SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

(Amendment No. 8)

LeonaBio, Inc.

(Name of Issuer)

Common Stock, $0.0001 par value

(Title of Class of Securities)

04746L203

(CUSIP Number)

Alexander Rakitin
Perceptive Advisors LLC, 51 Astor Place, 10th Floor
New York, NY, 10003
(646) 205-5345

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

08/22/2026

(Date of Event Which Requires Filing of This Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§ 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box. Checkbox not checked

The information required on 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).

SCHEDULE 13D

CUSIP Number(s):

04746L203

Name of reporting person

Perceptive Advisors LLC

Check the appropriate box if a member of a Group (See Instructions)

(a)

(b)

SEC use only

Source of funds (See Instructions)

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

Checkbox checked

Citizenship or place of organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 1,889,403.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 1,889,403.00

Aggregate amount beneficially owned by each reporting person

1,889,403.00

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

Checkbox not checked

Percent of class represented by amount in Row (11)

19.99 %

Type of Reporting Person (See Instructions)

SCHEDULE 13D

CUSIP Number(s):

04746L203

Name of reporting person

Joseph Edelman

Check the appropriate box if a member of a Group (See Instructions)

(a)

(b)

SEC use only

Source of funds (See Instructions)

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

Checkbox checked

Citizenship or place of organization

UNITED STATES

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 1,889,403.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 1,889,403.00

Aggregate amount beneficially owned by each reporting person

1,889,403.00

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

Checkbox not checked

Percent of class represented by amount in Row (11)

19.99 %

Type of Reporting Person (See Instructions)

SCHEDULE 13D

CUSIP Number(s):

04746L203

Name of reporting person

Perceptive Life Sciences Master Fund, Ltd.

Check the appropriate box if a member of a Group (See Instructions)

(a)

(b)

SEC use only

Source of funds (See Instructions)

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

Checkbox checked

Citizenship or place of organization

CAYMAN ISLANDS

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 1,559,647.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 1,559,647.00

Aggregate amount beneficially owned by each reporting person

1,559,647.00

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

Checkbox not checked

Percent of class represented by amount in Row (11)

16.5 %

Type of Reporting Person (See Instructions)

SCHEDULE 13D

CUSIP Number(s):

04746L203

Name of reporting person

Perceptive Xontogeny Venture Fund II, LP

Check the appropriate box if a member of a Group (See Instructions)

(a)

(b)

SEC use only

Source of funds (See Instructions)

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

Checkbox not checked

Citizenship or place of organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 359,837.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 359,837.00

Aggregate amount beneficially owned by each reporting person

359,837.00

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

Checkbox not checked

Percent of class represented by amount in Row (11)

3.8 %

Type of Reporting Person (See Instructions)

SCHEDULE 13D

Item 1.

Security and Issuer

(a)

Title of Class of Securities:

Common Stock, $0.0001 par value

(b)

Name of Issuer:

LeonaBio, Inc.

(c)

Address of Issuer's Principal Executive Offices:

18706 North Creek Parkway, Suite 104, Bothell, WASHINGTON , 98011.

Item 4.

Purpose of Transaction

Item 4 of the Schedule 13D is amended and supplemented as follows: On August 22, 2026, Sermonix notified the Reporting Persons that it will distribute Sermonix Pre-Funded Warrants exercisable for 2,352,932 shares of Common Stock to PXV II pursuant to a distribution of securities to owners of Sermonix's common stock. The distribution is expected to be effective on October 26, 2026. Pursuant to the terms of the Sermonix Pre-Funded Warrants, the pre-funded warrants that will be held by PXV II will not be exerciseable to the extent that such exercise would result in beneficial ownership in excess of 19.99% of the outstanding shares of Common Stock of the Issuer.

Item 5.

Interest in Securities of the Issuer

(a)

Item 5 of the Schedule 13D is amended and supplemented as follows: The information set forth in rows 11 and 13 of the cover pages to this Schedule 13D is incorporated by reference. The percentages set forth in row 13 are based on an aggregate of 9,421,663 shares of Common Stock outstanding, as disclosed by the Issuer in its Quarterly Report on Form 10-Q filed with the SEC on August 14, 2026, and give effect to the exercise of warrants held by the Reporting Persons for an aggregate of 30,081 shares of Common Stock.

(b)

The information set forth in rows 7 through 10 of the cover pages to this Schedule 13D is incorporated by reference. Mr. Edelman holds vested stock options to purchase shares of Common Stock in connection with his service as a director of the Issuer; however, such options are not included in the number of shares beneficially owned by Mr. Edelman or the other Reporting Persons because Mr. Edelman agreed on January 13, 2026 that such options cannot be exercised by Mr. Edelman without providing notice to the Issuer of at least 61 days to the extent that such exercise would result in Mr. Edelman or the other Reporting Persons beneficially owning more than 19.99% of the outstanding shares of Common Stock of the Issuer. Pursuant to the terms of the warrants and pre-funded warrants held by the Master Fund and PXV II, the Reporting Persons may not exercise such warrants or pre-funded warrants to the extent that such exercise would result in beneficial ownership in excess of 19.99% of the outstanding shares of Common Stock of the Issuer. As of the date hereof, the Beneficial Ownership Limitation permits the Master Fund or PXV II to exercise warrants and pre-funded warrants for an aggregate of 30,081 shares of Common Stock.

(c)

None of the Reporting Persons has effected any transaction in shares of Common Stock in the past sixty days.

SIGNATURE

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.

Perceptive Advisors LLC

Signature:	/s/ Joseph Edelman
Name/Title:	Joseph Edelman, Managing Member
Date:	08/25/2026

Joseph Edelman

Signature:	/s/ Joseph Edelman
Name/Title:	Joseph Edelman
Date:	08/25/2026

Perceptive Life Sciences Master Fund, Ltd.

Signature:	/s/ Joseph Edelman
Name/Title:	Joseph Edelman, Managing Member
Date:	08/25/2026

Perceptive Xontogeny Venture Fund II, LP

Signature:	/s/ Joseph Edelman
Name/Title:	Joseph Edelman, Managing Partner
Date:	08/25/2026