TPG GP A, LLC - 22 Jan 2026 Form 4 Insider Report for Sionna Therapeutics, Inc. (SION)

Reporting relationship: 10%+ Owner
Issuer ticker: SION
Reported as of: 22 Jan 2026
Net transaction value: -$10,000,000
SEC form: 4
Accepted by SEC: 26 Jan 2026, 17:24:52 UTC
Prior SEC filing: 30 Dec 2025
Next SEC filing: 02 Feb 2026
Source filing: View source filing
Reporting owner signature: /s/ Martin Davidson, Chief Accounting Officer, TPG GP A, LLC (5)

Key filing fact

TPG GP A, LLC filed Form 4 for Sionna Therapeutics, Inc. (SION) on 26 Jan 2026.

Key facts

This page summarizes TPG GP A, LLC's Form 4 filing for Sionna Therapeutics, Inc. (SION).
1 reported transaction and 0 derivative rows are listed below.
Accepted by SEC: 26 Jan 2026, 17:24.

Change

Previous filing in this sequence was filed on 30 Dec 2025.
Current net transaction value: -$10,000,000.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (3)

CIK 0001903793 Primary reporting owner

TPG GP A, LLC

Relationship: 10%+ Owner
Address: C/O TPG INC., 301 COMMERCE STREET, SUITE 3300, FORT WORTH
Signature: /s/ Martin Davidson, Chief Accounting Officer, TPG GP A, LLC (5)
Signature date: 26 Jan 2026

CIK 0001099776

COULTER JAMES G

Relationship: 10%+ Owner
Address: C/O TPG GLOBAL, LLC, 301 COMMERCE STREET, SUITE 3300, FORT WORTH
Signature: /s/ Gerald Neugebauer, on behalf of James G. Coulter (5) (6)
Signature date: 26 Jan 2026

CIK 0001366946

WINKELRIED JON

Relationship: 10%+ Owner
Address: C/O TPG GLOBAL, LLC, 301 COMMERCE STREET, SUITE 3300, FORT WORTH
Signature: /s/ Gerald Neugebauer, on behalf of Jon Winkelried (5) (6)
Signature date: 26 Jan 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

SION transaction

Common Stock

Sale

Transaction value: $10,000,000
Shares: -250,000
Change %: -3.7%
Price: $40.00
Shares after: 6,494,962
Date: 22 Jan 2026
Ownership: See Explanation of Responses
Footnotes: F1, F2, F3, F4

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 4 footnotes

Footnote F1

Each of James G. Coulter and Jon Winkelried own entities that control TPG GP A, LLC (together with Messrs. Coulter and Winkelried, the "Reporting Persons"), which exercises direct or indirect control over entities that collectively hold 100% of the shares of Class B common stock (which represents a majority of the combined voting power of the common stock) of TPG Inc., which is the sole member of TPG GPCo, LLC, which is the sole member of TPG Holdings II-A, LLC, which is the general partner of TPG Operating Group II, L.P., which is the sole member of TPG Holdings I-A, LLC, which is the general partner of TPG Operating Group I, L.P., which is the sole member of The Rise Fund GenPar Advisors, LLC, which is the general partner of The Rise Fund GenPar, L.P., which is the managing member of The Rise Fund SPV GP, LLC.

Footnote F2

The Rise Fund SPV GP, LLC is the general partner of each of The Rise Fund Sling, L.P., which directly holds 5,340,931 shares of Common Stock ("Common Stock") of Sionna Therapeutics, Inc. (the "Issuer"), and The Rise Fund Sling II, L.P. (together with The Rise Fund Sling, L.P., the "TPG Funds"), which directly holds 1,154,031 shares of Common Stock.

Footnote F3

Because of the relationship between the Reporting Persons and the TPG Funds, the Reporting Persons may be deemed to beneficially own the securities reported herein to the extent of the greater of their respective direct or indirect pecuniary interests in the profits or capital accounts of the TPG Funds. Each of the TPG Funds and each Reporting Person disclaims beneficial ownership of the securities reported herein, except to the extent of such TPG Fund's or such Reporting Person's pecuniary interest therein, if any

Footnote F4

Pursuant to Rule 16a-1(a)(4) under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), this filing shall not be deemed an admission that the Reporting Persons are, for purposes of Section 16 of the Exchange Act or otherwise, the beneficial owners of any equity securities in excess of their respective pecuniary interests.

SEC remarks

(5) The Reporting Persons are jointly filing this Form 4 pursuant to Rule 16a-3(j) under the Exchange Act. (6) Gerald Neugebauer is signing on behalf of Messrs. Coulter and Winkelried pursuant to authorization and designation letters dated January 10, 2024, which were previously filed with the Securities and Exchange Commission.