Sionna Therapeutics, Inc. (SION)
Nasdaq: SION · Pharmaceutical Preparations · Waltham, MA · filing with the SEC since 2024
Who owns Sionna Therapeutics, Inc.
As filed with the SECHolders of 5% or more
6
Tpg Gp A, LLC holds 15.2% of Common Stock, par value $0.001 per share, as its SCHEDULE 13D filed Feb 18, 2025 says.
Directors and officers
21
report now, of 22 people on the record since 2025. Their holdings as a group are not read here.
Institutions as a whole
n/a
The record does not read the share held by managers that file Form 13F, so none is printed and no split of the rest is estimated. What it holds is the 6 named at left.
Holders of 5% or moreshare of the class, as filed
Tpg Gp A, LLC
SCHEDULE 13D · filed Feb 18, 2025 · Common Stock, par value $0.001 per share
RA Capital Management, L.P.
SCHEDULE 13D/A · filed Sep 21, 2026 · Common Stock, $0.001 par value per share · 22.6% in Nov 7, 2025
Viking Global Investors LP
SCHEDULE 13G/A · filed May 15, 2026 · Common Stock, $0.001 par value per share · 6.7% in Feb 14, 2025
Orbimed Advisors LLC
SCHEDULE 13D/A · filed Apr 20, 2026 · Common Stock · 8.4% in Feb 13, 2025
Enavate Sciences GP, LLC
SCHEDULE 13D · filed Feb 18, 2025 · Common Stock, $0.001 par value per share
Atlas Venture Fund XI, L.P.
SCHEDULE 13D/A · filed Oct 20, 2025 · Common Stock · 6.5% in Feb 18, 2025
Qatar Investment Authority
SCHEDULE 13G/A · filed May 12, 2026 · Common Stock SH · reported falling below 5%, from 5% in Jun 16, 2025
JPMorgan Chase & Co.
SCHEDULE 13G/A · filed Oct 31, 2025 · Common Stock, $0.001 par value per share · reported falling below 5%, from 5% in Jul 30, 2025
What SION reports owning in othersstakes of 5% or more, and other ties
Sionna Therapeutics, Inc. reports no stake in another company in the record.
Insider tradesForm 4
142sales
0purchases
96sales on a scheduled plan
9people selling
$180Msold, in dollars
$0bought, in dollars
Open-market trades on Form 4 from Sep 30, 2025 to Sep 30, 2026. A scheduled plan is a selling program set in advance under SEC rule 10b5-1. The trades are listed as filed and do not feed the grade.
By calendar yearSoldBought
2026 runs to Sep 30, 2026. Dollars as filed, summed by the transaction date.
People who traded in the window10 of 31 on the roster
| Person | Role as filed | Sales | Sold | On a plan | Buys | Bought |
|---|---|---|---|---|---|---|
| Thompson Peter A. | director | 20 | $55.7M | 20 | 0 | $0 |
| Orbimed Advisors LLC | director | 13 | $48.9M | 13 | 0 | $0 |
| Ra Capital Management, L.P. | director | 26 | $27.3M | 0 | 0 | $0 |
| Booth Bruce | director | 48 | $20.1M | 48 | 0 | $0 |
| Ra Capital Nexus Fund III, L.P. | director | 8 | $14.8M | 0 | 0 | $0 |
| Winkelried Jon | 10% owner | 1 | $10.0M | 0 | 0 | $0 |
| Orbimed Capital Gp Viii LLC | director | 7 | $6.8M | 7 | 0 | $0 |
| Cloonan Michael | President & CEO | 7 | $4.4M | 7 | 0 | $0 |
| Fitzpatrick Jennifer | CLO and Head of Program Mgmt. | 3 | $1.2M | 3 | 0 | $0 |
| Kolchinsky Peter | director | 12 | $1.2M | 0 | 0 | $0 |