Seaport Therapeutics, Inc.

Previous wording

The success of our business depends primarily upon our ability to identify, develop, and commercialize product candidates based on our Glyph platform. We do not know whether we will be able to develop any product candidates that succeed through clinical development or to develop products of commercial value. We have no products approved for commercial sale and have not generated any revenue from product sales or collaboration arrangements to date. We will continue to incur significant research and development and other expenses related to our preclinical and clinical development and ongoing operations. As a result, we are not profitable and have incurred losses in each period since our inception. Net losses and negative cash flows have had, and will continue to have, an adverse effect on our stockholders’ equity and working capital. Our net losses totaled $25.4 million and $13.1 million for the three months ended March 31, 2026 and 2025, respectively. As of March 31, 2026, we have not yet generated product or collaboration revenue and had an accumulated deficit of $139.5 million. We expect to continue to incur significant losses for the foreseeable future, and we expect these losses to increase as we continue our research and development of, and seek regulatory approvals for, our product candidates. The success of our product candidates will depend on several factors, including the following:

Current wording

The success of our business depends primarily upon our ability to identify, develop, and commercialize product candidates based on our Glyph platform. We do not know whether we will be able to develop any product candidates that succeed through clinical development or to develop products of commercial value. We have no products approved for commercial sale and have not generated any revenue from product sales or collaboration arrangements to date. We will continue to incur significant research and development and other expenses related to our preclinical and clinical development and ongoing operations. As a result, we are not profitable and have incurred losses in each period since our inception. Net losses and negative cash flows have had, and will continue to have, an adverse effect on our stockholders’ equity and working capital. Our net losses totaled $88.0 million and $28.2 million for the six months ended June 30, 2026 and 2025, respectively. As of June 30, 2026, we have not yet generated product or collaboration revenue and had an accumulated deficit of $202.1 million. We expect to continue to incur significant losses for the foreseeable future, and we expect these losses to increase as we continue our research and development of, and seek regulatory approvals for, our product candidates. The success of our product candidates will depend on several factors, including the following:

Previous wording

As of March 31, 2026, we had $212.6 million of cash, cash equivalents and investments. Based upon our current operating plan, we believe that our existing cash, cash equivalents, and investments, together with the net proceeds from our IPO, will enable us to fund our operating expenses and capital expenditure requirements into 2029. We have based this estimate on assumptions that may prove to be wrong, and we could utilize our available capital resources sooner than we expect. We may also raise additional financing on an opportunistic basis in the future. For example, we may seek additional capital due to favorable market conditions or strategic considerations even if we believe we have sufficient funds for our current or future operating plans. Attempting to secure additional financing may divert our management from our day-to-day activities, which may adversely affect our ability to develop our product candidates. Our future capital requirements will depend on many factors, including but not limited to:

Current wording

As of June 30, 2026, we had $427.3 million of cash, cash equivalents and investments. Based upon our current operating plan, we believe that our existing cash, cash equivalents, and investments, will enable us to fund our operating expenses and capital expenditure requirements into 2029. We have based this estimate on assumptions that may prove to be wrong, and we could utilize our available capital resources sooner than we expect. We may also raise additional financing on an opportunistic basis in the future. For example, we may seek additional capital due to favorable market conditions or strategic considerations even if we believe we have sufficient funds for our current or future operating plans. Attempting to secure additional financing may divert our management from our day-to-day activities, which may adversely affect our ability to develop our product candidates. Our future capital requirements will depend on many factors, including but not limited to:

Previous wording

We have never commercialized a product, and even if any of our product candidates are approved by the appropriate regulatory authorities for marketing and sale, it may nonetheless fail to achieve sufficient market acceptance by physicians, patients, third-party payors and others in the medical community. The commercial success of any of our product candidates will depend significantly on the broad adoption and use of the resulting product by these individuals and organizations for approved indications. For example, Glyph2BLSDTM, in development for the treatment of depressive disorders, including treatment-resistant depression, or TRD, post-traumatic stress disorder, or PTSD, and headache disorders, is a Glyphed oral prodrug of the non-hallucinogenic neuroplastogen, 2-bromo-LSD. There has been recent interest in psychedelics in part because of their potential to demonstrate therapeutic effects in neuropsychiatric disorders. Although Glyph2BLSD is not a psychedelic, there is a risk that it will be viewed as such by investors and the public, or could be classified as such by regulatory authorities based on its final structure. Treatments containing controlled substances or drugs that have similar effects or characteristics of controlled substances may generate public controversy or unfavorable views, which could lead to delays in, and increased expenses for, and limit or restrict the introduction and marketing of such types of therapeutic candidates. For more information on controlled substances, see subsection titled “—Certain of our product candidates may be regulated as controlled substances, the making, use, sale, importation, exportation, and distribution of which are subject to significant regulation by the U.S. Drug Enforcement Administration and other regulatory agencies.”

Current wording

We have never commercialized a product, and even if any of our product candidates are approved by the appropriate regulatory authorities for marketing and sale, it may nonetheless fail to achieve sufficient market acceptance by physicians, patients, third-party payors and others in the medical community. The commercial success of any of our product candidates will depend significantly on the broad adoption and use of the resulting product by these individuals and organizations for approved indications. For example, Glyph2BLSD, in development for the treatment of neuropsychiatric and headache disorders with significant unmet need, is a Glyphed oral prodrug of the non-hallucinogenic neuroplastogen, 2-bromo-LSD. There has been recent interest in psychedelics in part because of their potential to demonstrate therapeutic effects in neuropsychiatric disorders. Although Glyph2BLSD is not a psychedelic, there is a risk that it will be viewed as such by investors and the public, or could be classified as such by regulatory authorities based on its final structure. Treatments containing controlled substances or drugs that have similar effects or characteristics of controlled substances may generate public controversy or unfavorable views, which could lead to delays in, and increased expenses for, and limit or restrict the introduction and marketing of such types of therapeutic candidates. For more information on controlled substances, see subsection titled “—Certain of our product candidates may be regulated as controlled substances, the making, use, sale, importation, exportation, and distribution of which are subject to significant regulation by the U.S. Drug Enforcement Administration and other regulatory agencies.”

Previous wording

All shares of common stock sold in our IPO are be freely tradable without restriction or further registration under the Securities Act of 1933, as amended, or the Securities Act, unless held by our “affiliates” as defined in Rule 144 under the Securities Act. The resale of the remaining 38,029,523 shares, or 98% of our outstanding shares of common stock following our IPO, is currently prohibited or otherwise restricted, subject to certain limited exceptions, as a result of securities law provisions, market standoff agreements entered into by certain of our stockholders with us or lock-up agreements entered into by our stockholders with the underwriters in connection with the IPO. However, subject to applicable securities law restrictions, these shares will be able to be sold in the public market beginning on the 181 stday after the date of our IPO. Shares issued upon the exercise of stock options outstanding under our equity incentive plans or pursuant to future awards granted under those plans will become available for sale in the public market to the extent permitted by the provisions of applicable vesting schedules, market stand-off agreements and/or lock-up agreements, as well as Rules 144 and 701 under the Securities Act.

Current wording

All shares of common stock sold in our IPO are be freely tradable without restriction or further registration under the Securities Act of 1933, as amended, or the Securities Act, unless held by our “affiliates” as defined in Rule 144 under the Securities Act. The resale of the remaining 38,029,523 shares, or 98% of our outstanding shares of common stock following our IPO, is currently prohibited or otherwise restricted, subject to certain limited exceptions, as a result of securities law provisions, market standoff agreements entered into by certain of our stockholders with us or lock-up agreements entered into by our stockholders with the underwriters in connection with the IPO. However, subject to applicable securities law restrictions, these shares will be able to be sold in the public market beginning on the 18 st day after the date of our IPO. Shares issued upon the exercise of stock options outstanding under our equity incentive plans or pursuant to future awards granted under those plans will become available for sale in the public market to the extent permitted by the provisions of applicable vesting schedules, market stand-off agreements and/or lock-up agreements, as well as Rules 144 and 701 under the Securities Act.

Previous wording

If we fail to keep pace with rapidly evolving AI Technologies, especially in the medical device industry, our competitive position and business results may suffer. The introduction and use of AI Technologies, particularly generative AI, into new or existing offerings may result in new or expanded risks and liabilities, including due to enhanced governmental or regulatory scrutiny, litigation, compliance issues, ethical concerns, confidentiality or security risks, as the well as other factors that could adversely affect our reputation, as the well as our business, operating results, and financial condition. For example, AI Technologies can lead to unintended consequences, including generating content that appears correct but is factually inaccurate, misleading, or otherwise flawed, which could negatively impact our customers, harm our reputation and business, and expose us to liability.

Current wording

If we fail to keep pace with rapidly evolving AI Technologies, especially in the medical device industry, our competitive position and business results may suffer. The introduction and use of AI Technologies, particularly generative AI, into new or existing offerings may result in new or expanded risks and liabilities, including due to enhanced governmental or regulatory scrutiny, litigation, compliance issues, ethical concerns, confidentiality or security risks, as well as other factors that could adversely affect our reputation, as well as our business, operating results, and financial condition. For example, AI Technologies can lead to unintended consequences, including generating content that appears correct but is factually inaccurate, misleading, or otherwise flawed, which could negatively impact our customers, harm our reputation and business, and expose us to liability.

Previous wording

On May 1, 2026, the SEC declared effective our registration statement on Form S-1 (File No. 333-294976), as amended, or the Registration Statement, filed in connection with our IPO. Pursuant to the Registration Statement, we registered the offer and sale of 14,160,000 shares of our common stock with a maximum aggregate offering price of approximately $237.0 million. Goldman Sachs & Co. LLC, J.P. Morgan, Leerink Partners, Citigroup, and Stifel acted as representatives of the underwriters for the IPO. None of the expenses associated with the IPO were paid to directors, officers, persons owning 10% or more of any class of equity securities, or to our affiliates.

Current wording

On April 30, 2026, the SEC declared effective our registration statement on Form S-1 (File No. 333-294976), as amended, or the

Previous wording

There has been no material change in the expected use of the net proceeds from our IPO as described in our final prospectus filed with the SEC pursuant to Rule 424(b) of the Securities Act on May 1, 2026.

Current wording

There has been no material change in the expected use of the net proceeds from our IPO as described in our final prospectus filed

Previous wording

During the three months ended March 31, 2026, none of our directors or officers (as defined in Rule 16a-1(f) under the Exchange Act) adopted or terminated any “Rule 10b5-1 trading arrangement” or “non-Rule 10b5-1 trading arrangement,” as those terms are defined in Item 408 of Regulation S-K.

Current wording

During the six months ended June 30, 2026, none of our directors or officers (as defined in Rule 16a-1(f) under the Exchange Act) adopted or terminated any “Rule 10b5-1 trading arrangement” or “non-Rule 10b5-1 trading arrangement,” as those terms are defined in Item 408 of Regulation S-K.