Form4insider filings, from the source

SEC Form 4 · accession 0001231919-26-001201

Sionna Therapeutics, Inc. · SION

Statement of changes in beneficial ownership, as filed. Original on EDGAR ↗

Reporting owners
RA CAPITAL MANAGEMENT, L.P.
Director · 10% Owner
Peter Kolchinsky
Director · 10% Owner
Rajeev M. Shah
Director · 10% Owner
Period of report
Sep 17, 2026
Accepted (ET)
Sep 21, 2026 · 6:56 pm EDT
Rule 10b5-1 plan
box not checked
Issuer CIK
0002036042

Table I — non-derivative securities

SecurityDateCodeSharesPriceA/DOwned afterD/INature of ownership
Common StockF1,F2Sep 17, 2026S3,415,011$6.32D3,482,612ISee footnotes
Common StockF3,F1,F2Sep 17, 2026S33,800$7.46D3,448,812ISee footnotes
Common StockF1,F4holding———650,307ISee footnotes
Common StockF1,F5holding———2,198,082ISee footnotes
Common StockF1,F6holding———159,033ISee footnotes

Table II — derivative securities

No Table II lines on this filing.

Explanation of responses

Remarks

Dr. Joshua Resnick, a Partner of the Adviser, serves on the Issuer's board of directors.