Form4insider filings, from the source

Insider holders · CIK 0002036042

Sionna Therapeutics, Inc. · SION

Every insider with a reported Table I holding at this company, ranked by their last-reported share count. A balance is only as fresh as its filing — the report date sits next to every row on purpose. ← Back to activity

InsiderDirect sharesIndirect sharesTotal reportedLast report (ET)From
OrbiMed Capital GP VIII LLCDirector—2,469,9592,469,959Jul 9, 2026 · 4:44 pm EDTForm 4
Peter A. ThompsonDirector—2,469,9592,469,959Jul 9, 2026 · 4:47 pm EDTForm 4
ORBIMED ADVISORS LLCDirector—2,469,9592,469,959Jul 9, 2026 · 4:44 pm EDTForm 4
Michael CloonanPresident & CEO765,393—765,393Sep 18, 2026 · 4:52 pm EDTForm 4
RA Capital Nexus Fund III, L.P.Director—159,033159,033Sep 21, 2026 · 6:56 pm EDTForm 4
RA Capital Nexus Fund, L.P.Director—159,033159,033Sep 21, 2026 · 6:56 pm EDTForm 4
Rajeev M. ShahDirector—159,033159,033Sep 21, 2026 · 6:56 pm EDTForm 4
Peter KolchinskyDirector—159,033159,033Sep 21, 2026 · 6:56 pm EDTForm 4
RA CAPITAL MANAGEMENT, L.P.Director—159,033159,033Sep 21, 2026 · 6:56 pm EDTForm 4
RA Capital Healthcare Fund LPDirector—159,033159,033Sep 21, 2026 · 6:56 pm EDTForm 4
Elena RidloffCFO and CBO133,069—133,069Sep 18, 2026 · 4:59 pm EDTForm 4
Charlotte McKeeCMO and Head of R&D128,415—128,415Sep 18, 2026 · 4:58 pm EDTForm 4
Jennifer FitzpatrickCLO and Head of Program Mgmt.56,265—56,265Sep 18, 2026 · 4:56 pm EDTForm 4

Balances come from each insider’s most recent filing that reports a Table I holding; an insider who left the company years ago still appears with their last-known figure and its date. Indirect totals collapse multiple vehicles (trusts, LLCs) into one number — open the filing for the breakdown. Shares as filed, not split-adjusted.