AC Immune to Regain Global Rights to Crenezumab and Semorinemab Company's strategy is focused on advancing the Phase 2 development of its three active immunotherapies Active immunotherapy now considered to

AC Immune to Regain Global Rights to Crenezumab and Semorinemab

Switzerland, January 22, 2024 - AC Immune SA (NASDAQ: ACIU), a clinical-stage biopharmaceutical company pioneering precision

medicine for neurodegenerative diseases, today announced that the Company will

regain all global rights to the anti-amyloid beta antibody crenezumab and the anti-Tau antibody semorinemab following termination

of the collaboration agreements with Genentech, a member of the Roche Group, and Roche. Both antibodies have been evaluated in clinical

studies for Alzheimer's disease (AD). AC Immune will also regain rights to existing GMP drug-product for clinical testing as well

as associated data generated under each of the agreements. AC Immune will carefully review and evaluate available data sets, including

the final open label extension results from the Lauriet trial when they become available and are received in full by AC Immune, before

decisions are made on potential further development and other opportunities.

Andrea Pfeifer, CEO of AC Immune SA, commented: "AC Immune is highly focused on progressing its three active immunotherapies

from its precision medicine pipeline. These product candidates are being developed in ongoing, potentially registrational, Phase 2 clinical

trials, including the recently initiated first prevention study in presymptomatic Alzheimer's disease. This approach, using the

patients' own immune system to slow onset and ultimately prevent neurodegenerative diseases, has the potential to revolutionize

how these conditions are addressed. With the recent milestone payment from our partner in the Tau active immunotherapy program,

plus the USD50 million financing secured in December, we are well financed into 2026, and able to advance multiple high value development

"Regaining the global rights to

crenezumab, semorinemab and the intellectual property surrounding these targets may offer alternative routes to new growth opportunities,

including combination therapies. We are confident that, with full ownership and the learnings from these programs, they could be enhanced

using AC Immune's proprietary next generation technologies. Later this year we will present new data to illustrate

the full potential of these and other monoclonal antibody assets."

Crenezumab is a humanized monoclonal

antibody, an investigational treatment designed to slow AD progression by neutralizing neurotoxic beta-amyloid oligomers. It was designed

by AC Immune to be a conformation-specific monoclonal antibody targeting multiple forms of misfolded Abeta. Crenezumab has an antibody

backbone (IgG4) designed to minimize the inflammatory response in the brain, which may result in a lower incidence of side effects known

as ARIA (Amyloid-Related Imaging Abnormalities). The investigational medicine has demonstrated excellent safety (e.g. no

episodes of ARIA-E in the Phase 3 studies)

and encouraging efficacy signals while undergoing extensive Phase 2 clinical testing. While the Colombian autosomal-dominant AD prevention

trial was not sufficiently powered to show significant cognitive benefits, crenezumab was proven to be safe with numeric trends on the

primary and vast majority of secondary and exploratory endpoints in its favor. The lessons from this study provided useful insights regarding

the desired anti-amyloid immunotherapy profile and designs for prevention trials.

Semorinemab is an investigational monoclonal

anti-Tau antibody that targets the N-terminal portion of the Tau protein, and is designed to bind to Tau and slow its spread between neurons.

Semorinemab has been studied in two Phase 2 studies: Tauriel in early (prodromal-to-mild) AD, where the primary efficacy endpoint was

not met; and Lauriet in mild-to-moderate AD. In Lauriet, a strongly positive and highly statistically significant effect was seen on ADAS-Cog11

(one of two co-primary endpoints) plus statistically significant effects on several key biomarkers, including total Tau and pTau217 in

CSF and plasma. The second co-primary endpoint, ADCS-ADL and the secondary efficacy endpoints did not reach significance. Final open label

extension results from the Lauriet trial will be reviewed when they become available and are received in full by AC Immune.

AC Immune SA is a clinical-stage biopharmaceutical

company and a global leader in precision medicine 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, five of which are currently in Phase 2 clinical trials and one of

which is 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 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.

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Forward looking statements

This 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.