ProMIS Neurosciences Inc.

Previous wording

All references in this management’s discussion and analysis of financial condition and results of operations, or MD&A, to the “Company”, “ProMIS”, “we”, “us”, or “our” refer to ProMIS Neurosciences Inc., unless otherwise indicated or the context requires otherwise. The following MD&A is prepared as of November 10, 2025 for the three and nine months ended September 30, 2025 and should be read in conjunction with the audited consolidated financial statements for the year ended December 31, 2024 and 2023 included in the Company’s Annual Report on Form 10-K and the unaudited condensed consolidated financial statements for the three and nine months ended September 30, 2025 and 2024 included in this Quarterly Report on Form 10-Q (collectively, the “Financial Statements”), which have been prepared by management in accordance with GAAP as issued by the FASB. All dollar amounts refer to United States dollars, except as stated otherwise.

Current wording

All references in this management’s discussion and analysis of financial condition and results of operations, or MD&A, to the “Company”, “ProMIS”, “we”, “us”, or “our” refer to ProMIS Neurosciences Inc., unless otherwise indicated or the context requires otherwise. The following MD&A is prepared as of May 12, 2026 for the three months ended March 31, 2026 and 2025 and should be read in conjunction with the audited consolidated financial statements for the year ended December 31, 2025 and 2024 included in the Company’s Annual Report on Form 10-K and the unaudited condensed consolidated financial statements for the three months ended March 31, 2026 and 2025 included in this Quarterly Report on Form 10-Q (collectively, the “Financial Statements”), which have been prepared by management in accordance with GAAP as issued by the FASB. All dollar amounts refer to United States dollars, except as stated otherwise.

Previous wording

We are applying our patented technology platform to build a portfolio of antibody therapies and therapeutic vaccines in neurodegenerative diseases and other protein-misfolding diseases, with a focus on Alzheimer’s disease (AD), multiple system atrophy (MSA), and amyotrophic lateral sclerosis (ALS). We believe these diseases share a common biologic cause — misfolded versions of proteins, that otherwise perform a normal function, becoming toxic and killing neurons, resulting in disease. ProMIS’ technology platform enables drug discovery through a combination of protein biology, physics and supercomputing. We believe this platform provides a potential advantage in selectively targeting the toxic misfolded proteins with therapeutics or detecting them with diagnostics.

Current wording

We are applying our patented technology platform to build a portfolio of antibody therapies, therapeutic vaccines, and other antibody-based therapies in neurodegenerative diseases and other protein-misfolding diseases, with a focus on Alzheimer’s disease (AD), multiple system atrophy (MSA), and amyotrophic lateral sclerosis (ALS). We believe these diseases share a common biologic cause — misfolded versions of proteins, that otherwise perform a normal function, becoming toxic and killing neurons, resulting in disease. Our technology platform enables drug discovery through a combination of protein biology, physics and supercomputing. We believe this platform provides a potential advantage in selectively targeting the toxic misfolded proteins with therapeutics or detecting them with diagnostics.

Previous wording

We are developing a pipeline of antibodies aimed at selectively targeting misfolded toxic forms of proteins that drive neurodegenerative diseases without interfering with the essential functions of the same properly folded proteins. Our product candidates are PMN310, PMN267, and PMN442. Our lead product candidate is PMN310, a monoclonal antibody designed to treat AD by selectively targeting toxic, misfolded oligomers of amyloid-beta. PMN267 is our second lead product candidate targeting ALS. It has been shown in preclinical studies to selectively recognize misfolded, cytoplasmic TDP-43 aggregates without interacting with normal TDP-43. Misfolded TDP-43 is believed to play an important role in the development of ALS. In light of research suggesting that misfolded toxic alpha-synuclein (a-syn) is a primary driver of disease in synucleinopathies such as MSA and Parkinson’s disease, our third lead product candidate, PMN442 has shown robust binding to pathogenic a-syn oligomers and seeding fibrils in preclinical studies, with negligible binding to a-syn monomers and physiologic tetramers which are required for normal neuronal function. We also have earlier stage preclinical programs and a project to refine our discovery algorithm using machine learning as highlighted in the “Other Key Projects” section below.

Current wording

We are developing a pipeline of antibodies aimed at selectively targeting misfolded toxic forms of proteins that drive neurodegenerative diseases without interfering with the essential functions of the same properly folded proteins. Our product candidates are PMN310, PMN267, and PMN442. The lead product candidate is PMN310, a monoclonal antibody designed to treat AD by selectively targeting toxic, misfolded oligomers of amyloid-beta. PMN267 is our second lead product candidate targeting ALS. It has been shown in preclinical studies to selectively recognize misfolded, cytoplasmic TDP 43 aggregates without interacting with normal TDP 43. Misfolded TDP 43 is believed to play an important role in the development of ALS. In light of research suggesting that misfolded toxic a-syn is a primary driver of disease in synucleinopathies such as MSA and Parkinson’s disease, our third lead product candidate, PMN442, has shown robust binding to pathogenic a-syn oligomers and seeding fibrils in preclinical studies, with negligible binding to a-syn monomers and physiologic tetramers which are required for normal neuronal function.

Previous wording

We were incorporated on January 23, 2004 under the Canada Business Corporations Act (CBCA). On July 13, 2023, we continued our existence from a corporation incorporated under the CBCA into the Province of Ontario under the Business Corporations Act (Ontario) (the OBCA) (the Continuance). The Continuance was approved by our shareholders at our 2023 Annual Meeting of Shareholders held on June 29, 2023. We have a wholly-owned U.S. subsidiary, ProMIS USA, which was incorporated in January 2016 in the State of Delaware. ProMIS USA has had no material activity and has no material financial impact on our Financial Statements. Since our inception, we have devoted substantially all of our resources to developing our platform technologies and the resultant antibody product candidates, building our intellectual property portfolio, business planning, raising capital and providing general and administrative support for these operations. We have principally financed our operations through public and private placements of Common Shares and warrants and convertible debt.

Current wording

We were incorporated on January 23, 2004 under the Canada Business Corporations Act (“CBCA”). On July 13, 2023, we continued our existence from a corporation incorporated under the CBCA into the Province of Ontario under the Business Corporations Act (Ontario) (“OBCA”) (“Continuance”). The Continuance was approved by our shareholders at our 2023 Annual Meeting of Shareholders held on June 29, 2023. We are located at 1920 Yonge Street, Toronto, Ontario. Our Common Shares are traded on the Nasdaq Capital Market (“Nasdaq”) under the symbol PMN. We have a wholly-owned U.S. subsidiary, ProMIS Neurosciences (U.S.) Inc. (“ProMIS USA”), which was incorporated in January 2016 in the State of Delaware. As of March 31, 2026, ProMIS USA has had no material activity and has no material financial impact on the Company’s consolidated financial statements.

Previous wording

We have incurred significant operating losses since inception. Our ability to generate product revenue sufficient to achieve profitability will depend heavily on the successful development and eventual licensing and/or commercialization of our product candidates and any future product candidates. Our operating losses were $11.8 million and $4.4 million for the three months ended September 30, 2025 and 2024, respectively, and $29.4 million and $10.8 million for the nine months ended September 30, 2025 and 2024, respectively. As of September 30, 2025, we had an accumulated deficit of $119.7 million. We had negative cash flows from operations of $18.8 million for the nine months ended September 30, 2025.

Current wording

We have incurred significant operating losses since inception. Our ability to generate product revenue sufficient to achieve profitability will depend heavily on the successful development and eventual commercialization of our product candidates and any future product candidates. We had an operating loss of $8.6 million and $7.5 million for the three months ended March 31, 2026 and 2025, respectively. As of March 31, 2026, we had an accumulated deficit of $138.7 million. We had negative cash flows from operations of $10.6 million for the three months ended March 31, 2026.

Previous wording

In July 2025, we received gross proceeds of $21.6 million from discounted warrant exercises, the sale of additional warrants in private placements, and the sale of pre-funded warrants to purchase Common Shares in a registered direct offering, less transaction costs of $1.4 million. Refer to additional discussion in Note 6. However, we expect to continue to incur net losses for the foreseeable future and, if able to raise additional funding, would expect our research and development expenses, general and administrative expenses and capital expenditures to increase. In particular, if we are able to raise additional funding, we expect our expenses to increase as we continue our development of, and seek regulatory approvals for, our product candidates, as well as initiate clinical trials, hire additional personnel, pay fees to outside consultants, lawyers and accountants, and incur other increased costs associated with being a clinical-stage public company. In addition, if we obtain marketing approval for any product candidates, we may incur significant commercialization expenses related to product manufacturing, marketing, sales and distribution. We may also incur expenses should we in-license or acquire additional product candidates.

Current wording

However, we expect to continue to incur losses for the foreseeable future and, if able to raise additional funding, would expect our research and development expenses, general and administrative expenses and capital expenditures to increase. In particular, if we are able to raise additional funding we expect our expenses to increase as we continue our development of, and seek regulatory approvals for, our product candidates, as well as continue and initiate new clinical trials, hire additional personnel, and pay fees to outside consultants, lawyers and accountants. In addition, if we obtain marketing approval for any product candidates, we may incur significant

Previous wording

PRECISE-AD is a randomized, double-blind, placebo-controlled, multiple ascending dose (“MAD”) study of PMN310 to evaluate safety, tolerability, pharmacokinetics (“PK”), pharmacodynamics, and preliminary efficacy of multiple intravenous infusions of PMN310 in patients with early AD. The study will also evaluate key biomarkers and clinical measures of efficacy to gather data on PMN310’s therapeutic potential. PRECISE-AD plans to enroll approximately 100 subjects across 22 active sites in the United States. Eligible patients will be dosed monthly at one of three dose levels (5, 10, 20 mg/kg) or placebo over 12 months with assessment of safety, tolerability, PK, and pharmacodynamic blood-and brain-based markers of treatment effect at baseline and every three months. Frequent MRI scans will be conducted throughout to monitor for any emergence of amyloid-related imaging abnormalities (“ARIA”).

Current wording

PMN310, a monoclonal antibody selective for toxic amyloid-beta oligomers in AD, is our lead product candidate. We successfully completed our Phase 1a clinical trial with PMN310 and commenced our Phase 1b clinical trial (“PRECISE-AD”) in December 2024. In July 2025, PMN310 was granted Fast Track designation by the FDA. The ongoing PRECISE-AD trial is a randomized, double-blind, placebo-controlled, MAD study of PMN310 to evaluate safety, tolerability, pharmacokinetics (PK), pharmacodynamics, and preliminary efficacy of multiple intravenous infusions of PMN310 in patients with early Alzheimer's disease. The study will also evaluate key biomarkers and clinical measures of efficacy to gather data on PMN310’s therapeutic potential. Enrollment in the PRECISE-AD study was completed in December 2025 with 144 subjects enrolled across 21 active sites in the United States. The subjects are dosed monthly at one of three dose levels (5, 10, 20 mg/kg) or placebo over 12 months with assessment of safety, tolerability, PK, and pharmacodynamic blood-and CSF-based biomarkers of treatment effect at baseline and every three months. Frequent MRI scans throughout the study are being conducted to monitor for any emergence of ARIA.

Previous wording

Safety will be a primary outcome with particular emphasis on assessing the expectation that, as a non-plaque binder, PMN310 will have a reduced risk of ARIA compared to other Ab-directed antibodies. PRECISE-AD is expected to provide 95% confidence for detection of ARIA. The study has been designed with a sample size intended to provide sufficient power to provide meaningful insight into effects of PMN310 on biomarkers of disease and clinical outcomes. PRECISE-AD will be the first study to examine the effects of a monoclonal antibody directed solely against Aβ oligomers on biomarkers associated with AD pathology and clinical outcomes.

Current wording

Safety will be a primary outcome with particular emphasis on assessing the expectation that, as a non-plaque binder, PMN310 will have a reduced risk of ARIA. The study is powered to provide 95% confidence for detection of ARIA. The study has been designed with a sample size intended to provide sufficient power to provide meaningful insight into effects of PMN310 on biomarkers and clinical outcomes. PRECISE-AD will be the first study to examine the effects of a monoclonal antibody directed solely against toxic Aβ oligomers on biomarkers associated with AD pathology and clinical outcomes.

Previous wording

Expenditures for PMN310 in the three and nine months ended September 30, 2025, were approximately $8.8 million and $21.5 million, respectively, not including allocations of senior management time.

Current wording

Expenditures for PMN310 in the three months ended March 31, 2026 were approximately $6.3 million, not including allocations of senior management time.

Previous wording

PMN267 has been humanized in a human IgG1 framework and is ready to progress to IND-enabling studies, subject to sufficient available resources, to support the systemic, extracellular administration form. Additionally, in conjunction with a partner having expertise with vectorization, the development of an intrabody form could progress.

Current wording

PMN267 has been humanized in a human IgG1 framework for IND-enabling studies to support the systemic, extracellular administration form. Development of the intrabody form would involve collaboration with a partner with expertise in viral vectorization.

Previous wording

ProMIS has selected a novel monoclonal antibody (PMN442) as a lead candidate for MSA and other synucleinopathies based on its selective binding and protective activity against pathogenic forms of alpha-synuclein. PMN442 has been humanized in a human IgG1 framework and is ready to progress to IND-enabling studies, subject to availability of sufficient resources.

Current wording

ProMIS has selected a novel monoclonal antibody (PMN442) as a lead candidate for Dementia with Lewy bodies and other synucleinopathies based on its selective binding and protective activity against pathogenic forms of alpha-synuclein. PMN442 has been humanized in a human IgG1 framework for advancement to IND-enabling studies.

Previous wording

We continue to progress with other key projects, in addition to our top priorities PMN310, PMN267, and PMN442. With respect to the amyloid vaccine program, mouse studies have provided data guiding the development of an AD vaccine against toxic Aβ oligomers leading to the selection of a lead candidate, PMN311, consisting of a dominant conformational peptide epitope conjugated to a carrier protein in formulation with an adjuvant. Similarly, mouse vaccination studies with a-syn vaccine candidates utilizing our peptide antigens to target pathogenic a-syn enabled the selection of our lead vaccine candidate, PMN400, against multiple synucleinopathies including MSA, Parkinson’s disease and Lewy body dementia. Assessment of the protective activity of the vaccine in mouse models of synucleinopathies is ongoing.

Current wording

We continue to progress with other key projects, in addition to our top priorities PMN310, PMN267, and PMN442. With respect to the amyloid vaccine program, mouse studies have provided data guiding the development of an AD vaccine against toxic Aβ oligomers leading to the selection of a lead candidate, PMN311, consisting of a dominant conformational peptide epitope conjugated to a carrier protein in formulation with an adjuvant. Mouse vaccination studies with a-syn vaccine candidates utilizing our peptide antigens to target pathogenic a-syn enabled the selection of our lead vaccine candidate, PMN400, against multiple synucleinopathies including MSA, Parkinson’s disease and Lewy body dementia. Assessment of the protective activity of the vaccine in mouse models of synucleinopathies is ongoing. Similarly, a vaccine candidate comprising a misfolded TDP-43 epitope (PMN260) has shown robust immunogenicity in mouse vaccination studies.

Previous wording

Our proprietary technology employs computational algorithmic prediction of protein misfolding to identify disease-specific epitopes (DSEs) to which selective antibodies can be raised. An effort is underway to update the algorithms with machine learning capabilities to accelerate our ability to identify and patent DSEs and antibodies, across neurodegenerative diseases as well as other therapeutic areas.

Current wording

Our proprietary technology, EpiSelect TM, employs computational algorithmic prediction of protein misfolding to identify disease-specific epitopes (DSEs) to which selective antibodies can be raised. An effort is underway to update the algorithms with machine learning capabilities to accelerate our ability to identify and patent DSEs and antibodies, across neurodegenerative diseases as well as other therapeutic areas.

Previous wording

We enter into consulting, research, and other agreements with commercial entities, researchers, universities, and others for the provision of goods and services. Such arrangements are generally cancelable upon reasonable notice and payment of costs incurred. Costs are considered incurred based on an evaluation of the progress to completion of specific tasks under each contract using information and data provided by the respective vendors, including our clinical sites. These costs consist of direct and indirect costs associated with our platform technologies, as well as fees paid to various entities that perform certain research on our behalf. Depending upon the timing of payments to the service providers, we recognize prepaid expenses or accrued expenses related to these costs. These accrued or prepaid expenses are based on management’s estimates of the work performed under service agreements, milestones achieved, and experience with similar contracts. We monitor each of these factors and adjust estimates accordingly.

Current wording

We enter into consulting, research, and other agreements with commercial entities, researchers, universities, and others for the provision of goods and services. Such arrangements are generally cancelable upon reasonable notice and payment of costs incurred. Costs are considered incurred based on an evaluation of the progress to completion of specific tasks under each contract using information and data provided by the respective vendors, including our clinical sites. These costs consist of direct and indirect costs associated with our

Previous wording

Research and development expenses increased by $7.2 million, or 282%, for the three months ended September 30, 2025 compared to the three months ended September 30, 2024. This increase is largely attributable to a $6.9 million increase in direct research and development expenses related to the PMN310 phase 1b trial, which commenced in late 2024 and is ongoing in 2025. Employee salary and benefit costs also increased by $0.3 million.

Current wording

Research and development expenses increased by $1.5 million, or 28%, for the three months ended March 31, 2026 compared to the three months ended March 31, 2025. This increase was due to increased activity in the ongoing PMN310 phase 1b trial in the three months ended March 31, 2026 compared to the three months ended March 31, 2025. Consulting expense decreased by $0.1 million.

Previous wording

General and administrative expenses increased by $0.9 million, or 31%, for the nine months ended September 30, 2025 compared to the nine months ended September 30, 2024. Employee salaries and benefits increased by $0.9 million due to the recognition of $0.5 million in severance costs during the nine months ended September 30, 2025 and the hiring of additional employees in 2025. Professional and consulting fees decreased by $0.5 million, primarily driven by a decrease of $0.3 million in investor and shareholder relations costs, $0.2 million in insurance costs, and $0.1 million in legal fees, offset by an increase of $0.1 million in recruiting costs. Share-based compensation expense increased by $0.3 million. Facility-related and other costs increased by $0.2 million.

Current wording

General and administrative expenses decreased by $0.3 million, or 16%, for the three months ended March 31, 2026 compared to the three months ended March 31, 2025. Employee salaries and benefits decreased by $0.3 million due to the recognition of $0.5 million in severance costs during the three months ended March 31, 2025, offset by additional employees in the three months ended March 31, 2026. Share-based compensation expense decreased by $0.1 million, offset by a $0.1 million increase in patent expense.

Previous wording

We are a development stage company as we have not generated revenues to date and do not expect to have significant revenues until we are able to sell a product candidate after obtaining applicable regulatory approvals or we establish collaborations that provide funding, such as licensing fees, milestone payments, royalties, research funding or otherwise. Operations have been financed since inception, through the sale of equity and debt securities and the conversion of Common Share purchase warrants and share options. Our objectives, when managing capital, are to ensure there are sufficient funds available to carry out our research, development and eventual commercialization programs. When we have excess funds, we manage our liquidity risk by investing in highly liquid corporate and government bonds with staggered maturities to provide regular cash flow for current operations. We do not hold any asset-backed commercial paper, and our cash is not subject to any external restrictions. We also manage liquidity risk by frequently monitoring actual and projected cash flows. The Board reviews and approves the Company’s operating and capital budgets, as well as any material transactions not in the ordinary course of business. The majority of our accounts payable and accrued liabilities have maturities of less than three months. We are dependent on our ability to generate revenues from our products or secure additional financing in order to continue our research and development activities and meet our ongoing obligations and existing liabilities.

Current wording

We are a development stage company as we have not generated revenues to date and do not expect to have significant revenues until we are able to sell a product candidate after obtaining applicable regulatory approvals or we establish collaborations that provide funding, such as licensing fees, milestone payments, royalties, research funding or otherwise. Operations have been financed since inception, through the sale of equity and debt securities and the conversion of Common Share purchase warrants and share options. Our objectives, when managing capital, are to ensure there are sufficient funds available to carry out our research, development and eventual commercialization programs. When we have excess funds, we manage our liquidity risk by investing in highly liquid corporate and government bonds with staggered maturities to provide regular cash flow for current operations. We do not hold any asset-backed commercial paper and our cash is not subject to any external restrictions. We also manage liquidity risk by frequently monitoring actual and projected cash flows. The Board reviews and approves the Company’s operating and capital budgets, as well as any material transactions not in the ordinary course of business. The majority of our accounts payable and accrued liabilities have maturities of less

Previous wording

We incurred a net loss of $11.8 million and $29.4 million for the three and nine months ended September 30, 2025, respectively. We reported an accumulated deficit of $119.7 million as of September 30, 2025, and had negative cash flows from operations of $18.8 million for the nine months ended September 30, 2025. Management believes that these conditions raise substantial doubt as to the Company’s ability to continue as a going concern within 12 months of the date the Financial Statements are issued. Additional funding will be necessary to fund future clinical activities and to pay down our existing liabilities. We will seek additional funding through public and private financings, debt financings, collaboration agreements, strategic alliances and licensing agreements. Although we have been successful in raising capital in the past, changing macroeconomic factors including, but not limited to, rising interest rates, uncertainties in the banking industry and inflation have diminished certain opportunities to obtain funding in the current market environment. There is no assurance of success in obtaining such additional financing on terms acceptable to us, if at all, and there is no assurance that we will be able to enter into collaborations or other arrangements. If we are unable to obtain funding, it could force us to delay, reduce or eliminate research and development programs and product portfolio expansion or commercialization efforts. These potential delays, reductions and eliminations could adversely affect future business prospects, and our ability to continue as a going concern.

Current wording

Additional funding will be necessary to fund future clinical activities and to pay down our existing liabilities. We will seek additional funding through public and private financings, debt financings, collaboration agreements, strategic alliances and licensing agreements. Although we have been successful in raising capital in the past, changing macroeconomic factors including, but not limited to, rising interest rates, uncertainties in the banking industry and inflation have diminished certain opportunities to obtain funding in the current market environment. There is no assurance of success in obtaining such additional financing on terms acceptable to us, if at all, and there is no assurance that we will be able to enter into collaborations or other arrangements. If we are unable to obtain funding, it could force us to delay, reduce or eliminate research and development programs and product portfolio expansion or commercialization efforts. These potential delays, reductions and eliminations could adversely affect future business prospects, and our ability to continue as a going concern.

Previous wording

Cash used in operating activities was $18.8 million for the nine months ended September 30, 2025, which consisted of a net loss of $29.0 million, decreased by share-based compensation of $0.7 million and a net change of $9.6 million in our operating assets and liabilities. Changes in cash flows related to operating assets and liabilities primarily consisted of an increase of $7.5 million of accrued liabilities, an increase of $2.5 million of accounts payable, and an increase of $0.4 million in prepaid expenses and other current assets.

Current wording

Cash used in operating activities was $12.4 million for the three months ended March 31, 2026, which consisted of a net loss of $8.2 million, decreased by share-based compensation of $0.2 million, and a net change of $4.3 million in our operating assets and liabilities. Changes in cash flows related to operating assets and liabilities primarily consisted of a decrease of $3.0 million of accrued liabilities, a decrease of $0.8 million of accounts payable and an increase of $0.5 million of prepaid expenses and other assets.

Previous wording

Cash used in operating activities was $18.5 million for the nine months ended September 30, 2024, which consisted ofnet income of $3.0 million, decreased by non-cash activities of $13.3 million and a net change of $8.2 million in our operating assets and liabilities. Non-cash decreases included gains of $17.0 million on the change in the fair value of our financial instruments, offset by a non-cash loss of $3.5 million on the issuance of our Common Shares, warrants and pre-funded warrants in the July 2024 PIPE, and $0.2 million of share-based compensation. Changes in cash flows related to operating assets and liabilities primarily consisted of a decrease of $6.3 million of accounts payable, including a repayment of $5.9 million on previously deferred accounts payable, a $0.4 million decrease in accrued liabilities, and a $1.5 million increase in prepaid expenses and other current assets.

Current wording

Cash used in operating activities was $4.9 million for the three months ended March 31, 2025, which consisted of a net loss of $7.3 million, decreased by share-based compensation of $0.2 million and a net change of $2.2 million in our operating assets and liabilities. Changes in cash flows related to operating assets and liabilities primarily consisted of an increase of $2.4 million of accrued liabilities and a decrease of $0.3 million of prepaid expenses, offset by a decrease of $0.5 million of accounts payable.

Previous wording

There was no cash used in investing activities during the nine months ended September 30, 2025 or 2024.

Current wording

There was no cash provided by financing activities during the three months ended March 31, 2025.

Previous wording

The number of issued and outstanding Common Shares and Common Share Equivalents as of September 30, 2025 was as follows:

Current wording

The number of issued and outstanding Common Share Equivalents as of March 31, 2026 was as follows: