Welcome to our dedicated page for Korro Bio SEC filings (Ticker: KRRO), a comprehensive resource for investors and traders seeking official regulatory documents including 10-K annual reports, 10-Q quarterly earnings, 8-K material events, and insider trading forms.
Korro Bio, Inc. filings document the regulatory record of a biopharmaceutical company developing RNA-editing genetic medicines through its OPERA® platform. Its 8-K reports disclose operating and financial results, corporate presentations, clinical and regulatory program updates, capital-structure activity, and material events tied to its RNA-editing pipeline.
The company’s filings also cover proxy governance, executive compensation, equity incentive and inducement arrangements, employment agreements, and material collaboration and license agreements. Program-related disclosures focus on KRRO-121, hyperammonemia in urea cycle disorders and hepatic encephalopathy, GalNAc-conjugated oligonucleotide research, alpha-1 antitrypsin deficiency, risk factors, and the financing and governance framework supporting Korro Bio’s development-stage operations.
Korro Bio, Inc. describes its strategy to develop RNA editing medicines for rare and common diseases using its OPERA platform. The company’s lead candidate, KRRO-121, targets hyperammonemia in urea cycle disorders and hepatic encephalopathy, with a first-in-human enabling filing anticipated in the second half of 2026.
Korro is also advancing a next‑generation GalNAc‑conjugated program for alpha‑1 antitrypsin deficiency with development candidate nomination expected in the second quarter of 2026. Additional longevity, liver health and ALS programs, together with a paused Novo Nordisk collaboration, are supported by a cash runway into the second half of 2028.
Korro Bio reported full-year 2025 results showing progress in its RNA-editing pipeline alongside higher losses. Collaboration revenue rose to $6.4 million from $2.3 million in 2024, while research and development expenses grew slightly to $65.6 million and general and administrative costs declined to $28.2 million.
The company recorded $30.9 million of non-cash long-lived asset impairment charges and $3.6 million in restructuring charges tied to 2025 workforce reductions, driving net loss to $117.3 million versus $83.6 million in 2024. Cash, cash equivalents and marketable securities were $85.2 million as of December 31, 2025, and an oversubscribed $85 million private placement completed in March 2026 is expected to fund operations into the second half of 2028.
Operationally, Korro nominated KRRO-121 as a development candidate for hyperammonemia in urea cycle disorders and hepatic encephalopathy, advanced its GalNAc-conjugated alpha-1 antitrypsin deficiency program with plans to nominate a candidate in the second quarter of 2026, and continued preclinical work in longevity, liver health, and ALS.
Korro Bio, Inc. Schedule 13G: Point72 group reports beneficial ownership of 816,885 shares (5.7%) as of March 10, 2026.
The filing lists shared voting and dispositive power across affiliated entities and individuals, with holdings shown by reporting persons including Point72 Asset Management (540,054 shares) and Point72 Biotech Private Investments, LLC (276,831 shares). The reporting persons filed jointly under a Joint Filing Agreement.
Korro Bio, Inc. entered into a subscription agreement for an oversubscribed private placement expected to deliver approximately $85.0 million in gross proceeds. The company will sell 4,501,928 shares of common stock at $11.11 per share and pre-funded warrants to purchase 3,148,836 shares at $11.109 per warrant, with a $0.001 exercise price.
The financing, led by Venrock Healthcare Capital Partners with multiple new and existing institutional investors, together with Korro’s preliminary unaudited $85.2 million in cash, cash equivalents and marketable securities as of December 31, 2025, is expected to extend the company’s cash runway into the second half of 2028. Proceeds are intended to advance Korro’s RNA editing pipeline, including clinical data for KRRO-121 in urea cycle disorders, its GalNAc-conjugated alpha-1 antitrypsin deficiency program, and a longevity and liver health program targeting the AMPKγ1 pathway, with the balance for working capital and general corporate purposes.
Point72-affiliated entities filed an amended Schedule 13G reporting a 2.9% passive stake in Korro Bio, Inc. common stock. As of the close of business on December 31, 2025, Point72 Biotech Private Investments, LLC, Differentiated Ventures Investments, LLC, 72 Investment Holdings, LLC and Steven A. Cohen are each reported as beneficial owners of 276,831 shares of Korro Bio common stock, representing 2.9% of the outstanding class. Point72 Asset Management, L.P. and Point72 Capital Advisors, Inc. report no direct holdings, though the filing describes their roles in managing and controlling affiliated entities. The signatories certify that the securities were not acquired and are not held for the purpose of changing or influencing control of Korro Bio.
Driehaus Capital Management LLC has amended its ownership report for Korro Bio, Inc., stating that it now beneficially owns 0 shares of Korro Bio common stock, representing 0% of the class as of 12/31/2025. The filer confirms it holds no sole or shared voting or dispositive power over any Korro Bio shares and notes this is an exit filing indicating ownership of 5 percent or less of the company’s common stock.
Nantahala Capital Management, LLC and its principals reported a significant ownership stake in Korro Bio, Inc. As of December 31, 2025, they may be deemed to beneficially own 600,000 shares of Korro Bio common stock, representing 6.37% of the outstanding shares.
The shares are held by funds and separately managed accounts under Nantahala’s control, with Nantahala, Wilmot B. Harkey, and Daniel Mack sharing voting and dispositive power over all 600,000 shares. They state that the position is held in the ordinary course of business and not for the purpose of changing or influencing control of Korro Bio.
FMR LLC and Abigail P. Johnson report beneficial ownership of 37,857 shares of Korro Bio Inc. common stock, representing 0.4% of the outstanding class as of the event date of December 31, 2025.
FMR LLC has sole voting power over 33,257 shares and sole dispositive power over 37,857 shares. Abigail P. Johnson reports sole dispositive power over the same 37,857 shares, with no voting power. The filing states the securities were acquired and are held in the ordinary course of business and not for the purpose of changing or influencing control of Korro Bio. One or more other persons may receive dividends or sale proceeds from these shares, but no such person holds more than five percent of the common stock.
Korro Bio, Inc. reported that President and CEO Ram Aiyar received new equity awards on February 2, 2026. He was granted 40,000 shares of common stock through restricted stock units under the 2023 Stock Option and Incentive Plan, vesting 50% on August 3, 2026 and 50% on February 1, 2027, subject to continued service.
He was also granted a stock option for 80,000 shares of common stock at an exercise price of $13.05, vesting in 48 equal monthly installments starting February 2, 2026 and expiring February 1, 2036. Separately, 4,613 common shares are held indirectly by The Ram Aiyar Irrevocable Trust, for which he serves as trustee and disclaims full beneficial ownership.
Korro Bio, Inc. reported that its Chief Scientific Officer, Vincent Loic A, received a grant of stock options on February 2, 2026. The award covers 35,000 stock options with an exercise price of $13.05 per share for Korro Bio common stock.
The options vest in 48 equal monthly installments starting on February 2, 2026, and each monthly vesting is conditioned on the executive’s continued service on that date. After this grant, the officer beneficially owns 35,000 derivative securities directly.