POWER OF ATTORNEY

      Know  all  by  these  presents that the undersigned hereby constitutes and
appoints  each  of  Dayton  Misfeldt,  William  P.  Quinn, Tina Gulotta and John
McKenna  signing  individually,  the undersigned's true and lawful attorneys-in-
fact and agents to:

      (1)  execute  for and on behalf of the undersigned, an officer director or
holder  of  10%  or  more,  of  a  registered  class  of  securities  of Sunesis
Pharmaceuticals,  Inc.  (the  "COMPANY"),  Forms  3,  4 and 5 in accordance with
Section  16(a)of  the Securities Exchange Act of 1934, as amended (the "EXCHANGE
ACT") and the rules thereunder;

    (2) do  and  perform  any and all acts for and on behalf of the undersigned
that  may be necessary or desirable to complete and execute such Form 3, 4 or 5,
or  other  form  or  report,  complete  and  execute any amendment or amendments
thereto,  and  timely  file  such  forms  or  amendments  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 shall no longer be
employed by the Company or Cooley LLP, as the case may be.

    IN  WITNESS WHEREOF, the undersigned has caused this Power of Attorney to be
executed as of this 23rd day of September, 2019.

                                                     /s/ Nicole Onetto
                                                     ---------------------------
                                                     Nicole Onetto