Quick Takeaways
- RA CAPITAL MANAGEMENT, L.P. filed SCHEDULE 13D/A for SIONNA THERAPEUTICS, INC. Common Stock, $0.001 par value per share (SION).
- Disclosed ownership: 23%.
- Date of event: 05 Nov 2025.
RA CAPITAL MANAGEMENT, L.P. - 05 Nov 2025 SCHEDULE 13D/A Report for SIONNA THERAPEUTICS, INC. Common Stock, $0.001 par value per share (SION)
- Filing Manager
- RA CAPITAL MANAGEMENT, L.P.
- Reporting Manager
- RA Capital Management, L.P.
- Symbol
- SION
- Shares outstanding
- 44,565,097 shares
- Disclosed Ownership
- 10,071,712 shares
- Ownership
- 23%
- Form type
- SCHEDULE 13D/A
- Filing time
- 07 Nov 2025, 16:59:24 UTC
- Date of event
- 05 Nov 2025
- Previous filing
- 18 Feb 2025
- SEC
- View on sec.gov
Quoteable Key Fact
"RA CAPITAL MANAGEMENT, L.P. disclosed 23% ownership in SIONNA THERAPEUTICS, INC. Common Stock, $0.001 par value per share (SION) on 05 Nov 2025."
What Changed
- Previous schedule filing date: 18 Feb 2025.
- Current filing was accepted on 07 Nov 2025, 16:59.
Why This Matters
- This page explains what this Schedule 13D/13G filing tells you before manager-level rows.
- You can verify ownership claims directly against the original SEC filing.
Source Evidence
Backed by Schedule 13D/13G
See Original Filing
Beneficial ownership values are sourced from the original SEC Schedule 13D/13G filing.
Reporting Managers (5)
| Name | Ownership | Shares Owned | sole voting power | shared voting power | Signature | Title | CIK |
|---|---|---|---|---|---|---|---|
| RA Capital Management, L.P. | 23% | 10,071,712 | 0 | 10,071,712 | /s/ Peter Kolchinsky | By Peter Kolchinsky, Authorized Signatory | 0001346824 |
| Peter Kolchinsky | 23% | 10,071,712 | 0 | 10,071,712 | /s/ Peter Kolchinsky | Peter Kolchinsky | 0001384859 |
| Rajeev Shah | 23% | 10,071,712 | 0 | 10,071,712 | /s/ Rajeev Shah | Rajeev Shah | 0001619841 |
| RA Capital Healthcare Fund, L.P. | 16% | 6,905,625 | 0 | 6,905,625 | /s/ Peter Kolchinsky | By RA Capital Healthcare Fund GP, LLC, its General Partner, By Peter Kolchinsky, Manager | 0001315082 |
| RA Capital Nexus Fund III, L.P. | 5% | 2,240,708 | 0 | 2,240,708 | /s/ Peter Kolchinsky | By RA Capital Nexus Fund III GP, LLC, its General Partner, By Peter Kolchinsky, Manager | 0001883840 |