Rapport Therapeutics, Inc.

Previous wording

A total of four Phase 1 trials in RAP-219 have been conducted to date in healthy adult volunteers: a single ascending dose (“SAD”) trial; a multiple ascending dose (“MAD”) trial; a second MAD trial (“MAD-2”), to assess dosing regimens that may accelerate time to reach therapeutic exposure; and a human positron emission tomography (“PET”) trial, which utilized a companion PET radiotracer to confirm brain target receptor occupancy and brain region specificity across a range of dosing and exposure levels. In January 2025, we announced results from our PET and MAD-2 trials of RAP-219. Data demonstrated that neuroanatomical specificity can be achieved through RAP-219’s selective targeting of TARPγ8. In Cohort 1 ofthe human PET trial, which used the dosing regimen utilized in our ongoing Phase 2a trial in patients with drug-resistant focal onset seizures, RAP-219 achieved target receptor occupancy associated with maximal seizure protection in preclinical models within five days and was generally well tolerated, which we believe further supportsthe use of such dosing regimen in the Phase 2a trial in drug-resistant focal onset seizures.

Current wording

A total of four Phase 1 trials in RAP-219 have been conducted to date in healthy adult volunteers: a single ascending dose (“SAD”) trial; a multiple ascending dose (“MAD”) trial; a second MAD trial (“MAD-2”), to assess dosing regimens that may accelerate time to reach therapeutic exposure; and a human positron emission tomography (“PET”) trial, which utilized a companion PET radiotracer to confirm brain target receptor occupancy and brain region specificity across a range of dosing and exposure levels. In January 2025, we announced results from our PET and MAD-2 trials of RAP-219. Data demonstrated that neuroanatomical specificity can be achieved through RAP-219’s selective targeting of TARPγ8. In Cohort 1 of the human PET trial, which used the dosing regimen utilized in our Phase 2a trial in patients with drug-resistant focal onset seizures, RAP-219 achieved target receptor occupancy associated with maximal seizure protection in preclinical models within five days and was generally well tolerated, which supported the use of such dosing regimen in the Phase 2a trial in drug-resistant focal onset seizures.

Previous wording

We are currently conducting a Phase 2a proof-of-concept trial in adult patients with drug-resistant focal onset seizures, for which topline results are on-track to be announced in September 2025. We believe RAP-219 also has therapeutic potential in bipolar disorder and peripheral neuropathic pain, and our Phase 2 proof-of-concept trial in bipolar mania has been initiated and is enrolling patients, with topline results expected in the first half of 2027. We were notified in the fourth quarter of 2024 by the U.S. Food and Drug Administration (“FDA”) that the Investigational New Drug (“IND”) submitted for the initiation of a Phase 2a proof-of-concept trial of RAP-219 for the treatment of diabetic peripheral neuropathic pain (“DPNP”) was placed on clinical hold. The FDA requested additional information and amendments specific to the protocol design. The clinical hold is specific to the IND for DPNP and has not impacted our ongoing Phase 2a trial in drug-resistant focal onset seizures or proof-of-concept trial in bipolar mania. We believe in our ability to advance the clinical development of RAP-219 for DPNP and will provide an update on the anticipated timing of the Phase 2a trial initiation later this year.

Current wording

We believe RAP-219 also has therapeutic potential in bipolar disorder and our Phase 2 proof-of-concept trial in bipolar mania is currently enrolling patients, with topline results expected in the first half of 2027. We also believe RAP-219 has therapeutic potential in peripheral neuropathic pain. We were notified in the fourth quarter of 2024 by the U.S. FDA that the Investigational New Drug (“IND”) submitted for the initiation of a Phase 2 proof-of-concept trial of RAP-219 for the treatment of diabetic peripheral neuropathic pain (“DPNP”) was placed on clinical hold. The FDA requested additional information and amendments specific to the protocol design. The clinical hold is specific to the IND for DPNP and has not impacted our Phase 2a trial in drug-resistant focal onset seizures or our Phase 2 proof-of-concept trial in bipolar mania. Next steps for the program are expected to be determined in the first quarter of 2026.

Previous wording

Since our inception in February 2022, we have not generated any revenue from product sales or other sources and have incurred significant operating losses and negative cash flows from our operations. We have devoted substantially all of our efforts to organizing and staffing our company, business planning, research and development activities, building our intellectual property portfolio, and providing general and administrative support for these operations. In June 2024, we completed our initial public offering (“IPO”), pursuant to which we issued and sold 9,200,000 shares of common stock (inclusive of 1,200,000 shares of common stock sold pursuant to the underwriters’ exercise of their option to purchase additional shares). In addition, we issued and sold 1,058,824 shares of common stock to certain institutional accredited investors in a concurrent private placement. The aggregate net proceeds received by us from the IPO and concurrent private placement were $157.6 million, after deducting underwriting discounts and commissions, placement agent fees as well as other offering and private placement costs of $16.8 million. To date, we have funded our operations primarily with proceeds from the issuance and sale of our common stock, convertible notes and convertible preferred stock. As of June 30, 2025, we had raised aggregate gross proceeds of $424.4 million from these financings, and had cash, cash equivalents and short-term investments of $260.4 million, excluding our restricted cash.

Current wording

In June 2024, we completed our initial public offering (“IPO”), pursuant to which we issued and sold 9,200,000 shares of common stock (inclusive of 1,200,000 shares of common stock sold pursuant to the underwriters’ exercise of their option to purchase additional shares). In addition, we issued and sold 1,058,824 shares of common stock to certain institutional accredited investors in a concurrent private placement. The aggregate net proceeds received by us from the IPO and concurrent private placement were $157.6 million, after deducting underwriting discounts and commissions, placement agent fees as well as other offering and private placement costs of $16.8 million.

Previous wording

On July 1, 2025, we filed a registration statement on Form S-3 (the “Registration Statement”) with the SEC covering the offering of up to $400.0 million of common stock, preferred stock, debt securities, warrants and/or units, which was declared effective by the SEC on July 9, 2025. Concurrent with the filing of the Registration Statement, we entered into a common stock sales agreement, dated July 1, 2025, by and between the Company and Leerink Partners LLC and Cantor Fitzgerald & Co., acting as sales agents, which established an at-the-market offering program pursuant to which we may offer and sell shares of our common stock from time to time (the “ATM Program”). In connection with the ATM Program, we also filed a prospectus with the Registration Statement for the offer and sale of up to $150.0 million of shares of common stock from time to time through the sales agents. To date, no shares have been sold through the ATM Program. As market conditions permit, we may offer and sell securities under the Registration Statement, including through the ATM Program, in order to fund our operations or provide additional liquidity.

Current wording

In July 2025, we filed a registration statement on Form S-3 (File No. 333-288444) (the “Registration Statement”) with the U.S. Securities and Exchange Commission (the “SEC”) pursuant to which we may issue up to $400.0 million in shares of our common stock, preferred stock, debt securities, warrants and/or units. As market conditions permit, we may offer and sell securities under the Registration Statement in order to fund our operations or provide additional liquidity. Concurrent with the filing of the Registration Statement, we entered into a common stock sales agreement, dated July 1, 2025, by and between the Company and Leerink Partners LLC and Cantor Fitzgerald & Co., acting as sales agents (the “Sales Agreement”), which established an at-the-market offering program pursuant to which we may offer and sell shares of our common stock from time to time (the “ATM Program”). In connection with the ATM Program, we also filed a prospectus with the Registration Statement for the offer and sale of up to $150.0 million of shares of common stock from time to time through the sales agents (the “ATM Prospectus”). Effective September 8, 2025, we terminated the ATM Prospectus, and as a result, we will not make any sales of common stock pursuant to the Sales Agreement, unless and until a new prospectus supplement or a new registration statement is filed. The Sales Agreement remains in full force and effect. As of September 8, 2025, we had not issued and sold any shares of common stock under the Sales Agreement.

Previous wording

We have incurred significant operating losses in each year since our inception. Our ability to generate product revenue sufficient to achieve profitability will depend heavily on the successful development and eventual commercialization of any product candidates we may develop. Our net losses were $26.7 million and $18.1 million for the three months ended June 30, 2025 and 2024, respectively, and $50.8 million and $40.8 million for the six months ended June 30, 2025 and 2024, respectively. As of June 30, 2025, we had an accumulated deficit of $174.5 million. We expect our expenses and operating losses will increase substantially as we:

Current wording

We have incurred significant operating losses in each year since our inception. Our ability to generate product revenue sufficient to achieve profitability will depend heavily on the successful development and eventual commercialization of any product candidates we may develop. Our net losses were $26.9 million and $17.5 million for the three months ended September 30, 2025 and 2024, respectively, and $77.7 million and $58.3 million for the nine months ended September 30, 2025 and 2024, respectively. As of

Previous wording

We believe that our existing cash and cash equivalents, and short-term investments will enable us to fund our operating expenses and capital expenditure requirements through the end of 2026. See the sections titled “—Liquidity and Capital Resources” and “Risk Factors—Risks Related to Our Limited Operating History, Financial Condition and Need for Additional Capital” included elsewhere in this Quarterly Report.

Current wording

We believe that our existing cash and cash equivalents, and short-term investments will enable us to fund our operating expenses and capital expenditure requirements into the second half of 2029. See the sections titled “—Liquidity and Capital Resources” and “Risk Factors—Risks Related to Our Limited Operating History, Financial Condition and Need for Additional Capital” included elsewhere in this Quarterly Report.

Previous wording

In August 2022, we entered into an option and license agreement with Janssen Pharmaceutical NV, as amended on April 3, 2023, April 18, 2023, May 2, 2023, October 2, 2023, and April 9, 2024 (collectively, the “Janssen License”), under which we received an exclusive option to obtain from Janssen (a) a worldwide exclusive license for the research, development, and commercialization of transmembrane TARPg 8 AMPAR products for the diagnosis, treatment, prophylaxis or palliation of any disease or condition in humans or other animals (the “Field”) and (b) an assignment of certain patents related to TARPg 8, in each case of (a)-(b), subject to certain retained rights by Janssen. Pursuant to the Janssen License, we also received a worldwide, royalty-free, non-exclusive license (exclusive under certain joint patents) for the research, development, and commercialization of certain neuronal nicotinic acetylcholine (“nACh”) products in the Field.

Current wording

In August 2022, we entered into an option and license agreement with Janssen Pharmaceutical NV, as amended on April 3, 2023, April 18, 2023, May 2, 2023, October 2, 2023, and April 9, 2024 (collectively, the “Janssen License”), under which we received an exclusive option to obtain from Janssen (a) a worldwide exclusive license for the research, development, and commercialization of transmembrane TARPg 8 AMPAR products for the diagnosis, treatment, prophylaxis or palliation of any disease or condition in humans or other animals (the “Field”) and (b) an assignment of certain patents related to TARPg 8, in each case of (a)-(b), subject to certain retained rights by Janssen. Pursuant to the Janssen License, we also received a worldwide, royalty-free, non-exclusive license

Previous wording

In November 2023, we entered into a master services agreement (the “NeuroPace Agreement”) with NeuroPace Inc. (“NeuroPace”), the manufacturer and distributor of the responsive neurostimulation (“RNS”) system. Pursuant to the NeuroPace Agreement and in accordance with statement of work agreements entered into from time to time, NeuroPace provides us with certain services with respect to data from the RNS systems used in our clinical trials. The NeuroPace Agreement also grants us a royalty-free, worldwide, exclusive, non-transferable license to all data collected by the RNS systems in our RAP-219 Phase 2a clinical trial in drug-resistant focal onset seizures and the outcomes of algorithms that are applied to such data, as well as the ability to publish the outcomes of algorithms, subject to certain conditions. The consideration we will pay to NeuroPace for such services is set out in each statement of work agreement.

Current wording

In November 2023, we entered into a master services agreement (the “NeuroPace Agreement”) with NeuroPace Inc. (“NeuroPace”), the manufacturer and distributor of the responsive neurostimulation (“RNS”) system. Pursuant to the NeuroPace Agreement and in accordance with statement of work agreements entered into from time to time, NeuroPace provides us with certain services with respect to data from the RNS systems used in our clinical trials. The NeuroPace Agreement also grants us a royalty-free, worldwide, exclusive, non-transferable license to all data collected by the RNS systems in our RAP-219 clinical trials in drug-resistant focal onset seizures and the outcomes of algorithms that are applied to such data, as well as the ability to publish the outcomes of algorithms, subject to certain conditions. The consideration we will pay to NeuroPace for such services is set out in each statement of work agreement.

Previous wording

Concurrently with the execution of the NeuroPace Agreement, the parties also entered into an initial statement of work, as amended in March 2024 (the “NeuroPace SOW”), under the NeuroPace Agreement, pursuant to which NeuroPace agreed to provide services related to our RAP-219 Phase 2a clinical trial in drug-resistant focal onset seizures, including, among other things, clinical trial readiness support, identification of potential patients satisfying the enrollment criteria and RNS system data reporting and data analysis. Pursuant to the payment schedule set out in the NeuroPace SOW, we will pay NeuroPace an aggregate of up to $3.7 million over a period of approximately two years in connection with NeuroPace’s provision of services and achievement of certain patient enrollment and deliverable milestones.

Current wording

Concurrently with the execution of the NeuroPace Agreement, the parties also entered into an initial statement of work, as amended in March 2024, and a second SOW in July 2025 (collectively, the “NeuroPace SOWs”) under the NeuroPace Agreement, pursuant to which NeuroPace agreed to provide services related to our RAP-219 Phase 2a clinical trial and planned open-label long term safety trial in RAP-219 for focal onset seizures, including, among other things, clinical trial readiness support, identification of potential patients satisfying the enrollment criteria and RNS system data reporting and data analysis. Pursuant to the payment schedule set out in the NeuroPace SOWs, the Company will pay NeuroPace an aggregate of up to $5.3 million over a period of approximately four years in connection with NeuroPace’s provision of services and achievement of certain patient enrollment and deliverable milestones.

Previous wording

For the three and six months ended June 30, 2025 and 2024, we recorded no income tax provision. As of June 30, 2025 and December 31, 2024, we recorded a full valuation allowance of our net deferred tax assets, as we believed it was more likely than not we would not be able to utilize our deferred tax assets prior to their expiration.

Current wording

For the three and nine months ended September 30, 2025 and 2024, we recorded no income tax provision. As of September 30, 2025 and December 31, 2024, we recorded a full valuation allowance of our net deferred tax assets, as we believed it was more likely than not we would not be able to utilize our deferred tax assets prior to their expiration.

Previous wording

Since our inception, we have not recorded any income tax benefits for the net losses we have incurred in each year or for our research and development tax credits, as we believe, based upon the weight of available evidence, that it is more likely than not that all of our net operating losses (“NOLs”), carryforwards and tax credits will be not realized. As of December 31, 2024, we had federal NOL carryforwards of approximately $13.7 million and state NOL carryforwards of approximately $12.0 million, respectively. Federal losses have an indefinite carryforward period, but can only offset 80% of federal taxable income in a given year. Losses for state purposes begin to expire in 2043. As of December 31, 2024, we also had federal and state tax research and development credit carryforwards of approximately $3.8 million and $1.6 million, respectively, to offset future tax liabilities, which begin to expire in 2042 and 2037, respectively. We have recorded a full valuation allowance against our net deferred tax assets at December 31, 2024. As of December 31, 2024, we had no unrecognized tax benefits. During the six months ended June 30, 2025, we utilized $0.5 million of research and development tax credits as a reduction of payroll expenses to offset our payroll tax expenses.

Current wording

Since our inception, we have not recorded any income tax benefits for the net losses we have incurred in each year or for our research and development tax credits, as we believe, based upon the weight of available evidence, that it is more likely than not that all of our net operating losses (“NOLs”), carryforwards and tax credits will be not realized. As of December 31, 2024, we had federal NOL carryforwards of approximately $13.7 million and state NOL carryforwards of approximately $12.0 million, respectively. Federal losses have an indefinite carryforward period, but can only offset 80% of federal taxable income in a given year. Losses for state purposes begin to expire in 2043. As of December 31, 2024, we also had federal and state tax research and development credit carryforwards of approximately $3.8 million and $1.6 million, respectively, to offset future tax liabilities, which begin to expire in 2042 and 2037, respectively. We have recorded a full valuation allowance against our net deferred tax assets at December 31, 2024. As of December 31, 2024, we had no unrecognized tax benefits. During the nine months ended September 30, 2025, we utilized $0.5 million of research and development tax credits as a reduction of payroll expenses to offset our payroll tax expenses.

Previous wording

On July 4, 2025, new U.S tax legislation was signed into law (known as the “One Big Beautiful Bill Act” or “OBBBA”) which makes permanent many of the tax provisions enacted in 2017 as part of the Tax Cuts and Jobs Act that were set to expire at the end of 2025. In addition, the OBBBA makes changes to certain U.S. corporate tax provisions, but many are generally not effective until 2026. We are currently evaluating the impact of the new legislation but do not expect it to have a material impact on our consolidated financial statements and related disclosures.

Current wording

On July 4, 2025, new U.S tax legislation was signed into law (known as the “One Big Beautiful Bill Act” or “OBBBA”) which makes permanent many of the tax provisions enacted in 2017 as part of the Tax Cuts and Jobs Act that were set to expire at the end of 2025. In addition, the OBBBA makes changes to certain U.S. corporate tax provisions, but many are generally not effective until 2026. The impacts of OBBBA are not expected to be material to the 2025 consolidated balance sheet or statements of operations and comprehensive loss.

Previous wording

a $8.9 million increase in RAP-219 program costs, which consisted primarily of an increase of $8.2 million in clinical trial costs primarily driven by costs for our Phase 2a trial in drug-resistant focal onset seizures, start-up costs for our Phase 2a proof-of-concept trial in DPNP, and start-up costs for our Phase 2 proof-of-concept trial in bipolar mania, and a $0.8 million increase in contract manufacturing costs related to the production of materials to support our clinical trials.

Current wording

a $3.1 million increase in RAP-219 program costs, which consisted of an increase of $3.3 million in clinical trial costs primarily driven by costs for our Phase 2a trial and open-label long term safety trial in drug-resistant focal onset seizures, costs for our Phase 2 proof-of-concept trial in bipolar mania, and a $0.3 million increase in contract manufacturing costs related to the production of materials to support our clinical trials, partially offset by a $0.5 million decrease in preclinical toxicology studies related to long-term toxicology work;

Previous wording

a $4.8 million increase in personnel-related costs due to an increase in headcount, which consisted primarily of salaries, bonuses, and other compensation-related costs of $3.6 million, and stock-based compensation of $1.2 million; and

Current wording

a $2.0 million increase in personnel-related costs due to an increase in headcount, which consisted primarily of salaries, bonuses, and other compensation-related costs of $1.5 million, and stock-based compensation of $0.5 million;

Previous wording

a $1.0 million increase in other costs, consisting primarily of research and development facilities, IT, and depreciation expense related to increased headcount and continued expansion of our Boston and San Diego sites; partially offset by

Current wording

a $0.9 million increase in other costs, consisting of research and development facilities, information technology, and depreciation expense related to increased headcount and continued expansion of our Boston and San Diego sites; and

Previous wording

a $1.6 million decrease in preclinical program costs, which consisted primarily of a $1.1 million decrease in toxicology and animal studies related to our discovery programs, a $0.2 million decrease in external chemistry efforts and other outsourced services related to our discovery programs, and a $0.2 million decrease in contract manufacturing costs related to the production of materials for use in our preclinical studies.

Current wording

a $0.8 million increase in preclinical program costs, which consisted primarily of a $0.4 million increase in toxicology and animal studies related to our discovery programs, a $0.2 million increase in external chemistry efforts, and a $0.1 million increase in contract manufacturing costs related to the production of materials for use in our preclinical studies.

Previous wording

a $1.6 million increase in workforce expense due to an increase in headcount, consisting primarily of salaries, bonuses, and other compensation-related costs of $0.2 million and stock-based compensation of $1.4 million; and

Current wording

a $1.4 million increase in workforce expense due to an increase in headcount, consisting primarily of salaries, bonuses, and other compensation-related costs of $0.4 million and stock-based compensation of $1.0 million; and

Previous wording

Other income was $2.8 million for the three months ended June 30, 2025, as compared to $2.7 million for the three months ended June 30, 2024. The increase in interest income was due to the increased cash, cash equivalent and short-term investments balances from the IPO and concurrent private placement closing in June 2024.

Current wording

Other income was $3.1 million for the three months ended September 30, 2025, as compared to $4.1 million for the three months ended September 30, 2024. The decrease in interest income was due to the decreased cash, cash equivalent and short-term investments balances for most of the three months ended September 30, 2025 due to continued spend on operations.

Previous wording

The following table summarizes our results of operations for the six months ended June 30, 2025 and 2024:

Current wording

The following table summarizes our results of operations for the nine months ended September 30, 2025 and 2024:

Previous wording

a $4.8 million increase in RAP-219 program costs, which consisted primarily of an increase of $4.1 million in clinical trial costs primarily driven by costs for our Phase 2a trial in drug-resistant focal onset seizures, start-up costs for our Phase 2a proof-of-concept trial in DPNP, and start-up costs for our Phase 2 proof-of-concept trial in bipolar mania, a $0.3 million increase in contract manufacturing costs related to the production of materials to support our clinical trials, a $0.2 million increase in preclinical toxicology studies related to long-term toxicology work, and a $0.1 million increase in consulting costs;

Current wording

a $12.0 million increase in RAP-219 program costs, which consisted primarily of an increase of $11.5 million in clinical trial costs primarily driven by costs for our Phase 2a trial and planned open-label long term safety trial in drug-resistant focal onset seizures, costs for our Phase 2 proof-of-concept trial in bipolar mania, start-up costs for our Phase 2 proof-of-concept trial in DPNP, and a $1.1 million increase in contract manufacturing costs related to the production of clinical trial supply. These increases were offset by a $0.5 million decrease in preclinical toxicology studies related to long-term toxicology work;

Previous wording

a $2.1 million increase in personnel-related costs due to an increase in headcount, which consisted primarily of salaries, bonuses, and other compensation-related costs of $1.4 million, and stock-based compensation of $0.6 million; and

Current wording

a $6.8 million increase in personnel-related costs due to an increase in headcount, which consisted primarily of salaries, bonuses, and other compensation-related costs of $5.1 million, and stock-based compensation of $1.7 million; and

Previous wording

a $1.9 million increase in other costs, consisting primarily of research and development facilities, information technology, and depreciation expenses related to increased headcount and continued expansion of our Boston and San Diego sites; partially offset by

Current wording

a $2.8 million increase in other costs, consisting primarily of research and development facilities, information technology, and depreciation expenses related to increased headcount and continued expansion of our Boston and San Diego sites; partially offset by

Previous wording

a $0.9 million decrease in preclinical program costs, which consisted primarily of a $0.6 million decrease in toxicology and animal studies related to our discovery programs, and a $0.2 million decrease in external chemistry efforts and other outsourced services related to our discovery programs.

Current wording

a $0.9 million decrease in preclinical program costs, which primarily consisted of a $0.7 million decrease in toxicology and animal studies related to our discovery programs and a $0.1 million decrease in contract manufacturing costs related to the production of materials for use in our preclinical studies.

Previous wording

a $4.2 million increase in workforce expense due to an increase in headcount, consisting primarily of salaries, bonuses, and other compensation-related costs of $0.8 million and stock-based compensation of $3.4 million; and

Current wording

a $5.6 million increase in workforce expense due to an increase in headcount, consisting primarily of salaries, bonuses, and other compensation-related costs of $1.2 million and stock-based compensation of $4.4 million; and

Previous wording

a $0.9 million increase in facility and other expenses, consisting primarily of administrative expenses due to increased business activities and expanded general and administrative support in connection with operating as a public company; partially offset by

Current wording

a $0.9 million increase in facility and other expenses, consisting of administrative expenses due to increased business activities and expanded general and administrative support in connection with operating as a public company; partially offset by

Previous wording

a $0.2 million decrease in professional and consulting fees, as higher costs were incurred in the second quarter of 2024 due to our IPO process.

Current wording

a $0.2 million decrease in professional and consulting fees, as higher costs were incurred in 2024 due to our IPO process completed in June 2024.

Previous wording

Other income (expense) was income of $5.8 million for the six months ended June 30, 2025, as compared to expense of $2.9 million for the six months ended June 30, 2024. The $7.4 million decrease in the expense from the change in fair value of preferred stock tranche right liability was due to the settlement of the Series B preferred stock tranche right liability in March 2024. The increase in interest income is due to the increased cash, cash equivalent and short-term investments balances from the Series B convertible financing in February 2024 and the IPO and concurrent private placement in June 2024.

Current wording

Other income (expense) was income of $8.9 million for the nine months ended September 30, 2025, as compared to expense of $1.2 million for the nine months ended September 30, 2024. The $7.4 million decrease in the expense from the change in fair value of preferred stock tranche right liability was due to the settlement of the Series B preferred stock tranche right liability in March 2024. The increase in interest income is due to the increased cash, cash equivalent and short-term investments balances from the IPO and concurrent private placement in June 2024 and the September 2025 Offering.

Previous wording

For each of the six months ended June 30, 2025 and 2024, we recorded an income tax provision of zero.

Current wording

For each of the nine months ended September 30, 2025 and 2024, we recorded an income tax provision of zero.

Previous wording

Since our inception in February 2022, we have not generated any revenue from any sources and have incurred significant operating losses and negative cash flows from operations. We expect to incur significant expenses and operating losses for the foreseeable future as we advance the clinical development of our product candidates and pipeline. Further, we expect to continue to incur additional costs associated with operating as a public company. Historically, we have funded our operations with proceeds from the sale of convertible notes, convertible preferred stock, and the issuance of common stock in our IPO and concurrent private placement. To date, we have received aggregate gross proceeds of $424.4 million from the issuance of convertible promissory notes and the sale of our convertible preferred stock and common stock. As of June 30, 2025, we had cash and cash equivalents and short-term investments of $260.4 million, excluding our restricted cash.

Current wording

Since our inception in February 2022, we have not generated any revenue from any sources and have incurred significant operating losses and negative cash flows from operations. We expect to incur significant expenses and operating losses for the foreseeable future as we advance the clinical development of our product candidates and pipeline. Further, we expect to continue to incur additional costs associated with operating as a public company. Historically, we have funded our operations with proceeds from the sale of convertible notes, convertible preferred stock, and the issuance of common stock in our IPO, concurrent private placement and the September 2025 Offering. To date, we have received aggregate gross proceeds of $711.9 million from the issuance of common stock, convertible promissory notes and the sale of our convertible preferred stock. As of September 30, 2025, we had cash and cash equivalents and short-term investments of $513.0 million, excluding our restricted cash.

Previous wording

During the six months ended June 30, 2025, operating activities used $45.3 million of cash, resulting primarily from our net loss of $50.8 million, non-cash accretion of investments in marketable securities of $0.5 million, and changes in operating assets and liabilities of $3.8 million, partially offset by $8.4 million of non-cash stock-based compensation expense, $0.5 million of non-cash depreciation expense, and $0.9 million of non-cash lease expense. The $3.8 million change in operating assets and liabilities is primarily driven by an increase in prepaid expenses and other current assets of $5.1 million, primarily due to advanced payments on new contracts related to our clinical trials, a $0.1 million decrease in operating lease liabilities, partially offset by increases in accounts payable of $1.2 million and accrued expenses of $0.8 million due to increased expenditures and timing of payments to vendors, and an increase in other assets of $0.5 million primarily due to the payment of the security deposit for our new corporate headquarters lease.

Current wording

During the nine months ended September 30, 2025, operating activities used $62.8 million of cash, resulting primarily from our net loss of $77.7 million, non-cash accretion of investments in marketable securities of $0.3 million, and changes in operating assets and liabilities of $0.1 million, partially offset by $13.2 million of non-cash stock-based compensation expense, $0.8 million of non-cash depreciation expense, and $1.5 million of non-cash lease expense. The $0.1 million change in operating assets and liabilities is primarily driven by an increase in prepaid expenses and other current assets of $2.6 million, primarily due to advanced payments on new contracts related to our clinical trials, a $0.1 million decrease in operating lease liabilities, and an increase in other assets of $0.9 million due to the payment of the security deposit for our new corporate headquarters lease and an up-front long-term clinical trial payment, partially offset by increases in accounts payable of $1.0 million and accrued expenses of $2.5 million due to increased expenditures and timing of payments to vendors.

Previous wording

During the six months ended June 30, 2024, operating activities used $34.0 million of cash, resulting primarily from our net loss of $40.8 million, non-cash accretion of investments in marketable securities of $1.8 million, and changes in operating assets and liabilities of $3.3 million, partially offset by $3.8 million of non-cash stock-based compensation expense and non-cash change in fair value of preferred stock tranche right liability of $7.4 million. The $3.3 million change in operating assets and liabilities is primarily driven by an increase in prepaid expenses and other current assets of $1.2 million primarily due to advanced payments on new contracts related to our clinical trials, a decrease in accounts payable of $1.0 million and accrued expenses of $0.8 million due to payments to vendors.

Current wording

During the nine months ended September 30, 2024, operating activities used $50.4 million of cash, resulting primarily from our net loss of $58.3 million, non-cash accretion of investments in marketable securities of $3.8 million, and changes in operating assets and liabilities of $3.8 million, partially offset by $7.0 million of non-cash stock-based compensation expense, non-cash change in fair value of preferred stock tranche right liability of $7.4 million, $0.6 million of non-cash depreciation expense, and $0.5 million of non-cash lease expense. The $3.8 million change in operating assets and liabilities is primarily driven by an increase in prepaid expenses and other current assets of $1.8 million, primarily due to advanced payments on new contracts related to our clinical trials, a decrease in accounts payable of $1.0 million and accrued expenses of $0.5 million due to payments to vendors, and $0.5 million decrease in operating lease liabilities.

Previous wording

During the six months ended June 30, 2024, net cash used in investing activities was $149.0 million, primarily consisting of purchases of short-term investments of $183.2 million and purchases of property and equipment of $2.0 million, partially offset by maturities of short-term investments of $36.2 million.

Current wording

During the nine months ended September 30, 2025, net cash used in investing activities was $13.1 million, primarily consisting of maturities of short-term investments of $145.0 million partially offset by purchases of short-term investments of $157.7 million and purchases of property and equipment of $0.4 million.

Previous wording

During the six months ended June 30, 2025, net cash provided by investing activities was $43.6 million, primarily consisting of maturities of short-term investments of $100.0 million partially offset by purchases of short-term investments of $56.1 million and purchases of property and equipment of $0.3 million.

Current wording

During the nine months ended September 30, 2024, net cash used in investing activities was $202.1 million, primarily consisting of purchases of short-term investments of $293.0 million and purchases of property and equipment of $2.2 million, partially offset by maturities of short-term investments of $93.1 million.

Previous wording

During the six months ended June 30, 2024, net cash provided by financing activities was $223.0 million, primarily consisting of net proceeds from our IPO and concurrent private placement of our common stock in the aggregate amount of $159.1 million, and net proceeds of $63.9 million from our additional issuance of Series B convertible preferred stock.

Current wording

During the nine months ended September 30, 2024, net cash provided by financing activities was $221.6 million, primarily consisting of net proceeds from our IPO and concurrent private placement of our common stock in the aggregate amount of $157.7 million, and net proceeds of $63.9 million from our additional issuance of Series B convertible preferred stock.

Previous wording

As of June 30, 2025, we had cash, cash equivalents and short-term investments of $260.4 million, excluding our restricted cash. As of the issuance date of the condensed consolidated financial statements for the six months ended June 30, 2025, we expect that our cash, cash equivalents and short-term investments will be sufficient to fund our operating expenses and capital expenditure requirements through at least 12 months from the issuance of the condensed consolidated financial statements. We believe that our existing cash, cash equivalents and short-term investments will enable us to fund our operating expenses and capital expenditure requirements through the end of 2026. We have based this estimate on assumptions that may prove to be wrong, and we could exhaust our available capital resources sooner than we expect. However, our forecast for the period of time through which our financial resources will be adequate to support our operations is a forward-looking statement that involves risks and uncertainties, and actual results could vary materially. Additionally, the process of conducting preclinical studies and testing potential future product candidates in clinical trials is costly, and the timing of progress and expenses in these studies and trials is uncertain. We will need to raise substantial additional capital in the future.

Current wording

As of September 30, 2025, we had cash, cash equivalents and short-term investments of $513.0 million, excluding our restricted cash. As of the issuance date of the condensed consolidated financial statements for the nine months ended September 30, 2025, we expect that our cash, cash equivalents and short-term investments will be sufficient to fund our operating expenses and capital expenditure requirements through at least 12 months from the issuance of the condensed consolidated financial statements. We believe that our existing cash, cash equivalents and short-term investments will enable us to fund our operating expenses and capital expenditure requirements into the second half of 2029. We have based this estimate on assumptions that may prove to be wrong, and we could exhaust our available capital resources sooner than we expect. However, our forecast for the period of time through which our financial resources will be adequate to support our operations is a forward-looking statement that involves risks and uncertainties, and actual results could vary materially. Additionally, the process of conducting preclinical studies and testing potential future product candidates in clinical trials is costly, and the timing of progress and expenses in these studies and trials is uncertain. We will need to raise substantial additional capital in the future.

Previous wording

As of the June 30, 2025, we had future minimum operating lease payments under non-cancelable leases of $14.2 million related to leases we have recognized on our condensed consolidated balance sheet, which included existing laboratory and office leases and the new corporate headquarters lease that commenced June 1, 2025 in Boston, Massachusetts. The future minimum operating lease payments under these non-cancelable leases are due over a weighted average remaining lease term of 5.0 years.

Current wording

As of the September 30, 2025, we had future minimum operating lease payments under non-cancelable leases of $14.0 million related to leases we have recognized on our condensed consolidated balance sheet, which included existing laboratory and office leases and the new corporate headquarters lease that commenced June 1, 2025 in Boston, Massachusetts. The future minimum operating lease payments under these non-cancelable leases are due over a weighted average remaining lease term of 4.8 years.

Previous wording

In connection with the execution of the NeuroPace Agreement, the parties also entered into an initial statement of work under the NeuroPace Agreement, pursuant to which NeuroPace agreed to provide services related to our Phase 2a proof-of-concept clinical trial of RAP-219 in patients with drug-resistant focal onset seizures, including, among other things, clinical trial readiness support, data analysis and data reporting. Pursuant to the payment schedule set out in the statement of work, we will pay NeuroPace an aggregate of up to $3.7 million over a period of approximately two years in connection with NeuroPace’s provision of services and achievement of certain patient enrollment and deliverable milestones.

Current wording

In connection with the execution of the NeuroPace Agreement, the parties also entered into an initial statement of work SOW, as amended in March 2024, and a second SOW in July 2025 (collectively, the “NeuroPace SOWs”) under the NeuroPace Agreement, pursuant to which NeuroPace agreed to provide services related to the RAP-219 Phase 2a proof-of-concept clinical trial and planned open-label long term safety trial in RAP-219 for focal onset seizures, including, among other things, clinical trial readiness support, identification of potential patients satisfying the enrollment criteria and RNS system data reporting and data analysis. Pursuant to the payment schedule set out in the NeuroPace SOWs, the Company will pay NeuroPace an aggregate of up to $5.3 million over a period of approximately four years in connection with NeuroPace’s provision of services and achievement of certain patient enrollment and deliverable milestones. The Company has incurred cumulative expenses of $3.4 million on both NeuroPace SOWs through September 30, 2025.

Previous wording

During the six months ended June 30, 2025, there were no material changes to our critical accounting policies and estimates described under Management’s Discussion and Analysis of Critical Accounting Policies and Estimates which were included in our Annual Report on Form 10-K filed with the SEC on March 11, 2025.

Current wording

During the nine months ended September 30, 2025, there were no material changes to our critical accounting policies and estimates described under Management’s Discussion and Analysis of Critical Accounting Policies and Estimates which were included in our Annual Report on Form 10-K filed with the SEC on March 11, 2025.