Acumen Pharmaceuticals, Inc.

Previous wording

We are a clinical-stage biopharmaceutical company with a limited operating history focused on pioneering a novel disease-modifying therapeutic approach to treat Alzheimer’s disease, or AD. We were incorporated in 1996 and were party to an exclusive license and research collaboration with Merck in 2003. Although we acquired the exclusive rights to sabirnetug from Merck in 2011, following Merck’s strategic decision to focus its AD development efforts on a different product candidate, we did not recommence meaningful operations until we completed our first institutional fundraising in 2018. As a result, we have a very limited operating history, which may make it difficult to evaluate the success of our business to date and to assess our future viability. Drug development is a highly uncertain undertaking and involves a substantial degree of risk. We received clearance of our Investigational New Drug application, or IND, for our sole product candidate, sabirnetug, and initiated our Phase 1 clinical trial in the second quarter of 2021. In October 2021, we announced the initial dosing of the first patient in the INTERCEPT-AD trial and in February 2023 we announced the completion of enrollment. We announced topline data from INTERCEPT-AD in July 2023. We expect to initiate our Phase 2 clinical trial, ALTITUDE-AD, in the first half of 2024. We also expect to initiate a Phase 1 clinical trial investigating a subcutaneous dosing option of sabirnetug in mid-2024. We experienced delays in clinical trial site activation and patient enrollment for INTERCEPT-AD that we believe were principally related to effects of the COVID-19 pandemic. We cannot assure you that we will not experience additional delays in site activation or enrollment. To date, we have not yet initiated a pivotal trial, obtained marketing approval for any product candidate, manufactured a commercial scale product candidate, arranged for a third party to do so on our behalf or conducted sales or marketing activities necessary for successful product candidate commercialization. Our short operating history makes any assessment of our future success and viability subject to significant uncertainty. We will likely encounter risks and difficulties frequently experienced by early-stage biopharmaceutical companies in rapidly evolving fields, and we have not yet demonstrated an ability to overcome such risks and difficulties successfully. If we do not address these risks and difficulties successfully, our business will suffer.

Current wording

We are a clinical-stage biopharmaceutical company with a limited operating history focused on pioneering a novel disease-modifying therapeutic approach to treat Alzheimer’s disease, or AD. We were incorporated in 1996 and were party to an exclusive license and research collaboration with Merck & Co., Inc., or Merck, in 2003. Although we acquired the exclusive rights to sabirnetug from Merck in 2011, following Merck’s strategic decision to focus its AD development efforts on a different product candidate, we did not recommence meaningful operations until we completed our first institutional fundraising in 2018. As a result, we have a very limited operating history, which may make it difficult to evaluate the success of our business to date and to assess our future viability. Drug development is a highly uncertain undertaking and involves a substantial degree of risk. We received clearance of our Investigational New Drug application, or IND, for our sole product candidate, sabirnetug, and initiated our Phase 1 clinical trial in the second quarter of 2021. In October 2021, we announced the initial dosing of the first patient in the INTERCEPT-AD trial and in February 2023 we announced the completion of enrollment. We announced topline data from INTERCEPT-AD in July 2023. We initiated our Phase 2 clinical trial, ALTITUDE-AD, in May 2024 and completed enrollment in March 2025. We also conducted a Phase 1 clinical trial investigating a subcutaneous dosing option of sabirnetug in mid-2024 and announced results in March 2025. We have previously experienced delays in site activation and enrollment with respect to our INTERCEPT-AD clinical trial, and cannot assure you that we will not experience additional delays in site activation or enrollment in our current or future clinical trials. To date, we have not yet initiated a pivotal trial, obtained marketing approval for any product candidate, manufactured a commercial scale product candidate, arranged for a third party to do so on our behalf or conducted sales or marketing activities necessary for successful product candidate commercialization. Our short operating history makes any assessment of our future success and viability subject to significant uncertainty. We will likely encounter risks and difficulties frequently experienced by early-stage biopharmaceutical companies in rapidly evolving fields, and we have not yet demonstrated an ability to overcome such risks and difficulties successfully. If we do not address these risks and difficulties successfully, our business will suffer.

Previous wording

We have no product candidates approved for sale, have never generated any revenue from product sales, have never been profitable and do not expect to be profitable in the foreseeable future. We have incurred net losses in each year since our inception. For the years ended December 31, 2023 and 2022, our net losses were $52.4 million and $42.9 million, respectively. As of December 31, 2023, we had an accumulated deficit of $222.8 million.

Current wording

We have no product candidates approved for sale, have never generated any revenue from product sales, have never been profitable and do not expect to be profitable in the foreseeable future. We have incurred net losses in each year since our inception. For the years ended December 31, 2024 and 2023, our net losses were $102.3 million and $52.4 million, respectively. As of December 31, 2024, we had an accumulated deficit of $325.1 million.

Previous wording

To date, we have devoted most of our financial resources to the research and development of sabirnetug, including our nonclinical development activities of sabirnetug and our INTERCEPT-AD clinical trial, and corporate overhead. We expect that it will be several years, if ever, before we have a product candidate approved and ready for commercialization. We expect to continue to incur losses for the foreseeable future, and we expect these losses to increase as we continue our development of, and seek regulatory approvals for, sabirnetug and any other product candidate we may develop in the future, prepare for and begin the commercialization of any approved product candidates and add infrastructure and personnel to support our drug development efforts and operations as a public company. We anticipate that any such losses could be significant for the next several years. These net losses and negative cash flows have had, and will continue to have, an adverse effect on our stockholders’ equity and working capital. Further, these net losses may fluctuate significantly from quarter-to-quarter or year-to-year. To become and remain profitable, we must develop and eventually commercialize sabirnetug or another drug with significant revenue.

Current wording

To date, we have devoted most of our financial resources to the research and development of sabirnetug, including our nonclinical development activities of sabirnetug and our clinical trials, and corporate overhead. We expect that it will be several years, if ever, before we have a product candidate approved and ready for commercialization. We expect to continue to incur losses for the foreseeable future, and we expect these losses to increase as we continue our development of, and seek regulatory approvals for, sabirnetug and any other product candidate we may develop in the future, prepare for and begin the commercialization of any approved product candidates and add infrastructure and personnel to support our drug development efforts and operations as a public company. We anticipate that any such losses could be significant for the next several years. These net losses and negative cash flows have had, and will continue to have, an adverse effect on our stockholders’ equity and working capital. Further, these net losses may fluctuate significantly from quarter-to-quarter or year-to-year. To become and remain profitable, we must develop and eventually commercialize sabirnetug or another drug with significant revenue.

Previous wording

To date, we have used substantial amounts of cash to fund our operations, and we expect our expenses to increase substantially in the foreseeable future in connection with our ongoing activities, particularly as we continue the research and development, conduct clinical trials of, and seek marketing approval for, sabirnetug. Developing sabirnetug and conducting clinical trials for the treatment of AD and any other product candidates or indications that we may pursue in the future will require substantial amounts of capital. In addition, if we obtain marketing approval for sabirnetug or any future product candidates, we expect to incur significant commercialization expenses related to the commercialization of the product, whether we are commercializing alone or with a collaborator. Further, we expect to incur additional significant expenses associated with operating as a public company.

Current wording

To date, we have used substantial amounts of cash to fund our operations, and we expect our expenses to increase substantially in the foreseeable future in connection with our ongoing activities, particularly as we continue the research and development, conduct clinical trials of, and seek marketing approval for, sabirnetug. Developing sabirnetug and conducting clinical trials for the treatment of AD and any other product candidates or indications that we may pursue in the future will require substantial amounts of capital. In addition, if we obtain marketing approval for sabirnetug or any future product candidates, we expect to incur significant commercialization expenses related to the commercialization of the product, whether we are commercializing alone or with a collaborator. Further, we expect to incur significant expenses associated with operating as a public company.

Previous wording

Accordingly, we will need to obtain substantial additional funding in connection with our continuing operations. As of December 31, 2023, we had $66.9 million in cash and cash equivalents and $239.2 million in marketable securities; included in this amount is the first tranche of$30.0 million that we received under our Loan and Security Agreement with K2 HealthVentures LLC, or the Loan Agreement, which was received on November 10, 2023. Based on our current operating plan, we believe that our existing cash and cash equivalents and marketable securities will be sufficient to enable us to fund our operating expenses and capital expenditure requirements into the first half of 2027. In addition, changing circumstances may cause us to increase our spending significantly faster than we currently anticipate, and we may need to spend more money than currently expected because of circumstances beyond our control. We may need to raise additional funds sooner than anticipated if we choose to expand more rapidly than we presently anticipate.

Current wording

Accordingly, we will need to obtain substantial additional funding in connection with our continuing operations. As of December 31, 2024, we had $35.6 million in cash and cash equivalents and $195.9 million in marketable securities; included in this amount is the first tranche of $30.0 million that we received under our loan and security agreement with K2 HealthVentures LLC, or the Loan Agreement, which was received on November 10, 2023. Based on our current operating plan, we believe that our existing cash and cash equivalents and marketable securities will be sufficient to enable us to fund our operating expenses and capital expenditure requirements into the first half of 2027. In addition, changing circumstances may cause us to increase our spending significantly faster than we currently anticipate, and we may need to spend more money than currently expected because of circumstances beyond our control. We may need to raise additional funds sooner than anticipated if we choose to expand more rapidly than we presently anticipate.

Previous wording

•the requirements of the FDA and EMA, and comparable foreign regulatory authorities, for clinical trials and nonclinical studies and other work, for review and approval of sabirnetug for AD;

Current wording

•the requirements of the U.S. Food and Drug Administration, or FDA, and the European Medicines Agency, or EMA, and comparable foreign regulatory authorities, for clinical trials and nonclinical studies and other work, for review and approval of sabirnetug for AD;

Previous wording

Additional funding may not be available to us on acceptable terms or at all. Any such funding may result in dilution to stockholders, imposition of debt covenants and repayment obligations or other restrictions that may affect our business. We also could be required to seek funds through arrangements with collaborative partners or otherwise that may require us to relinquish rights to some of our technologies or product candidates or otherwise agree to terms unfavorable to us. Any funds we raise may not be sufficient to enable us to continue to implement our long-term business strategy. Further, our ability to raise additional capital may be adversely impacted by potential worsening global economic conditions and the recent disruptions to and volatility in the credit and financial markets in the United States and worldwide. Additionally, escalation in interest rates, in conjunction with banking failures, may lead to financial institutions being more prudent with capital deployment and tightening lending. If we are unable to raise sufficient additional capital on a timely basis, we could be forced to curtail our planned operations and the pursuit of our business strategy, which would have a material adverse effect on the value of our common stock.

Current wording

Additional funding may not be available to us on acceptable terms or at all. Any such funding may result in dilution to stockholders, imposition of debt covenants and repayment obligations or other restrictions that may affect our business. We also could be required to seek funds through arrangements with collaborative partners or otherwise that may require us to relinquish rights to some of our technologies or product candidates or otherwise agree to terms unfavorable to us. Any funds we raise may not be sufficient to enable us to continue to implement our long-term business strategy. Further, our ability to raise additional capital may be adversely impacted by potential worsening global economic conditions. Additionally, escalation in interest rates may lead to financial institutions being more prudent with capital deployment and tightening lending. If we are unable to raise sufficient additional capital on a timely basis, we could be forced to curtail our planned operations and the pursuit of our business strategy, which would have a material adverse effect on the value of our common stock.

Previous wording

Our obligations under the Loan Agreement are secured by a security interest in substantially all of our assets, excluding the Company’s intellectual property. The Loan Agreement includes customary affirmative and negative covenants, as well as standard events of default, including an event of default based on the occurrence of a material adverse event. The negative covenants include, among others, restrictions on us transferring collateral, incurring additional indebtedness, engaging in mergers or acquisitions, paying cash dividends or making other distributions, making investments, creating liens, selling assets and making any payment on subordinated debt, in each case subject to certain exceptions. These restrictive covenants could limit our flexibility in operating our business and our ability to pursue business opportunities that we or our stockholders may consider beneficial. In addition, K2HV could declare a default upon the occurrence of any event that it interprets could have material adverse effect, subject to the limitations specified in the Loan Agreement. Upon the occurrence and continuance of an event of default, K2HV may declare all outstanding obligations immediately due and payable and take such other actions as set forth in the Loan Agreement. Any declaration of an event of default could significantly harm our business and prospects and could cause the price of our common stock to decline. If we are liquidated, the rights of our lenders to repayment would be senior to the rights of the holders of our common stock to receive any proceeds from the liquidation. We may not have enough available cash or be able to raise additional funds through equity or debt financings to repay these outstanding obligations at the time any event of default occurs. Further, if we raise any additional capital through debt financing, the terms of such additional debt could further restrict our operating and financial flexibility.

Current wording

Our obligations under the Loan Agreement are secured by a security interest in substantially all of our assets, excluding the Company’s intellectual property. The Loan Agreement includes customary affirmative and negative covenants, as well as standard events of default, including an event of default based on the occurrence of a material adverse event. The negative covenants include, among others, restrictions on us transferring collateral, incurring additional indebtedness, engaging in mergers or acquisitions, paying cash dividends or making other distributions, making investments, creating liens, selling assets and making any payment on subordinated debt, in each case subject to certain exceptions. These restrictive covenants could limit our flexibility in operating our business and our ability to pursue business opportunities that we or our stockholders may consider beneficial. In addition, K2HV could declare a default upon the occurrence of any event that it interprets could have a material adverse effect, subject to the limitations specified in the Loan Agreement. Upon the occurrence and continuance of an event of default, K2HV may declare all outstanding obligations immediately due and payable and take such other actions as set forth in the Loan Agreement. Any declaration of an event of default could significantly harm our business and prospects and could cause the price of our common stock to decline. If we are liquidated, the rights of our lenders to repayment would be senior to the rights of the holders of our common stock to receive any proceeds from the liquidation. We may not have enough available cash or be able to raise additional funds through equity or debt financings to repay these outstanding obligations at the time any event of default occurs. Further, if we raise any additional capital through debt financing, the terms of such additional debt could further restrict our operating and financial flexibility.

Previous wording

We are exposed to market risk from changes in interest rates. Under the Loan Agreement with K2HV, our term loan facility bears a variable interest rate equal to the greater of (i) 9.65% and (ii) the sum of (A) the prime rate last quoted in The Wall Street Journal and (B) 1.15%. The Federal Reserve has recently raised, and may in the future further raise, interest rates to combat the effects of recent high inflation. An increase in interest rates by the Federal Reserve could cause the prime rate to increase, which could increase our debt service obligations. Significant increases in such obligations could have a negative impact on our financial position or operating results, including cash available for servicing our indebtedness, or result in increased borrowing costs in the future.

Current wording

We are exposed to market risk from changes in interest rates. Under the Loan Agreement with K2HV, our term loan facility bears a variable interest rate equal to the greater of (i) 9.65% and (ii) the sum of (A) the prime rate last quoted in The Wall Street Journal and (B) 1.15%. An increase in interest rates by the Federal Reserve could cause the prime rate to increase, which could increase our debt service obligations. Significant increases in such obligations could have a negative impact on our financial position or operating results, including cash available for servicing our indebtedness, or result in increased borrowing costs in the future.

Previous wording

We are early in our development efforts. To date, we have invested substantially all of our efforts and financial resources in the research and development and INTERCEPT-AD Phase 1 clinical trial of sabirnetug, which is currently our only product candidate. Before seeking marketing approval from regulatory authorities for the sale of sabirnetug, we must conduct extensive clinical trials to demonstrate the safety and efficacy of the drug in humans. We are not permitted to market or promote any product candidate before we receive regulatory approval from the FDA, or comparable foreign regulatory authorities, and we may never receive such regulatory approval. We cannot be certain that sabirnetug will be successful in clinical trials. Further, sabirnetug may not receive regulatory approval even if it is successful in clinical trials. If we do not receive regulatory approvals for sabirnetug, we may not be able to continue our operations. Our prospects, including our ability to finance our operations and generate revenue, will depend entirely on the successful development, regulatory approval and commercialization of sabirnetug by us or by one or more of our partners. The clinical and commercial success of sabirnetug will depend on a number of factors, including the following:

Current wording

We are early in our development efforts. To date, we have invested substantially all of our efforts and financial resources in the research and development and clinical trials of sabirnetug, which is currently our only product candidate. Before seeking marketing approval from regulatory authorities for the sale of sabirnetug, we must conduct extensive clinical trials to demonstrate the safety and efficacy of the drug in humans. We are not permitted to market or promote any product candidate before we receive regulatory approval from the FDA, or comparable foreign regulatory authorities, and we may never receive such regulatory approval. We cannot be certain that sabirnetug will be successful in clinical trials. Further, sabirnetug may not receive regulatory approval even if it is successful in clinical trials. If we do not receive regulatory approvals for sabirnetug, we may not be able to continue our operations. Our prospects, including our ability to finance our operations and generate revenue, will depend entirely on the successful development, regulatory approval and commercialization of sabirnetug by us or by one or more of our partners. The clinical and commercial success of sabirnetug will depend on a number of factors, including the following:

Previous wording

•successful patient enrollment in INTERCEPT-AD, ALTITUDE-AD and other clinical trials of sabirnetug;

Current wording

•successful patient enrollment in ALTITUDE-AD and other clinical trials of sabirnetug;

Previous wording

•the results from INTERCEPT-AD, ALTITUDE-AD and future clinical trials of sabirnetug;

Current wording

•the results from ALTITUDE-AD and future clinical trials of sabirnetug;

Previous wording

•the ability of third-party manufacturers to manufacture supplies of sabirnetug and to develop, validate and maintain a commercial-scale manufacturing process that is compliant with current good manufacturing practices, or cGMP;

Current wording

•the ability of third-party manufacturers to manufacture supplies of sabirnetug and to develop, validate and maintain a commercial-scale manufacturing process that is compliant with current good manufacturing practices, or cGMPs;

Previous wording

•our ability to demonstrate sabirnetug’s safety and efficacy to the satisfaction of the FDA and foreign regulatory authorities in order to receive necessary marketing approvals for sabirnetug;

Current wording

•our ability to demonstrate sabirnetug’s safety and efficacy to the satisfaction of the FDA, EMA and any foreign regulatory authorities in order to receive necessary marketing approvals for sabirnetug;

Previous wording

•whether we are required by the FDA to conduct additional clinical trials prior to the approval to market sabirnetug and whether the FDA may disagree with the number, design, size, conduct, implementation or other aspects of our clinical trials;

Current wording

•whether we are required by the FDA, EMA or other regulatory authorities to conduct additional clinical trials prior to the approval to market sabirnetug and whether the FDA, EMA or other regulatory authorities may disagree with the number, design, size, conduct, implementation or other aspects of our clinical trials;

Previous wording

•whether the FDA may require implementation of a Risk Evaluation and Mitigation Strategy, or REMS, as a condition of approval or post-approval;

Current wording

•whether the FDA, EMA or other regulatory authorities may require implementation of a Risk Evaluation and Mitigation Strategy, or REMS, as a condition of approval or post-approval;

Previous wording

•our ability to successfully commercialize sabirnetug, if approved for marketing and sale by the FDA or foreign regulatory authorities, whether alone or in collaboration with others;

Current wording

•our ability to successfully commercialize sabirnetug, if approved for marketing and sale by the FDA, EMA or foreign regulatory authorities, whether alone or in collaboration with others;

Previous wording

•achieving and maintaining compliance with all regulatory requirements applicable to sabirnetug, including any required post-marketing approval commitments;

Current wording

•our ability to achieve and maintain compliance with all regulatory requirements applicable to sabirnetug, including any required post-marketing approval commitments;

Previous wording

The FDA granted Fast Track designation for sabirnetug for the treatment of early AD in October 2022, and we may in the future seek Fast Track designation for any other product candidates we may develop. If a drug or biologic is intended for the treatment of a serious or life-threatening condition and the product demonstrates the potential to address unmet medical needs for this condition, the sponsor may apply for FDA Fast Track designation for a particular indication. There is no assurance that the FDA will grant this status to any of our other product candidates. If granted, Fast Track designation makes a product eligible for more frequent interactions with FDA to discuss the development plan and clinical trial design, as well as rolling review of the application, which means that the company can submit completed sections of its marketing application for review prior to completion of the entire submission. Marketing applications of product candidates with Fast Track designation may qualify for priority review under the policies and procedures offered by the FDA, but the Fast Track designation does not assure any such qualification or ultimate marketing approval by the FDA. The FDA has broad discretion whether or not to grant Fast Track designation, so even if we believe a particular product candidate is eligible for this designation, there can be no assurance that the FDA would decide to grant it. Even if we do receive Fast Track designation, we may not experience a faster development process, review or approval compared to conventional FDA procedures, and receiving a Fast Track designation does not provide any assurance of ultimate FDA approval. In addition, the FDA may withdraw Fast Track designation at any time if it believes that the designation is no longer supported by data from our clinical development program.

Current wording

The FDA granted Fast Track designation for sabirnetug for the treatment of early AD in October 2022, and we may in the future seek Fast Track designation for any other product candidates we may develop. If a drug or biologic is intended for the treatment of a serious or life-threatening condition and the product demonstrates the potential to address unmet medical needs for this condition, the sponsor may apply for FDA Fast Track designation for a particular indication. There is no assurance that the FDA will grant this status to any of our other product candidates. If granted, Fast Track designation makes a product eligible for more frequent interactions with FDA to discuss the development plan and clinical trial design, as well as rolling review of the application, which means that the company can submit completed sections of its marketing application for review prior to completion of the entire submission. Marketing applications of product candidates with Fast Track designation may qualify for priority review under the policies and procedures offered by the FDA, but the Fast Track designation does not assure any such qualification or ultimate marketing approval by the FDA. The FDA has broad discretion to decide whether to grant Fast Track designation, so even if we believe a particular product candidate is eligible for this designation, there can be no assurance that the FDA would decide to grant it. Even if we do receive Fast Track designation, we may not experience a faster development, review or approval process compared to conventional FDA procedures. In addition, the FDA may withdraw Fast Track designation at any time if it believes that the designation is no longer supported by data from our clinical development program.

Previous wording

Our future success is highly dependent on the successful development of sabirnetug for treating AD. The development and, if approved, commercialization of sabirnetug subjects us to a number of challenges, including ensuring that we select an effective dose of sabirnetug, executing appropriate clinical trials to test for safety and efficacy and obtaining regulatory approval from the FDA and other regulatory authorities. We cannot be sure that sabirnetug, or any other product candidate we develop, will ultimately prove to be safe and effective, scalable or profitable. Moreover, public perception of drug safety issues, including adoption of new therapeutics or novel approaches to treatment, may adversely influence the willingness of subjects to participate in clinical trials, or if approved, of physicians to prescribe novel treatments.

Current wording

Our future success is highly dependent on the successful development of sabirnetug for treating AD. The development and, if approved, commercialization of sabirnetug subjects us to a number of challenges, including ensuring that we select an effective dose of sabirnetug, executing appropriate clinical trials to test for safety and efficacy and obtaining regulatory approval from the FDA and other regulatory authorities. We cannot be sure that sabirnetug, or any other product candidate we develop, will ultimately prove to be safe and effective, scalable or profitable. Moreover, public perception of drug safety issues, including adoption of new therapeutics or novel approaches to treatment, may adversely influence the willingness of subjects to participate in clinical trials, or if approved, the willingness of physicians to prescribe novel treatments.

Previous wording

There is no current scientific or general consensus on the causation of AD or method of action to treat AD. We have discovered and are developing sabirnetug, a humanized monoclonal antibody that selectively targets amyloid-beta oligomers, or AßOs, to treat AD. Our approach is based on research on AßOs, globular assemblies of the amyloid-beta, or Aß, peptide that are distinct from other forms of amyloid. AßOs have gained scientific acceptance as important toxins involved in the initiation and propagation of AD pathology. Based on the results of our nonclinical studies to date and our INTERCEPT-AD Phase 1 clinical trial, we believe sabirnetug represents a differentiated approach from current and prior anti-Aß/plaque immunotherapies because it is highly selective for soluble AßOs. We believe that sabirnetug is the most advanced immunotherapy candidate in development that was designed to selectively target AßOs. However, we may ultimately discover that sabirnetug does not possess properties required for therapeutic effectiveness. We may spend substantial funds attempting to develop sabirnetug or other product candidates and never succeed in doing so.

Current wording

There is no current scientific or general consensus on the causation of AD or method of action to treat AD. We have discovered and are developing sabirnetug, a humanized monoclonal antibody that selectively targets amyloid-beta oligomers, or AßOs, to treat AD. Our approach is based on research on AßOs, globular assemblies of the amyloid-beta, or Aß, peptide that are distinct from other forms of amyloid. AßOs have gained increasing scientific acceptance as a primary toxin involved in the initiation and propagation of AD pathology. Based on the results of our nonclinical studies to date and our INTERCEPT-AD Phase 1 clinical trial, we believe sabirnetug represents a differentiated approach from current and prior anti-Aß/plaque immunotherapies because of its selectivity for soluble AßOs. We believe that sabirnetug is the most advanced immunotherapy candidate in development that was designed to selectively target AßOs. However, we may ultimately discover that sabirnetug does not possess properties required for therapeutic effectiveness. We may spend substantial funds attempting to develop sabirnetug or other product candidates and never succeed in doing so.

Previous wording

Clinical failure can occur at any stage of clinical development and we have never submitted a biologics license application, or BLA, or other marketing authorization application.

Current wording

Clinical failure can occur at any stage of clinical development, and we have never submitted a biologics license application, or BLA, or other marketing authorization application, or MAA.

Previous wording

We are early in our development efforts for sabirnetug and will need to successfully complete our ongoing and planned clinical trials, including pivotal clinical trials, in order to obtain FDA approval to market sabirnetug or any other product candidate we seek to develop. Carrying out clinical trials and the submission of a successful BLA is a complicated process. Although members of the Acumen team have significant experience in clinical development of drugs through regulatory approval, as an organization, Acumen recently conducted its first clinical trial, had no previous experience in conducting any clinical trials, has limited experience in preparing regulatory submissions and has not previously submitted a BLA for any product candidate.

Current wording

We are early in our development efforts for sabirnetug and will need to successfully complete our ongoing and planned clinical trials, including pivotal clinical trials, in order to obtain FDA approval to market sabirnetug or any other product candidate we seek to develop. Carrying out clinical trials and the submission of a successful BLA is a complicated process. Although members of the Acumen team have significant experience in clinical development of drugs through regulatory approval, as an organization, Acumen only recently completed its first clinical trial, has no previous experience in conducting any other clinical trials, has limited experience in preparing regulatory submissions and has not previously submitted a BLA for any product candidate.

Previous wording

In addition, we have had limited interactions with the FDA and have received important feedback on the design of ALTITUDE-AD; however, we cannot be certain how many clinical trials of sabirnetug will be required or how such trials will be designed. Consequently, we may be unable to successfully and efficiently execute and complete necessary clinical trials in a way that leads to BLA submission and approval of sabirnetug or any other product candidate. We may require more time and incur greater costs than our competitors and we may not succeed in obtaining regulatory approvals of product candidates that we develop. Failure to commence or complete, or delays in, our planned clinical trials, could prevent us from or delay us in commercializing sabirnetug or any future product candidates we may develop, and failure to successfully complete any of these activities in a timely manner could have a material adverse impact on our business and financial performance.

Current wording

In addition, we have had limited interactions with the FDA and have received important feedback on the design of ALTITUDE-AD; similarly, based on regulatory feedback from the EMA and to enhance the probability that the EMA will consider our Phase 2 clinical trial a registration-eligible clinical trial for sabirnetug, we amended the ALTITUDE-AD protocol in 2024 to change from a Phase 2/3 clinical trial to a Phase 2 standalone clinical trial. However, we cannot be certain how many clinical trials of sabirnetug will be required or how such trials will be designed. Consequently, we may be unable to successfully and efficiently execute and complete necessary clinical trials in a way that leads to submission of a BLA or request for marketing authorization and approval of sabirnetug or any other product candidate. We may require more time and incur greater costs than our competitors and we may not succeed in obtaining regulatory approvals of product candidates that we develop. Failure to commence or complete, or delays in, our planned clinical trials, could prevent us from or delay us in commercializing sabirnetug or any future product candidates we may develop, and failure to successfully complete any of these activities in a timely manner could have a material adverse impact on our business and financial performance.

Previous wording

•regulatory authorities in jurisdictions in which we seek to conduct clinical trials may differ from each other on our trial design, and it may be difficult or impossible to satisfy all such authorities with one approach;

Current wording

•regulatory authorities in jurisdictions in which we seek to conduct clinical trials may have differing views on our trial design, and it may be difficult or impossible to satisfy all such authorities with one approach;

Previous wording

•our third-party contractors, including clinical investigators, contract manufacturers and vendors may fail to comply with applicable regulatory requirements, lose their licenses or permits, or otherwise fail, or lose the ability to, meet their contractual obligations to us in a timely manner, or at all;

Current wording

•our third-party contractors, including clinical investigators, contract manufacturers and vendors may fail to comply with applicable regulatory requirements, lose their licenses or permits, or otherwise fail to, or lose the ability to, meet their contractual obligations to us in a timely manner, or at all;

Previous wording

•clinical trial sites may deviate from clinical trial protocol or drop out of a clinical trial; and

Current wording

•clinical trial sites may deviate from clinical trial protocol or drop out of a clinical trial;

Previous wording

As is the case with pharmaceuticals generally, it is possible that there may be side effects and adverse events associated with the use of sabirnetug or any future product candidates we may develop. Results of ALTITUDE-AD, or future clinical trials, could reveal a high and unacceptable severity and prevalence of side effects or unexpected characteristics as the clinical trials progress to greater exposures and a larger number of patients. Undesirable side effects caused by, or unexpected or unacceptable characteristics associated with, sabirnetug or any future product candidates we may develop, could result in the delay, suspension or termination of clinical trials by us, the FDA or other regulatory authorities, or IRBs for a number of reasons. We may also elect to limit their development to more narrow uses or subpopulations in which the undesirable side effects or other characteristics are less prevalent, less severe or more acceptable from a risk-benefit perspective, which may limit the commercial expectations for such product candidate, if approved. If we elect or are required to further delay, suspend or terminate any clinical trial of any product candidates we may develop, the commercial prospects of such product candidates will be harmed and our ability to generate drug revenues from any such product candidates will be delayed or eliminated.

Current wording

As is the case with pharmaceuticals generally, it is possible that there may be side effects and adverse events associated with the use of sabirnetug or any future product candidates we may develop. For example, with respect to our INTERCEPT-AD clinical trial, the most common treatment-emergent adverse events from all dose groups combined were ARIA-E (10.4%), ARIA-H (hemorrhage) (8.3%), COVID-19 (6.3%), and hypersensitivity (6.3%). The overall rate of ARIA-E was 10.4%, which included one case of symptomatic ARIA-E (2.1%). Results of ALTITUDE-AD, or future clinical trials, could reveal a high and unacceptable severity and prevalence of side effects or unexpected characteristics as the clinical trials progress to greater exposures and a larger number of patients. Undesirable side effects caused by, or unexpected or unacceptable characteristics associated with, sabirnetug or any future product candidates we may develop, could result in the delay, suspension or termination of clinical trials by us, the FDA or other comparable regulatory authorities, or IRBs for a number of reasons. We may also elect to limit their development to more narrow uses or subpopulations in which the undesirable side effects or other characteristics are less prevalent, less severe or more acceptable from a risk-benefit perspective, which may limit the commercial expectations for such product candidate, if approved. If we elect or are required to further delay, suspend or terminate any clinical trial of any product candidates we may develop, the commercial prospects of such product candidates will be harmed and our ability to generate drug revenues from any such product candidates will be delayed or eliminated.

Previous wording

It is possible that, as we test sabirnetug in INTERCEPT-AD, ALTITUDE-AD or future trials, or as the use of sabirnetug becomes more widespread if it receives regulatory approval, we may identify additional adverse events that were not identified or not considered significant in our earlier trials. If such side effects become later known in development or upon approval, if any, such findings may harm our business, financial condition, results of operations and prospects significantly. If we or others later identify undesirable side effects, a number of potentially significant negative consequences could result, including:

Current wording

It is possible that as we test sabirnetug in ALTITUDE-AD or future clinical trials, or as the use of sabirnetug becomes more widespread if it receives regulatory approval, we may identify additional adverse events that were not identified or not considered significant in our earlier trials. If such side effects, if any, become later known in development or upon approval, such findings may harm our business, financial condition, results of operations and prospects significantly. If we or others later identify undesirable side effects, a number of potentially significant negative consequences could result, including:

Previous wording

•regulatory authorities may require additional warnings or statements in the labeling, such as a boxed warning or a contraindication or issue safety alerts, press releases or other communications containing warnings or other safety information about the product candidate, for example, field alerts to physicians and pharmacies;

Current wording

•regulatory authorities may require additional warnings or statements in the labeling, such as a boxed warning or a contraindication, or issue safety alerts, press releases or other communications containing warnings or other safety information about the product candidate, such as field alerts to physicians and pharmacies;

Previous wording

Trials may be subject to delays as a result of patient enrollment taking longer than anticipated or patient withdrawal. We may not be able to initiate or continue clinical trials for our product candidates if we are unable to locate and enroll a sufficient number of eligible patients to participate in these trials as required by the FDA or foreign regulatory authorities. We cannot predict how successful we will be at enrolling subjects in future clinical trials. Throughout 2022, we experienced delays in clinical site initiation and patient enrollment that we believe were principally related to the effects of the COVID-19 pandemic. Although those enrollment delays were resolved, including through the addition of new clinical trial sites, we may experience other enrollment delays in the future. Subject enrollment is affected by other factors including:

Current wording

Trials may be subject to delays as a result of patient enrollment taking longer than anticipated or patient withdrawal. We may not be able to initiate or continue clinical trials for our product candidates if we are unable to locate and enroll a sufficient number of eligible patients to participate in these trials as required by the FDA or comparable foreign regulatory authorities. Throughout 2022, we experienced delays in clinical site initiation and patient enrollment that we believe were principally related to the effects of the COVID-19 pandemic. Although those enrollment delays were resolved, including through the addition of new clinical trial sites, we may experience other enrollment delays in the future. We cannot predict how successful we will be at enrolling subjects in future clinical trials. Subject enrollment is affected by other factors including:

Previous wording

Our inability to enroll a sufficient number of patients for clinical trials would result in significant delays and could require us to abandon one or more clinical trials altogether. The enrollment delays we experienced in our INTERCEPT-AD clinical trial resulted in increased development costs for the trial, including costs related to initiating additional trial sites, and any future enrollment delays we may experience in clinical trials of sabirnetug or any other product candidates we may develop may result in increased development costs for our product candidates, which would harm our business, financial condition and results of operations.

Current wording

Our inability to enroll a sufficient number of patients for clinical trials would result in significant delays and could require us to abandon one or more clinical trials altogether. The enrollment delays we experienced in our INTERCEPT-AD clinical trial resulted in increased development costs for the trial, including costs related to initiating additional trial sites, and any enrollment delays we may experience in future clinical trials of sabirnetug or any other product candidates we may develop may result in increased development costs for our product candidates, which would harm our business, financial condition and results of operations.

Previous wording

The development of a product candidate and its approval and commercialization, including its design, testing, manufacture, safety, efficacy, recordkeeping, labeling, storage, approval, advertising, promotion, sale, distribution, import and export are subject to extensive regulation by the FDA, the EMA and regulatory authorities in other countries, with regulations differing from country to country. We are not permitted to market our product candidates in the United States, Europe or other countries until we receive approval of a BLA from the FDA or MAA from the EMA, respectively. We have not submitted any marketing applications for sabirnetug.

Current wording

The development of a product candidate and its approval and commercialization, including its design, testing, manufacture, safety, efficacy, recordkeeping, labeling, storage, approval, advertising, promotion, sale, distribution, import and export are subject to extensive regulation by the FDA, the EMA and comparable regulatory authorities in other countries, with regulations differing from country to country. We are not permitted to market our product candidates in the United States, Europe or other countries until we receive approval of a BLA from the FDA or MAA from the EMA, respectively. We have not submitted any marketing applications for sabirnetug.

Previous wording

We have completed the INTERCEPT-AD Phase 1 clinical trial in patients with AD and expect to initiate a Phase 2 clinical trial in the first half of 2024. Before we submit a BLA to the FDA or an MAA to the EMA for sabirnetug for the treatment of patients with AD, we will be required to successfully complete at least one pivotal clinical trial. The FDA and the EMA generally expect two pivotal clinical trials to support approval, although a single pivotal trial may be allowed in certain circumstances. In addition, we must scale up manufacturing and complete other standard nonclinical and clinical studies. We cannot predict whether our current or future trials will be successful or whether regulators will agree with our plans or conclusions regarding the nonclinical studies and the clinical trials we conduct.

Current wording

Before we submit a BLA to the FDA or an MAA to the EMA for sabirnetug for the treatment of patients with AD, we will be required to successfully complete at least one pivotal clinical trial. The FDA and the EMA generally expect two pivotal clinical trials to support approval, although a single pivotal trial may be allowed in certain circumstances. In addition, we must scale up manufacturing and complete other standard nonclinical and clinical studies. We cannot predict whether our current or future trials will be successful or whether regulators will agree with our plans or conclusions regarding the nonclinical studies and the clinical trials we conduct.

Previous wording

We may in the future conduct clinical trials for our product candidates outside the United States, and the FDA, EMA and other foreign regulatory authorities may not accept data from such trials.

Current wording

We may in the future conduct clinical trials for our product candidates outside the United States, and the FDA, EMA and other comparable foreign regulatory authorities may not accept data from such trials.

Previous wording

We may in the future choose to conduct one or more of our clinical trials outside the United States, including in Europe. The acceptance of study data from clinical trials conducted outside the United States or another jurisdiction by the FDA, EMA or applicable foreign regulatory authorities may be subject to certain conditions or may not be accepted at all. In cases where data from foreign clinical trials are intended to serve as the basis for marketing approval in the United States, the FDA will generally not approve the application on the basis of foreign data alone unless (i) the data are applicable to the United States population and United States medical practice; and (ii) the trials were performed by clinical investigators of recognized competence and pursuant to current good clinical practice, or cGCP, regulations. Additionally, the FDA’s clinical trial requirements, including sufficient size of patient populations and statistical powering, must be met. Many foreign regulatory bodies have similar approval requirements. In addition, such foreign trials would be subject to the applicable local laws of the foreign jurisdictions where the trials are conducted. There can be no assurance that the FDA, EMA or any other foreign regulatory authority will accept data from trials conducted outside of the United States or the applicable jurisdiction. If the FDA, EMA or any applicable foreign regulatory authority does not accept such data, it would result in the need for additional trials, which would be costly and time-consuming and delay aspects of our business plan, and which may result in our product candidates not receiving approval or clearance for commercialization in the applicable jurisdiction.

Current wording

We may in the future choose to conduct one or more of our clinical trials outside the United States, including in Europe. The acceptance of study data from clinical trials conducted outside the United States or another jurisdiction by the FDA, EMA or applicable foreign regulatory authorities may be subject to certain conditions or may not be accepted at all. In cases where data from foreign clinical trials are intended to serve as the basis for marketing approval in the United States, the FDA will generally not approve the application on the basis of foreign data alone unless (i) the data are applicable to the United States population and United States medical practice; and (ii) the trials were performed by clinical investigators of recognized competence and pursuant to current good clinical practice, or cGCP, regulations. Additionally, the FDA’s clinical trial requirements, including sufficient size of patient populations and statistical powering, must be met. Many foreign regulatory bodies have similar approval requirements. In addition, such foreign trials would be subject to the applicable local laws of the foreign jurisdictions where the trials are conducted. There can be no assurance that the FDA, EMA or any other comparable foreign regulatory authority will accept data from trials conducted outside of the United States or the applicable jurisdiction. If the FDA, EMA or any applicable foreign regulatory authority does not accept such data, it would result in the need for additional trials, which would be costly and time-consuming and delay aspects of our business plan, and which may result in our product candidates not receiving approval or clearance for commercialization in the applicable jurisdiction.

Previous wording

Our sole product candidate is sabirnetug. We may not be able to identify and successfully develop new product candidates in addition to sabirnetug. Even if we are successful in building our product pipeline, the potential product candidates that we identify may not be suitable for clinical development or, if deemed suitable for clinical development, successful in any clinical trials. For example, product candidates may be shown to have harmful side effects or other characteristics that indicate that they are unlikely to be successfully developed, much less receive marketing approval and achieve market acceptance. If we do not successfully develop and commercialize product candidates, we will not be able to obtain product revenue in future periods, which would result in significant harm to our financial position and adversely affect our stock price.

Current wording

Our sole product candidate is sabirnetug. We may not be able to identify and successfully develop new product candidates in addition to sabirnetug. Even if we are successful in building our product pipeline, the potential product candidates that we identify may not be suitable for clinical development or, if deemed suitable for clinical development, may not be successful in any clinical trials. For example, product candidates may be shown to have harmful side effects or other characteristics that indicate that they are unlikely to be successfully developed, much less receive marketing approval and achieve market acceptance. If we do not successfully develop and commercialize product candidates, we will not be able to obtain product revenue in future periods, which would result in significant harm to our financial position and adversely affect our stock price.

Previous wording

As product candidates proceed through nonclinical studies to late-stage clinical trials toward potential approval and commercialization, it is common that various aspects of the development program, such as manufacturing methods and formulation, are altered along the way in an effort to optimize processes and product characteristics. For example, through our CMOs we plan to implement a larger scale sabirnetug manufacturing process with increased yields and at larger scale production levels. We are also developing a lyophilized drug product form and refrigeration-stable formulation as well.

Current wording

As product candidates proceed through nonclinical studies to late-stage clinical trials toward potential approval and commercialization, it is common that various aspects of the development program, such as manufacturing methods and formulation, are altered along the way in an effort to optimize processes and product characteristics. For example, through our contract manufacturing organizations, or CMOs, we plan to implement a larger scale sabirnetug manufacturing process with increased yields and at larger scale production levels. We are also developing a lyophilized drug product form and refrigeration-stable formulation.

Previous wording

•product labeling or product insert requirements of the FDA or other foreign regulatory authorities, including any limitations or warnings contained in a product’s approved labeling, including any black box warning or REMS;

Current wording

•product labeling or product insert requirements of the FDA or other comparable foreign regulatory authorities, including any limitations or warnings contained in a product’s approved labeling, such as any black box warning or REMS;

Previous wording

We do not have sales or marketing infrastructure. To achieve commercial success for sabirnetug or any other product candidate for which we may obtain marketing approval, we will either need to establish a commercial collaboration with a pharmaceutical company that has a sales and marketing organization or we will be required to develop these capabilities internally. There are risks and limitations associated with entering into a commercial collaboration. For example, we may not be successful in entering into arrangements with third parties to sell, market and distribute our product candidates or may be unable to do so on terms that are favorable to us. Even if we are able to enter into a collaboration, our revenue and profitability, if any, are likely to be significantly lower than if we were able to successfully commercialize a product ourselves. In addition, we likely would have little control over such third parties, and any of them may fail to devote the necessary resources and attention to sell and market our products effectively.

Current wording

We do not have a sales or marketing infrastructure. To achieve commercial success for sabirnetug or any other product for which we may obtain marketing approval, we will either need to establish a commercial collaboration with a pharmaceutical company that has a sales and marketing organization or we will be required to develop these capabilities internally. There are risks and limitations associated with entering into a commercial collaboration. For example, we may not be successful in entering into arrangements with third parties to sell, market and distribute our product candidates or may be unable to do so on terms that are favorable to us. Even if we are able to enter into a collaboration, our revenue and profitability, if any, are likely to be significantly lower than if we were able to successfully commercialize a product ourselves. In addition, we likely would have little control over such third parties, and any of them may fail to devote the necessary resources and attention to sell and market our products effectively.