SEC Form 4 · accession 0001193125-26-355721
Korsana Biosciences, Inc. · KRSA
Statement of changes in beneficial ownership, as filed. Original on EDGAR ↗
Reporting owner
Rhonda M. Chicko
Officer — Chief Financial Officer
Period of report
Aug 14, 2026
Accepted (ET)
Aug 18, 2026 · 5:27 pm EDT
Rule 10b5-1 plan
box not checked
Issuer CIK
0001755237
Table I — non-derivative securities
| Security | Date | Code | Shares | Price | A/D | Owned after | D/I | Nature of ownership |
|---|---|---|---|---|---|---|---|---|
| Common Stock, no par value | Aug 14, 2026 | M | 25,000 | $2.355 | A | 25,018 | D |
Table II — derivative securities
| Security | Conv. / exercise price | Date | Code | Shares | A/D | Exercisable | Expires | Underlying | Underlying shares | Owned after | D/I |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Option to PurchaseF1 | $2.355 | Aug 14, 2026 | M | 25,000 | D | — | Aug 6, 2035 | Common Stock | 25,000 | 0 | D |
Explanation of responses
- F1The Reporting Person was granted an option on August 7, 2025 to purchase up to 25,000 shares of the Corporation's common stock pursuant to the Issuer's 2019 Equity Incentive Plan. These 25,000 shares provided for vesting as follows: (i) 8,750 shares became immediately exercisable, and (ii) the remaining 16,250 shares were to vest ratably in monthly installments commencing August 31, 2025 and ending on February 28, 2028, provided that the Reporting Person remained as a consultant or employee of Cyclerion Therapeutics, Inc. on such applicable vesting date, subject to certain exemptions. On July 17, 2026, the Issuer's Board of Directors elected to accelerate in full the vesting of all then unvested options for the Reporting Person. The Reporting Person exercised the option in full on August 14, 2026 and paid for the exercise by means of a cash payment to the Issuer for the full purchase price.