ACI-7104

AC Immune Reports Positive Interim Results from Phase 2 Trial of ACI-7104.056 Active Immunotherapy in Early Parkinson’s Disease Active immunotherapy with ACI-7104.056 induces high anti-a-synuclein antibody levels on average 16-fold higher than placebo after 3 immunizations100% of patients receiving ACI-7104.056 responded against the target antigenACI-7104.056 is well tolerated with no clinically relevant safety issues reported to date Lausanne, Switzerland, November 14, 2024 – AC Immune SA (NASDAQ: ACIU), a clinical-stage biopharmaceutical company pioneering precision therapeutics for neurodegenerative diseases, today announced positive interim safety and immunogenicity data from the Phase 2 VacSYn clinical trial evaluating ACI-7104.056, its wholly owned anti-alpha-synuclein (a-syn) active immunotherapy candidate, for the treatment of patients with early Parkinson’s disease (PD). Dr. Andrea Pfeifer, CEO of AC Immune SA, commented: “We are encouraged by these initial Phase 2 safety and immunogenicity data on our ACI-7104.056 active immunotherapy being studied in early Parkinson’s disease. The level of immunogenicity after only 3 months of treatment as well as the continued positive safety profile, reinforces the best-in-class characteristics of our clinically validated anti-a-syn active immunotherapy for the treatment of Parkinson’s disease. We look forward to sharing further updates in H1 2025 including the decision to expand into Part 2 of the VacSYn study.” Dr. Pfeifer added, “As a leader in active immunotherapies for neurodegenerative diseases with two FDA Fast Track designated candidates, an important recognition of their promise, we are delighted with these initial VacSYn data. They further support the approach of using active immunotherapies to target the hallmark pathological proteins of neurodegenerative diseases, such as a-synuclein in Parkinson’s disease, before irreversible damage occurs.” VacSYn is an adaptive, placebo-controlled, and biomarker-based Phase 2 study in patients with early PD, consisting of two parts with a seamless transition. Part 1 includes initial analyses from over 30 patients randomized to receive ACI-7104.56 or placebo at a ratio of 3:1. To date, no clinically relevant safety issues have been reported other than transient injection site reactions (49%) and headaches (18%). Interim results show positive antibody responses were effectively induced against the target antigen at week 6 after 2 immunizations and were strongly boostable. Treatment with ACI-7104.056 induced an increase in anti-a-syn antibodies on average 16-fold higher than the placebo background level after three immunizations. Based on further interim results to be reported in H1 2025 including pharmacodynamic data, AC Immune may decide to initiate Part 2 of VacSYn with up to 150 patients. Patients from Part 2 will also be evaluated for progression of motor and non-motor symptoms of the disease, as well as digital, imaging, and fluid biomarkers. The aim is to establish early proof-of-concept and identification of disease-specific biomarkers for rapid transition into a pivotal study. About ACI-7104.056ACI-7104.056 is an optimized formulation of its clinically validated anti-a-syn predecessor active immunotherapy which generated a target-specific antibody response against pathological oligomeric a-syn to inhibit spreading and downstream neurodegeneration in early Parkinson’s disease. The accumulation of alpha-synuclein protein aggregates has been shown to cause inflammatory stress in cells and contribute to the degeneration of neurons in the brain. It has been known to play a key role in the development of neurodegenerative diseases such as Parkinson’s Disease. Previous clinical studies showed the predecessor candidate produced a strong and boostable antibody response with evidence of target engagement and a signal of clinical efficacy. About AC Immune SA AC Immune SA is a clinical-stage biopharmaceutical company and a global leader in precision prevention for neurodegenerative diseases, including Alzheimer’s disease, Parkinson’s disease, and NeuroOrphan indications driven by misfolded proteins. The Company’s two clinically validated technology platforms, SupraAntigen® and Morphomer®, fuel its broad and diversified pipeline of first- and best-in-class assets, which currently features sixteen therapeutic and diagnostic programs, including five in Phase 2 development and one in Phase 3. AC Immune has a strong track record of securing strategic partnerships with leading global pharmaceutical companies, resulting in substantial non-dilutive funding to advance its proprietary programs and >$4.5 billion in potential milestone payments plus royalties. SupraAntigen® is a registered trademark of AC Immune SA in the following territories: AU, EU, CH, GB, JP, RU, SG and USA. Morphomer® is a registered trademark of AC Immune SA in CN, CH, GB, JP, KR, NO and RU. The information on our website and any other websites referenced herein is expressly not incorporated by reference into, and does not constitute a part of, this press release. For further information, please contact: Head of Investor Relations & Corporate CommunicationsGary Waanders, Ph.D., MBAAC ImmunePhone: +41 21 345 91 91Email: gary.waanders@acimmune.comU.S. InvestorsChristina TartagliaPrecision AQPhone: +1 212 362 1200 Email: christina.tartaglia@precisionaq.com International MediaChris MaggosCohesion BureauPhone: +41 79 367 6254Email: chris.maggos@cohesionbureau.com Forward looking statementsThis press release contains statements that constitute “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. Forward-looking statements are statements other than historical fact and may include statements that address future operating, financial or business performance or AC Immune’s strategies or expectations. In some cases, you can identify these statements by forward-looking words such as “may,” “might,” “will,” “should,” “expects,” “plans,” “anticipates,” “believes,” “estimates,” “predicts,” “projects,” “potential,” “outlook” or “continue,” and other comparable terminology. Forward-looking statements are based on management’s current expectations and beliefs and involve significant risks and uncertainties that could cause actual results, developments and business decisions to differ materially from those contemplated by these statements. These risks and uncertainties include those described under the captions “Item 3. Key Information – Risk Factors” and “Item 5. Operating and Financial Review and Prospects” in AC Immune’s Annual Report on Form 20-F and other filings with the Securities and Exchange Commission. Forward-looking statements speak only as of the date they are made, and AC Immune does not undertake any obligation to update them in light of new information, future developments or otherwise, except as may be required under applicable law. All forward-looking statements are qualified in their entirety by this cautionary statement. Attachment 20241114_ACIU_VacSYn Interim-Final-CLEAN

AC Immune Reports Second Quarter 2024 Financial Results and Provides a Corporate Update Announced exclusive option and license agreement with Takeda for ACI-24.060 on May 13 for $100 million upfront and total potential milestones of up to approximately $2.1 billionACI-24.060 ABATE Phase 2 trial in Alzheimer’s disease (AD) on track with enrolment expectationsACI-7104.056 VacSYn Phase 2 trial of anti-a-syn active immunotherapy in Parkinson’s disease (PD) on track for safety and immunogenicity interim data in H2 2024Potent inhibitor of the inflammatory NLRP3 pathway, ACI-19764, demonstrates promising preclinical results and may be broadly applicable to treat CNS and non-CNS diseasesCash balance of CHF 175.2 million at quarter end, including CHF 92.3 million from Takeda, provides sufficient runway for three years Lausanne, Switzerland, August 6, 2024 – AC Immune SA (NASDAQ: ACIU), a clinical-stage biopharmaceutical company pioneering precision therapeutics for neurodegenerative diseases, today reported results for the quarter ended June 30, 2024, and provided a corporate update. Dr. Andrea Pfeifer, CEO of AC Immune SA, commented, “AC Immune is entering the second half of 2024 with tremendous momentum. We are excited about the recently announced partnership with Takeda for ACI-24.060 as a potential best-in-class Abeta-targeted active immunotherapy. Enrollment in the ABATE Phase 2 trial of ACI-24.060 in AD continues to progress as planned.” “We are also excited to be advancing our preclinical programs, some of which were recently featured in multiple presentations at the AAIC 2024 conference. Our novel morADC platform, a synergistic combination of our SupraAntigen® and Morphomer® platforms, has significant potential for enhanced targeted interventions for a variety of neurodegenerative diseases and also offers opportunities for simultaneous combination approaches. These morADCs are already showing promise in multiple preclinical models, and we look forward to sharing more details on this and on other preclinical development programs in an upcoming R&D day. Our solid financial position, enhanced by the Takeda partnership, enables us to drive clinical and preclinical development, leveraging the core competency of AC Immune that is anchored by our foundational expertise in neurodegenerative disease drug discovery.” Q2 2024 and Subsequent Highlights AC Immune and Takeda signed an exclusive option and license agreement for AC Immune’s active immunotherapies targeting Abeta, including ACI-24.060 for AD. Under the terms of the agreement, AC Immune received an upfront payment of $100 million from Takeda and, if all related milestones are achieved over the course of the agreement, is eligible to receive payments of up to approximately $2.1 billion including an option exercise fee and additional potential development, commercial and sales-based milestones. Upon commercialization, AC Immune will be entitled to receive tiered double-digit royalties on worldwide net sales.Enrolment in the ACI-24.060 ABATE Phase 2 AD trial continues.We also completed the regulatory toxicology studies for the anti-TDP-43 monoclonal antibody candidate in Q2 which will enable us to proceed with IND filing.Our targeted NLRP3 inhibitor candidates continue to show excellent promise in preclinical results featured at the AD/PD™ 2024 conference: ACI-19764 is a brain penetrant small molecule in preclinical development that directly binds and inhibits NLRP3. Its activity in vitro and in vivo was demonstrated in two models of neuroinflammation. In addition, ACI-19764 demonstrated an excellent safety profile and optimal exposure for sustained NLRP3 inhibition in the brain.AC Immune intends to file an IND from the NLRP3 program in the near future. AC Immune’s preclinical programs were featured in multiple presentations at the Alzheimer’s Association International Conference (AAIC) 2024: A new class of neurodegenerative disease-fighting drugs: morADC (Morphomer®- antibody drug conjugates), presented by Madiha Derouazi (Chief Scientific Officer, AC Immune), featured data from AC Immune’s proprietary morADC platform. Results demonstrated the ability of morADCs to penetrate the blood brain barrier in vivo and produce potent catalytic activity in vitro compared to the parental monoclonal antibody or small molecule alone.Active immunotherapy, ACI-24.060, induces anti-Abeta antibodies with binding profiles mirroring clinically validated monoclonal antibodies, presented by Emma Fiorini (AC Immune), featured results from non-human primates demonstrating that ACI-24.060 induced antibody responses in a similar range of levels of donanemab and lecanemab and with preferential oligomeric Abeta binding as compared to monomeric Abeta.Discovery and preclinical development of [18F]ACI-19626, a first-in-class TDP-43 PET tracer, presented by Tamara Seredenina (AC Immune), described the selection of [18F]ACI-19626 for evaluation as a potential PET tracer for detection and monitoring progression of TDP-43 aggregates based on its favorable affinity, selectivity and pharmacokinetic properties. Board and Management Share Purchases: Members of the Board of Directors and certain members of executive management purchased shares in AC Immune SA during Q2 2024, following the announcement of the exclusive option and license agreement with Takeda for ACI-24.060. As a foreign private issuer (FPI), individual shareholdings will be disclosed in the Annual Report on Form 20-F. Anticipated 2024 Milestones ACI-24.060anti-Abeta active immunotherapy ABATE Phase 2 trial in AD on track with enrolment expectations ACI-7104.056anti-a-syn active immunotherapy Interim safety and immunogenicity update from the Phase 2 VacSYn study in Parkinson’s disease expected in H2 2024 ACI-35.030anti-pTau active immunotherapy First patient treated in ReTain Phase 2b clinical trial expected in the coming months TDP-43-PET tracer Phase 1 initiation expected in H2 2024 ACI-15916 a-syn-PET tracer IND-enabling studies in PD expected to be completed in H2 2024 Analysis of Financial Statements for the Quarter Ended June 30, 2024 Cash Position: The Company had a total cash balance of CHF 175.2 million (CHF 103.1 million as of December 31, 2023), composed of CHF 51.6 million in cash and cash equivalents and CHF 123.6 million in short-term financial assets. The Company’s cash balance provides sufficient capital resources for three years, assuming the potential milestone payment of CHF 24.6 million related to achieving an undisclosed enrolment target for our ACI-35.030, and no other milestones.Contract Revenues: The Company recorded CHF 0.7 million in contract revenues for the three months ended June 30, 2024, compared to nil in the comparable prior period. For the three months ended June 30, 2024, our contract revenues of CHF 0.7 million were related to the efforts made under the agreement with Takeda.R&D Expenditures: R&D expenses for the three months ended June 30, 2024, were CHF 17.1 million compared to CHF 13.7 million in the comparable period in 2023. The increase was due mainly to higher clinical expenses, driven by the ramp-up activities for our Phase 2 VacSYn study evaluating ACI-7104.056 in early PD and for the expansion of the ABATE study in our ACI-24.060 active immunotherapy.G&A Expenditures: G&A increased by CHF 0.9 million to CHF 4.6 million, mostly due to an increase in legal fees related to business development and licensing activities, as well as salaries and related costs, largely attributable to the higher expenses from equity awards granted in 2024, which have a higher fair value based on our share price development.Other Operating Income: The Company recognized less than CHF 0.1 million in grant income from Target ALS grants.IFRS Loss for the Period: The Company reported a net loss after taxes of CHF 22.8 million for the three months ended June 30, 2024, compared with a net loss of CHF 16.8 million for the comparable period in 2023. About AC Immune SA AC Immune SA is a clinical-stage biopharmaceutical company and a global leader in precision prevention for neurodegenerative diseases, including Alzheimer’s disease, Parkinson’s disease, and NeuroOrphan indications driven by misfolded proteins. The Company’s two clinically validated technology platforms, SupraAntigen® and Morphomer®, fuel its broad and diversified pipeline of first- and best-in-class assets, which currently features sixteen therapeutic and diagnostic programs, including five in Phase 2 development and one in Phase 3. AC Immune has a strong track record of securing strategic partnerships with leading global pharmaceutical companies, resulting in substantial non-dilutive funding to advance its proprietary programs and >$4.5 billion in potential milestone payments plus royalties. SupraAntigen® is a registered trademark of AC Immune SA in the following territories: AU, EU, CH, GB, JP, RU, SG and USA. Morphomer® is a registered trademark of AC Immune SA in CN, CH, GB, JP, KR, NO and RU. The information on our website and any other websites referenced herein is expressly not incorporated by reference into, and does not constitute a part of, this press release. For further information, please contact: SVP, Investor Relations & Corporate CommunicationsGary Waanders, Ph.D., MBAAC ImmunePhone: +41 21 345 91 91Email: gary.waanders@acimmune.comU.S. InvestorsCorey Davis, Ph.D.LifeSci AdvisorsPhone: +1 212 915 2577 Email: cdavis@lifesciadvisors.comInternational MediaChris MaggosCohesion BureauPhone: +41 79 367 6254Email: chris.maggos@cohesionbureau.com Forward looking statementsThis press release contains statements that constitute “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. Forward-looking statements are statements other than historical fact and may include statements that address future operating, financial or business performance or AC Immune’s strategies or expectations. In some cases, you can identify these statements by forward-looking words such as “may,” “might,” “will,” “should,” “expects,” “plans,” “anticipates,” “believes,” “estimates,” “predicts,” “projects,” “potential,” “outlook” or “continue,” and other comparable terminology. Forward-looking statements are based on management’s current expectations and beliefs and involve significant risks and uncertainties that could cause actual results, developments and business decisions to differ materially from those contemplated by these statements. These risks and uncertainties include those described under the captions “Item 3. Key Information – Risk Factors” and “Item 5. Operating and Financial Review and Prospects” in AC Immune’s Annual Report on Form 20-F and other filings with the Securities and Exchange Commission. Forward-looking statements speak only as of the date they are made, and AC Immune does not undertake any obligation to update them in light of new information, future developments or otherwise, except as may be required under applicable law. All forward-looking statements are qualified in their entirety by this cautionary statement. Condensed Consolidated Balance Sheets (Unaudited)(In CHF thousands) As of June 30, December 31, 2024 2023Assets Non-current assets Property, plant and equipment 2,926 3,376Right-of-use assets 3,235 3,508Intangible asset 50,416 50,416Long-term financial assets 415 361Total non-current assets 56,992 57,661Current assets Prepaid expenses 3,864 6,437Accrued income 402 246Other current receivables 1,153 622Accounts receivable — 14,800Short-term financial assets 123,560 24,554Cash and cash equivalents 51,564 78,494Total current assets 180,543 125,153Total assets 237,535 182,814 Shareholders' equity and liabilities Shareholders’ equity Share capital 2,212 2,089Share premium 476,074 474,907Treasury shares (218) (105)Currency translation differences (35) (51)Accumulated losses (354,608) (316,197)Total shareholders’ equity 123,425 160,643 Non-current liabilities Long-term deferred contract revenue 5,170 —Long-term lease liabilities 2,542 2,825Net employee defined benefit liabilities 5,868 5,770Total non-current liabilities 13,580 8,595 Current liabilities Trade and other payables 1,435 1,679Accrued expenses 11,895 11,087Short-term deferred income 45 138Short-term deferred contract revenue 86,468 —Short-term lease liabilities 687 672Total current liabilities 100,530 13,576Total liabilities 114,110 22,171Total shareholders’ equity and liabilities 237,535 182,814 Condensed Consolidated Statements of Income/(Loss) (Unaudited)(In CHF thousands, except for per-share data) For the Three Months For the Six Months Ended June 30, Ended June 30, 2024 2023 2024 2023Revenue Contract revenue 687 — 687 —Total revenue 687 — 687 — Operating expenses Research & development expenses (17,138) (13,682) (32,303) (27,555)General & administrative expenses (4,551) (3,681) (9,522) (7,787)Other operating income/(expense), net 41 317 109 725Total operating expenses (21,648) (17,046) (41,716) (34,617)Operating loss (20,961) (17,046) (41,029) (34,617) Financial income 739 259 1,368 468Financial expense (34) (27) (70) (124)Exchange differences (2,504) (16) (891) (67)Finance result, net (1,799) 216 407 277 Loss before tax (22,760) (16,830) (40,622) (34,340)Income tax expense — (3) — (6)Loss for the period (22,760) (16,833) (40,622) (34,346)Loss per share: (0.23) (0.20) (0.41) (0.41) Condensed Consolidated Statements of Comprehensive Income/(Loss) (Unaudited)(In CHF thousands) For the Three Months For the Six Months Ended June 30, Ended June 30, 2024 2023 2024 2023Loss for the period (22,760) (16,833) (40,622) (34,346)Items that will be reclassified to income or loss in subsequent periods (net of tax): Currency translation differences — (8) 16 (16)Items that will not to be reclassified to income or loss in subsequent periods (net of tax): Remeasurement gains on defined-benefit plans — — — —Total comprehensive loss (net of tax) (22,760) (16,841) (40,606) (34,362) Attachment 20240805_ACIU_Q2_Earnings_Final