February 11, 2026

Mark Litton
President and Chief Executive Officer
LeonaBio, Inc.
18706 North Creek Pkwy, Suite 104
Bothell, WA 98011

       Re: LeonaBio, Inc.
           Registration Statement on Form S-3
           Filed January 20, 2026
           File No. 333-292826
Dear Mark Litton:

       We have conducted a limited review of your registration statement and
have the
following comment.

       Please respond to this letter by amending your registration statement
and providing the
requested information. If you do not believe the comment applies to your facts
and
circumstances or do not believe an amendment is appropriate, please tell us why
in your
response.

       After reviewing any amendment to your registration statement and the
information you
provide in response to this letter, we may have additional comments.

Registration Statement on Form S-3
General

1.     We note from your Current Report on Form 8-K filed December 18, 2025, as
amended,
       that, in December 2025, you entered into an in-licensing agreement with
Sermonix
       Pharmaceuticals, Inc. and that, pursuant to that agreement, you assumed
the obligation
       for the ongoing phase 3 trial for lasofoxifene in the licensed
territories; you assumed
       Sermonix   s agreements with third parties, including contract
manufacturers that have
       been supplying drug substances and drug products; and you are required
to make
       payments to Sermonix   s third party service providers. Please tell us
whether you will be
       providing the Sermonix financial statements. If you will not be
providing them, please
       tell us why.
 February 11, 2026
Page 2

        We remind you that the company and its management are responsible for
the accuracy
and adequacy of their disclosures, notwithstanding any review, comments, action
or absence of
action by the staff.

       Refer to Rules 460 and 461 regarding requests for acceleration. Please
allow adequate
time for us to review any amendment prior to the requested effective date of
the registration
statement.

       Please contact Jessica Dickerson at 202-551-8013 or Joe McCann at
202-551-6262 with
any other questions.



                                                           Sincerely,

                                                           Division of
Corporation Finance
                                                           Office of Life
Sciences
cc:   Michael Nordtvedt, Esq.