SEC Form 4 · accession 0000947871-26-000695
Sionna Therapeutics, Inc. · SION
Statement of changes in beneficial ownership, as filed. Original on EDGAR ↗
Reporting owner
Peter A. Thompson
Director
Period of report
Jul 7, 2026
Accepted (ET)
Jul 9, 2026 · 4:47 pm EDT
Rule 10b5-1 plan
yes — trade under a plan
Issuer CIK
0002036042
Table I — non-derivative securities
| Security | Date | Code | Shares | Price | A/D | Owned after | D/I | Nature of ownership |
|---|---|---|---|---|---|---|---|---|
| Common StockF1,F2,F3 | Jul 7, 2026 | S | 85,918 | $44.86 | D | 2,469,959 | I | See footnotes |
Table II — derivative securities
No Table II lines on this filing.
Explanation of responses
- F1These securities were sold pursuant to a 10b5-1 plan.
- F2These securities are held of record by OrbiMed Private Investments VIII, LP ("OPI VIII"). OrbiMed Capital GP VIII LLC ("GP VIII") is the general partner of OPI VIII and OrbiMed Advisors LLC ("OrbiMed Advisors") is the managing member of GP VIII. By virtue of such relationships, GP VIII and OrbiMed Advisors may be deemed to have voting and investment power with respect to the shares held by OPI VIII and as a result may be deemed to have beneficial ownership of such shares. OrbiMed Advisors exercises investment and voting power through a management committee comprised of Carl L. Gordon, Sven H. Borho, and W. Carter Neild, each of whom disclaims beneficial ownership of the shares held by OPI VIII. The Reporting Person is a member of OrbiMed Advisors.
- F3Each of the Reporting Person, OrbiMed Advisors, and GP VIII disclaims beneficial ownership of the securities reported herein for purposes of Rule 16a-1(a) under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), except to the extent of its pecuniary interest therein, if any. This report shall not be deemed an admission that any such entity or person is a beneficial owner of such securities for purposes of Section 16 of the Exchange Act, or for any other purpose.