Business Description

1. Nature of Business PepGen Inc., hereinafter referred to as PepGen or the Company, is a clinical-stage biotechnology company advancing the next generation of oligonucleotide therapeutics with the goal of transforming the treatment of severe neuromuscular and neurologic diseases. The Company's principal offices are located in Boston, Massachusetts. The Company was initially formed as PepGen Limited on January 25, 2018, in the United Kingdom, or the U.K. On November 9, 2020, PepGen Limited completed a corporate reorganization, or the Reorganization. As part of the Reorganization, PepGen Limited formed PepGen, a Delaware corporation with nominal assets and liabilities, for the purpose of consummating the Reorganization. In connection with the Reorganization, the existing stockholders of PepGen Limited exchanged each of its classes of shares of PepGen Limited for the same number and class of common stock of PepGen on a one-to-one basis. The newly issued stock of PepGen had substantially identical rights to the exchanged shares of PepGen Limited. As a result of the exchange, PepGen became the sole stockholder of PepGen Limited. Upon the completion of the Reorganization on November 23, 2020, the historical financial statements of PepGen Limited became the historical financial statements of PepGen as the Reorganization was deemed to be between entities under common control. PepGen Limited was dissolved on December 10, 2024. Liquidity Since inception, the Company has not generated any revenue from product sales or other sources and has incurred significant operating losses and negative cash flows from operations. The Company’s primary uses of cash, cash equivalents, and marketable securities to date have been funding research and development activities, business planning, establishing and maintaining the Company’s intellectual property portfolio, hiring personnel, leasing premises and associated capital expenditures, raising capital, and providing general and administrative support for these operations. As of December 31, 2025, the Company had an accumulated deficit of $ 361.1 million. To date, the Company has funded operations primarily through private placements of convertible preferred stock, the sale of shares of common stock in its initial public offering, or IPO, the sale of shares of common stock under its At-the-Market Equity Offering Sales Agreement, or Sales Agreement, with Stifel, Nicolaus & Company, Incorporated, or Stifel, and through the sale of shares of common stock in follow-on public offerings in February 2024, referred to as the 2024 Offering, and in September 2025, referred to as the 2025 Offering. As of December 31, 2025, the Company had cash, cash equivalents, and marketable securities of $ 148.5 million. The Company filed a shelf registration statement on Form S-3 with the United States Securities and Exchange Commission, or SEC, which covers the offering, issuance and sale of an amount up to $ 300.0 million in the aggregate of shares of common stock, preferred stock, debt securities, warrants, and/or units or any combination thereof, which was declared effective on June 16, 2023. On August 8, 2023, the Company filed a prospectus supplement and entered into the Sales Agreement with Stifel, as sales agent, which provides for the issuance and sale by the Company of up to $ 100.0 million of shares of common stock from time to time in “at-the-market” offerings. Stifel is entitled to receive a commission of up to 3.0 % of gross proceeds from sales under the Sales Agreement. On February 5, 2024, the Company sold 1,000,000 shares of common stock at a price of $ 10.00 per share under the Sales Agreement, resulting in net proceeds of $ 9.9 million. On February 9, 2024, the Company sold 7,530,000 shares of common stock in the 2024 Offering, pursuant to an underwriting agreement with Leerink Partners LLC dated as of February 6, 2024, at a price of $ 10.635 per share, resulting in net proceeds of $ 76.4 million after deducting underwriting fees and offering costs of $ 3.7 million. Net proceeds from sales in 2024 under the Sales Agreement and 2024 Offering, after deducting underwriters' fees and costs, were $ 86.3 million.…