POWER OF ATTORNEY
       Know all by these present that the undersigned hereby constitutes
and appoints each of DINESH V. PATEL, PH.D., DONALD A. KALKOFEN and
MICHAEL TENTA, signing individually, the undersigned's true and lawful
attorneys-in-fact and agents to:
       (1) execute for and on behalf of the undersigned, in the
undersigned's capacity as an officer, director or beneficial owner of more
than 10% of a registered class of securities of Protagonist Therapeutics,
Inc. (the "Company"), (a) Forms 3, 4 and 5 (including any amendments
thereto) in accordance with Section 16(a) of the Securities Exchange Act
of 1934, as amended (the "Exchange Act") and the rules thereunder and a (b)
Form ID, Uniform Application for Access Codes to File on EDGAR, including
Update Passphrase Confirmation;
       (2) do and perform any and all acts for and on behalf of the
undersigned that may be necessary or desirable to execute such Forms 3, 4
or 5 or Form ID (including any amendments thereto) and timely file such
forms with the United States Securities and Exchange Commission and any
stock exchange or similar authority; and
       (3) take any other action of any nature whatsoever in connection
with the foregoing which, in the opinion of such attorney-in-fact, may be
of benefit, 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 terms and conditions
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 any 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 or revocation, hereby ratifying and confirming
all that such attorney-in-fact, or 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 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 of the Exchange Act.
       This Power of Attorney shall remain in full force and effect until
the earliest to occur of (a) the undersigned is no longer required to file
Forms 3, 4 and 5 with respect to the undersigned's holdings of and
transactions in securities issued by the Company, (b) revocation by the
undersigned in a signed writing delivered to the foregoing attorneys-in-
fact or (c) as to any attorney-in-fact individually, until such attorney-
in-fact is no longer employed by the Company or Cooley LLP.
       IN WITNESS WHEREOF, the undersigned has caused this Power of
Attorney to be executed as of August 13, 2020.
/s/ Sarah O'Dowd
Sarah O'Dowd