POWER OF ATTORNEY

      The  undersigned  hereby  constitutes  and appoints Michael L. Lawhead and
Lisa  A. Latham, or any of them signing individually, the undersigned's true and
lawful attorney-in-fact (each, an "Attorney-in-Fact") to:

(1)   complete  and  execute,  for  and  on  behalf  of  the undersigned, in the
      undersigned's  capacity as an officer, director and/or beneficial owner of
      more  than  ten  percent  (10%)  of  any  equity  securities  of  Madrigal
      Pharmaceuticals,  Inc., a Delaware corporation (the "Company"), Forms 3, 4
      and  5,  and  Schedules  13D  and 13G, and such other forms and documents,
      including any amendments to any of the foregoing, as such Attorney-In-Fact
      shall  in  his  or  her  discretion  determine to be required or advisable
      pursuant to Section 16(a) and Section 13(d) of the Securities Exchange Act
      of  1934,  as  amended  (the "Exchange Act") and the rules and regulations
      promulgated  thereunder,  or  any  successor  laws  and  regulations, as a
      consequence of, or in respect of, the undersigned's ownership, acquisition
      or disposition of securities of the Company;

(2)   do and perform any and all acts for and on behalf of the undersigned which
      may  be  necessary or desirable to complete and execute any such forms and
      schedules,  including  any  amendments thereto, and timely file such forms
      and  schedules,  including  any amendments thereto, with the United States
      Securities  and  Exchange  Commission  (the  "SEC"),  and  any  securities
      exchange or similar authority; and

(3)   take  any  other  action  of  any  type  whatsoever in connection with the
      foregoing  which,  in  the  opinion  of  such  Attorney-in-Fact, may be of
      benefit  to,  in  the  best  interest  of,  or  legally  required  by, the
      undersigned,  it  being  understood  that  the  documents executed by such
      Attorney-in-Fact  on  behalf  of the undersigned pursuant to this Power of
      Attorney  shall be in such form and shall contain such information as such
      Attorney-in-Fact may approve in such Attorney-in-Fact's discretion.

      The undersigned hereby grants to each such Attorney-in-Fact full power and
authority  to  do and perform each and every act and thing whatsoever requisite,
necessary  or  proper to be done in the exercise of any of the rights and powers
herein granted, as fully to all intents and purposes as the undersigned might or
could  do if personally present, with full power of substitution and revocation,
hereby  ratifying  and  confirming  all that each such Attorney-in-Fact, or each
such Attorney-in-Fact's substitute or substitutes, shall lawfully do or cause to
be  done  by  virtue  of this power of attorney and the rights and powers herein
granted.   The   undersigned   acknowledges   that   each   of   the   foregoing
Attorneys-in-Fact,   in   serving  in  such  capacity  at  the  request  of  the
undersigned,  are  not  assuming,  nor  is  the  Company  assuming,  any  of the
undersigned's responsibilities to comply with Section 16(a) and Section 13(d) of
the Exchange Act.

      The  undersigned  agrees that each such Attorney-in-Fact may rely entirely
on  information  furnished  orally or in writing by the undersigned to each such
Attorney-in-Fact. The undersigned also agrees to indemnify and hold harmless the
Company  and  each  such Attorney-in-Fact against any losses, claims, damages or
liabilities (or actions in these respects) that arise out of or are based on any
untrue  statement  or omission of necessary facts in the information provided by
the   undersigned   to   such   Attorney-in-Fact   for  purposes  of  executing,
acknowledging,  delivering  and  filing  Forms 3, 4 and 5, and Schedules 13D and
13G,  including  any amendments thereto, and agrees to reimburse the Company and
each  such  Attorney-in-Fact for any legal or other expenses reasonably incurred
in  connection  with  investigating  or  defending against any such loss, claim,
damage, liability or action.

      This  Power  of  Attorney  shall remain in full force and effect until the
undersigned is no longer required to file Forms 3, 4 and 5, or Schedules 13D and
13G,  with  respect  to  the  undersigned's  holdings  of  and  transactions  in
securities issued by the Company, unless earlier revoked by the undersigned in a
signed writing delivered to the foregoing Attorneys-in-Fact.

      IN  WITNESS  WHEREOF, the undersigned has caused this Power of Attorney to
be executed as of this 21st day of July, 2016.

                                          /s/ Rebecca Taub
                                          -------------------------------
                                          Rebecca Taub, M.D.