Welcome to our dedicated page for NKGen Biotech SEC filings (Ticker: NKGN), 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.
NKGen Biotech filings document a clinical-stage biotechnology issuer with common stock and warrants quoted on the OTC Expert Market and a capital structure that includes warrant rights and secured debt arrangements. Recent Form 8-K reports focus on material definitive agreements, including secured promissory notes, amendments to loan documents, secured convertible loan agreements and forward purchase agreement amendments involving the company and NKGen Operating Biotech, Inc.
The filings also identify NKGen as an emerging growth company and record corporate history tied to its former name, Graf Acquisition Corp. IV. Its regulatory documents provide formal disclosure of financing terms, subsidiary obligations, warrant exercise economics, governance status and market-quotation information for NKGN securities.
NKGen Biotech, Inc. amended its secured convertible loan with AlpineBrook Capital to add a new $607,200 secured convertible note, providing $552,000 in net proceeds. The note is convertible into common stock at $0.08 per share and is paired with additional equity incentives for the lender.
The company increased the consideration shares under the loan to 12,009,780 common shares, to be issued over 25 months. It also issued a new warrant allowing AlpineBrook to buy common stock based on three times the outstanding principal at a $0.08 exercise price, subject to a 9.99% beneficial ownership cap and anti-dilution protections. A voting agreement commits key holders to support increasing authorized shares to accommodate shares from these notes and warrants.
NKGen Biotech, Inc. entered into a secured convertible loan agreement with AlpineBrook Capital for a $39,922,134.22 one-year convertible loan bearing 12% annual interest. The lender may convert principal and interest into common stock at $0.08 per share, subject to a 9.99% beneficial ownership cap and pricing anti-dilution adjustments.
NKGen also issued a warrant with a $0.08 exercise price for additional shares based on the note principal, plus 11,807,380 consideration shares over five installments. The loan is secured by substantially all personal and intellectual property assets and a pledged 65% equity interest in NKGen Biotech Korea Co., Ltd.
An Investor Rights Agreement grants the lender registration rights, preemptive rights on future financings, extensive protective provisions over major corporate actions, and the right to designate up to five directors, with the board size capped at nine. A Voting Agreement supports increasing authorized shares to cover the note, warrant and consideration shares.
NKGen Biotech, Inc. entered into a fourth amendment to its secured promissory note with AlpineBrook Capital GP I Limited on February 20, 2026. This amendment provides an additional $343,000 in funding, called the Fifth Additional New Loan.
Following this change, the principal amount outstanding under the note increased to $27,101,106. The amendment also clarifies that interest on the new $343,000 loan begins accruing from February 20, 2026, the date the additional funding was provided.
NKGen Biotech, Inc. entered into a third amendment to its secured promissory note with AlpineBrook Capital GP I Limited on January 30, 2026. The amendment provides an additional $251,000 in loan funding, increasing the note’s principal balance to $26,758,106.
The amendment also clarifies that interest on this new loan tranche, referred to as the Fourth Additional New Loan, begins accruing from January 30, 2026, the funding date. This creates an additional direct financial obligation for NKGen and its subsidiary NKGen Operating Biotech, Inc.
NKGen Biotech, Inc. filed an 8-K describing two financing-related amendments. On January 20, 2026, the company and Meteora-affiliated counterparties signed an eighth amendment to their forward purchase agreement for OTC equity prepaid forward transactions, extending the agreement’s Valuation Date to December 31, 2026 while keeping all other terms the same.
On January 23, 2026, NKGen Biotech, Inc. and NKGen Operating Biotech, Inc. entered into a second amendment to their secured promissory note with AlpineBrook Capital GP I Limited, providing an additional $372,000 loan. This increased the note’s principal amount to $26,507,106 and confirmed that interest on this third additional loan accrues from January 23, 2026.
NKGen Biotech, Inc. reports first‑quarter 2025 results showing an accounting profit but very limited liquidity and a continued going concern warning. For the three months ended March 31, 2025, the company generated net income of $15.4 million, driven mainly by a $21.6 million gain from changes in fair value of financial instruments, while its core business recorded a loss from operations of $4.7 million as research and development and general and administrative costs totaled $4.7 million.
On the balance sheet, NKGen had cash and cash equivalents of $6 thousand, total assets of $15.8 million, and total liabilities of $66.2 million as of March 31, 2025, resulting in a stockholders’ deficit of $50.3 million. Working capital was a deficit of $41.5 million. Management states there is substantial doubt about the company’s ability to continue as a going concern without additional near‑term financing and notes that potential measures include cost reductions or even ceasing operations.
The company also discloses that its securities were delisted from The Nasdaq Global Market in March 2025 and now trade on OTC venues, including the OTC Expert Market, while it continues as a clinical‑stage developer of NK cell therapies using its proprietary SNK platform.
NKGen Biotech, Inc. reported that on January 12, 2026, it and its subsidiary NKGen Operating Biotech, Inc. amended an existing secured promissory note with AlpineBrook Capital GP I Limited. The amendment provides an additional $295,000 in funding, called the Second Additional New Loan, increasing the total principal amount of the note to $26,135,106.
The amendment also specifies how interest accrues on the different portions of the debt. Interest on $25,840,106 of principal continues to accrue from January 5, 2026, the date of the original note, while interest on the new $295,000 portion begins accruing from January 12, 2026, the date the amendment was executed.
NKGen Biotech, Inc. entered into a new secured promissory note with AlpineBrook Capital GP I Limited on January 5, 2026. The note has an original principal amount of $25,840,106, bears interest at 12% per year, and initially matures two months after issuance, with any extension at the lender’s discretion. It formalizes earlier undocumented cash advances totaling $25,540,106 and adds a new $300,000 advance.
The note cannot be prepaid before maturity without lender consent and includes a “most favored nation” clause requiring NKGen to match more favorable terms granted in future debt or equity financings. A Change of Control triggers cash repayment of principal and interest plus a cash premium equal to 20% of outstanding principal, while events of default increase the interest rate to 24% per year. The lender receives security interests over substantially all U.S. personal property of the borrowers, certain U.S. real property, and Korean collateral related to NKGen Biotech Korea, alongside restrictive covenants limiting additional debt, liens, and equity issuances.