Sionna Therapeutics, Inc. (SION)
Nasdaq: SION · Pharmaceutical Preparations · Waltham, MA · filing with the SEC since 2024
Who runs Sionna Therapeutics, Inc.
Officers and directors as they report to the SEC on Forms 3, 4 and 5, named as filedChief executive, as filed
Cloonan Michael
President & CEO. First filing Feb 2025, latest Sep 18, 2026, 5 filings in all.
Officers reporting now
5
of 21 people with a filing in the last fifteen months
Directors reporting now
16
22 people on the record since 2025
Officerssales are open-market, Sep 30, 2025 to Sep 30, 2026
| Name | Title as filed | First filing | Latest filing | Sales, 12 months |
|---|---|---|---|---|
| Cloonan Michael | President & CEO | Feb 2025 | Sep 18, 2026 | 7 · $4.4M |
| Ridloff Elena | CFO and CBO | Feb 2025 | Sep 18, 2026 | none |
| Fitzpatrick Jennifer | CLO and Head of Program Mgmt. | Apr 2025 | Sep 18, 2026 | 3 · $1.2M |
| Mckee Charlotte | CMO and Head of R&D | Feb 2025 | Sep 18, 2026 | none |
| Beer Caroline Stark | Chief Business Officer | Oct 2025 | Jan 6, 2026 | none |
Directorssales are open-market, Sep 30, 2025 to Sep 30, 2026
| Name | Role | First filing | Latest filing | Sales, 12 months |
|---|---|---|---|---|
| Kolchinsky Peter | director | Feb 2025 | Sep 21, 2026 | 12 · $1.2M |
| Ra Capital Healthcare Fund LP | director | Feb 2025 | Sep 21, 2026 | none |
| Ra Capital Management, L.P. | director | Feb 2025 | Sep 21, 2026 | 26 · $27.3M |
| Ra Capital Nexus Fund III, L.P. | director | Feb 2025 | Sep 21, 2026 | 8 · $14.8M |
| Ra Capital Nexus Fund, L.P. | director | Feb 2025 | Sep 21, 2026 | none |
| Shah Rajeev M. | director | Feb 2025 | Sep 21, 2026 | none |
| Orbimed Advisors LLC | director | Feb 2025 | Jul 9, 2026 | 13 · $48.9M |
| Orbimed Capital Gp Viii LLC | director | Feb 2025 | Jul 9, 2026 | 7 · $6.8M |
| Thompson Peter A. | director | Feb 2025 | Jul 9, 2026 | 20 · $55.7M |
| Booth Bruce | director | Feb 2025 | Jun 18, 2026 | 48 · $20.1M |
| Clancy Paul J | director | Feb 2025 | Jun 18, 2026 | none |
| Fleming Harold Edward | director | Feb 2025 | Jun 18, 2026 | none |
| Resnick Joshua | director | Feb 2025 | Jun 18, 2026 | none |
| Ruddy Marcella K. | director | Feb 2025 | Jun 18, 2026 | none |
| Stelzer Laurie | director | Feb 2025 | Jun 18, 2026 | none |
| Viney Joanne L. | director | Feb 2025 | Jun 18, 2026 | none |
Owners of more than 10% of a classsales are open-market, Sep 30, 2025 to Sep 30, 2026
| Name | Role | First filing | Latest filing | Sales, 12 months |
|---|---|---|---|---|
| Coulter James G | 10% owner | Feb 2025 | Jan 26, 2026 | none |
| Tpg Gp A, LLC | 10% owner | Feb 2025 | Jan 26, 2026 | none |
| Winkelried Jon | 10% owner | Feb 2025 | Jan 26, 2026 | 1 · $10.0M |
Earlier names on the record7, newest filing first
Atlas Venture Associates Opportunity II, LLC · 10% owner · last filing Feb 2025Atlas Venture Associates Opportunity II, LP · 10% owner · last filing Feb 2025Atlas Venture Associates Xi, L.P. · 10% owner · last filing Feb 2025Atlas Venture Associates Xi, LLC · 10% owner · last filing Feb 2025Atlas Venture Fund Xi, L.P. · 10% owner · last filing Feb 2025Atlas Venture Opportunity Fund II, L.P. · 10% owner · last filing Feb 2025Iancovici Lucian · director · last filing Feb 2025
A person is listed as reporting now after a filing in the last fifteen months. The record shows when someone last filed; it does not say why they stopped. Each name links to the filings on sec.gov.