AC Immune Announces Interim Phase 1b/2a Data Showing that its ACI-35.030 Anti-pTau Alzheimer's Vaccine Generates a Potent Immune Response Observed strong induction of antibodies specific for pathological fo

AC Immune Announces Interim Phase 1b/2a Data

Showing that its ACI-35.030

Anti-pTau Alzheimer's Vaccine Generates a Potent Immune Response

Observed strong induction of antibodies

specific for pathological forms of Tau with ACI-35.030 treatment

New data presented at 14th

CTAD conference support ACI-35.030's advancement into late-stage development

Lausanne, Switzerland, November 12, 2021

- AC Immune SA (NASDAQ: ACIU), a Swiss-based, clinical-stage biopharmaceutical company with a broad pipeline focused on neurodegenerative

diseases, today presented new interim Phase 1b/2a data on ACI-35.030, a first-in-class anti-phosphorylated-Tau (pTau) vaccine candidate

being developed in partnership with Janssen Pharmaceuticals, Inc., at the 14th Clinical Trials on Alzheimer's Disease (CTAD)

conference, which is being held in Boston, Massachusetts from November 9-12, 2021.

ACI-35.030 is the first AD vaccine candidate designed

to generate antibodies targeting pathological pTau in the brain. At CTAD, AC Immune's Chief Medical Officer Johannes Streffer gave

an on-demand oral presentation featuring data from an ongoing, placebo-controlled

Phase 1b/2a trial evaluating ACI-35.030 in participants with early Alzheimer's disease (AD). Results from the trial show

that ACI-35.030 treatment led to the strong induction of antibodies specific for pathological forms of Tau such as pTau and its aggregated

form, enriched paired helical filaments (ePHF).

Additional key findings from the CTAD presentation

As previously announced, the ongoing Phase 1b/2a study has been expanded

to include a total of 24 AD participants in the mid-dose sub-cohort. This expansion was designed to support the advancement of ACI-35.030

into late-stage development.

Prof. Andrea Pfeifer, CEO of AC Immune SA, commented:

"To see such a strong and lasting immune response against a self-protein in an elderly population is both an exceptional finding

and an important step towards shifting the AD treatment paradigm towards earlier treatment and

prevention. Pathological pTau is present in the

CSF as a precursor many years before Tau accumulation is detectable via imaging techniques. By developing ACI-35.030 while leveraging

cutting edge Tau diagnostics, we aim to deliver on the significant promise this anti-pTau vaccine has shown as a potential early intervention

for AD. We look forward to continuing our collaboration with Janssen Pharmaceuticals, Inc. and to reporting additional immunogenicity

data from the Phase 1b/2a trial's high-dose group."

Prof. Philip Scheltens, Professor of Neurology

at Amsterdam UMC Alzheimer Center and Principal Investigator of the Phase 1b/2a study, commented: " These promising results

provide important preliminary data, and these findings may aid in dose selection for later stage investigation. This information will

be invaluable as we work to further ACI-35.030's clinical development and ultimately fulfill the hopes of clinicians and patients

for a therapy that could delay, or even prevent, the onset of AD."

About the SupraAntigen platform

AC Immune's clinically validated SupraAntigen

platform uses proprietary liposomes to rapidly generate novel vaccines (SupraAntigen -V) for active immunization

as well as best-in-class monoclonal antibodies (SupraAntigen -A) for passive immunization against key neurodegenerative

disease targets. Antibodies generated by the platform are highly specific for the pathological conformations of misfolded proteins and

have shown strong safety. The SupraAntigen platform has successfully generated two vaccines and two antibody candidates

that have been validated in clinical studies and has led to multiple global partnerships with world-leading pharmaceutical companies.

In addition to targeting Amyloid-beta and Tau, AC Immune has generated conformation-specific antibodies against emerging neurodegenerative

disease targets including alpha-synuclein, TDP-43 and the NLRP3 inflammasome pathway.

About the Phase 1b/2a pTau AD Vaccine Trial

The Phase 1b/2a study is a randomized, multicenter,

double-blind, placebo-controlled clinical study with a primary objective to assess the safety, tolerability and immunogenicity of different

dosages of ACI-35.030 and JACI-35.054 in participants with early AD. Secondary objectives will assess additional immunogenicity parameters,

while exploratory endpoints will include notable biomarkers of progression of AD as well as clinical assessments. This Phase 1b/2a study

evaluating ACI-35.030 and JACI-35.054 was initiated in Q3 2019 and is currently ongoing.

AC Immune SA is clinical-stage biopharmaceutical

company that aims to become 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 ten therapeutic and three diagnostic candidates, six of which are currently in clinical trials. AC

Immune has a strong track record of securing strategic partnerships with leading global pharmaceutical companies including Genentech,

a member of the Roche Group, Eli Lilly and Company, and Janssen

Pharmaceuticals, Inc., resulting in substantial

non-dilutive funding to advance its proprietary programs and >$3 billion in potential milestone payments.

SupraAntigen is a registered

trademark of AC Immune SA in the following territories: AU, EU, CH, GB, JP and RU. Morphomer is a registered

trademark of AC Immune SA in CN, CH, GB, JP, and NO.

For further information, please contact:

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