Michael Cloonan - 15 Oct 2025 Form 4 Insider Report for Sionna Therapeutics, Inc. (SION)

Role
President & CEO, Director
Signature
Jennifer Fitzpatrick, Attorney-in-Fact
Issuer symbol
SION
Transactions as of
15 Oct 2025
Net transactions value
-$634,181
Form type
4
Filing time
17 Oct 2025, 17:11:22 UTC
Previous filing
30 Sep 2025
Next filing
22 Oct 2025
SEC
View on sec.gov

Reporting Owners (1)

Name Relationship Address Signature Signature date CIK
Cloonan Michael President & CEO, Director C/O SIONNA THERAPEUTICS, INC., 21 HICKORY DRIVE, SUITE 500, WALTHAM Jennifer Fitzpatrick, Attorney-in-Fact 17 Oct 2025 0001704336

Transactions Table

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Ownership Footnotes
transaction SION Common Stock Options Exercise $90,275 +14,775 +2.7% $6.11 562,118 15 Oct 2025 Direct F1
transaction SION Common Stock Sale $459,662 -14,775 -2.6% $31.11 547,343 15 Oct 2025 Direct F1, F2
transaction SION Common Stock Options Exercise $62,475 +10,225 +1.9% $6.11 557,568 16 Oct 2025 Direct F1
transaction SION Common Stock Sale $321,691 -10,225 -1.8% $31.46 547,343 16 Oct 2025 Direct F1, F3
transaction SION Common Stock Options Exercise $1,222 +200 +0.04% $6.11 547,543 16 Oct 2025 Direct F1
transaction SION Common Stock Sale $6,800 -200 -0.04% $34.00 547,343 16 Oct 2025 Direct F1

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Underlying Class Amount Exercise Price Ownership Footnotes
transaction SION Non-Qualified Stock Option (right to buy) Options Exercise $0 -14,775 -8.3% $0.000000 163,367 15 Oct 2025 Common Stock 14,775 $6.11 Direct F1, F4
transaction SION Non-Qualified Stock Option (right to buy) Options Exercise $0 -10,225 -6.3% $0.000000 153,142 16 Oct 2025 Common Stock 10,225 $6.11 Direct F1, F4
transaction SION Non-Qualified Stock Option (right to buy) Options Exercise $0 -200 -0.13% $0.000000 152,942 16 Oct 2025 Common Stock 200 $6.11 Direct F1, F4
* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Buy Plan / Sale Plan: These are also open market purchases/sales of shares, but in this case the transaction is part of a trading plan. Rule 10b5-1 allows insiders to setup a trading plan to buy/sell stocks over a certain period of time. Since the purchases/sales are predetermined, this protects the insiders from violating insider trading law.

Transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c).

Explanation of Responses:

Id Content
F1 This transaction was automatically executed pursuant to a Rule 10b5-1 trading plan adopted on May 21, 2025.
F2 The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $31.00 to $31.28, inclusive. The Reporting Person undertakes to provide to the Issuer, any securityholder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price at which the transactions were effected.
F3 The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $31.07 to $31.74, inclusive. The Reporting Person undertakes to provide to the Issuer, any securityholder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price at which the transactions were effected.
F4 The shares underlying this option vest in forty-eight equal monthly installments following February 2, 2022, subject to the Reporting Person's continued service on each such vesting date.