), Janus Henderson Investors UK Limited ("JHIUKL") and
Janus Henderson Investors Australia Institutional Funds Management
Limited ("JHIAIFML"), (each an "Asset Manager" and collectively as the
"Asset Managers"). Due to the above ownership structure, holdings for
the Asset Managers are aggregated for purposes of this filing. Each
Asset Manager is an investment adviser registered or authorized in its
relevant jurisdiction and each furnishing investment advice to various
fund, individual and/or institutional clients (collectively referred to
herein as "Managed Portfolios").

As a result of its role as investment adviser or sub-adviser to the
Managed Portfolios, JHIUS may be deemed to be the beneficial owner of
4,966,689 shares or 10.5% of the shares outstanding of Mirum Common
Stock held by such Managed Portfolios. However, JHIUS does not have the
right to receive any dividends from, or the proceeds from the sale of,
the securities held in the Managed Portfolios and disclaims any
ownership associated with such rights.

Item 5.  Ownership of Five Percent or Less of a Class

Not applicable.

Item 6.  Ownership of More than Five Percent on Behalf of Another Person

The Managed Portfolios, set forth in Item 4 above, have the right to
receive all dividends from, and the proceeds from the sale of, the
securities held in their respective accounts.

The interest of any one such Managed Portfolio does not exceed 5% of
the class of securities.

These shares were acquired in the ordinary course of business, and not
with the purpose of changing or influencing control of the Issuer.

Item 7.  Identification and Classification of the Subsidiary Which
Acquired the Security Being Reported on by the Parent Holding Company

JHIUS, JHIUKL and JHIAIFML are indirect subsidiaries of Janus Henderson
and are registered investment advisers furnishing investment advice to
Managed Portfolios.

Item 8.  Identification and Classification of Members of the Group

Not applicable.

Item 9.  Notice of Dissolution of Group

Not applicable.

Item 10. Certification

By signing below I certify that, to the best of my knowledge and
belief, the securities referred to above were acquired in the ordinary
course of business and were not acquired for the purpose of and do not
have the effect of changing or influencing the control of the issuer of
such securities and were not acquired in connection with or as a
participant in any transaction having such purposes or effect.


SIGNATURES

After reasonable inquiry and to the best of my knowledge and belief, I
certify that the information set forth in this statement is true,
complete and correct.

JANUS HENDERSON GROUP PLC

By  /s/  Kristin Mariani
Kristin Mariani, Head of North America Compliance, CCO
Date 7/10/2024

Name/Title Attorney-In-Fact

The original statement shall be signed by each person on whose behalf
the statement is filed or his or her authorized representative. If the
statement is signed on behalf of a person by his or her authorized
representative other than an executive officer or general partner of
the filing person, evidence of the representative's authority to sign
on behalf of such person shall be filed with the statement (see Exhibit
A), provided, however, that a power of attorney for this purpose which
is already on file with the Commission may be incorporated by
reference. The name and any title of each person who signs the
statement shall be typed or printed beneath his or her signature.


EXHIBIT A

POWER OF ATTORNEY

The undersigned, Janus Henderson Group plc ("the Company"), does hereby
make, constitute and appoint each of Kristin Mariani and Caroline
Barotti acting severally, as its true and lawful attorneys in-fact, for
the purpose of, from time to time, executing in its name and on its
behalf, whether the Company individually or as representative of
others, any and all documents, certificates, instruments, statements,
other filings and amendments to the foregoing (collectively,
"documents") determined by such person to be necessary or appropriate
to comply with ownership or control-person reporting requirements
imposed by any United States or non-United States governmental or
regulatory authority, including, without limitation, Forms 13D, 13F,
13G and 13H and any amendments to any of the foregoing as may be
required to be filed with the Securities and Exchange Commission, and
delivering, furnishing or filing any such documents with the
appropriate governmental, regulatory authority or other person, and
giving and granting to each such attorney-in-fact power and authority
to act in the premises as fully and to all intents and purposes as the
Company might or could do if personally present by one of its
authorized signatories, hereby ratifying and confirming all that said
attorney-in-fact shall lawfully do or cause to be done by virtue
hereof. Any such determination by an attorney-in-fact named herein
shall be conclusively evidenced by such person's execution, delivery,
furnishing or filing of the applicable document.

This power of attorney shall be valid from the date hereof and shall
remain in full force and effect until either revoked in writing by the
Company, or, in respect of any attorney-in-fact named herein, until
such person ceases to be an employee of the Company or one of its
affiliates.

IN WITNESS WHEREOF, the undersigned has caused this power of attorney
to be executed as of this 9th day of December, 2022.

Janus Henderson Group plc

By:  /s/ Michelle Rosenberg
Name: Michelle Rosenberg
Title: General Counsel and Company Secretary