AC Immune's Alzheimer's Vaccine Generates Potent Anti-pTau Antibody Response in a Phase 1b/2a Study Interim results of ACI-35.030 vaccination show high titers of antigen-specific antibodies at potentially t

AC Immune's Alzheimer's Vaccine

Generates Potent Anti-pTau Antibody Response in a Phase 1b/2a Study

Interim results of ACI-35.030 vaccination

show high titers of antigen-specific antibodies at potentially therapeutic levels in 100% of older patients with early Alzheimer's

ACI-35.030 was safe and well tolerated

with no safety concerns observed. Results support plans to further develop the Alzheimer's vaccine into Phase 2/3

Lausanne, Switzerland, February 11, 2021

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

diseases, today announced positive interim results from its ongoing Phase 1b/2a clinical trial evaluating its first-in-class anti-phospho-Tau

(pTau) vaccine candidate ACI-35.030 for the treatment of Alzheimer's disease (AD). ACI-35.030 vaccination generated a potent

antigen-specific antibody response against pTau in 100% of older patients with early AD, achieving antibody levels several orders

of magnitude higher than pre-vaccination levels. No clinically relevant adverse events were observed. AC Immune and strategic partner

Janssen Pharmaceuticals, Inc., believe these interim findings from the first two dosing groups support plans to advance the development

of ACI-35.030 for the treatment of AD.

anti-Tau vaccines represents a novel strategy for the treatment of AD and other neurodegenerative diseases characterized by Tau

pathology. ACI-35.030 is a first-in-class vaccine candidate designed to generate a specific antibody response against pTau proteins

in the brain. Anti-pTau antibodies generated by ACI-35.030 have the potential to reduce the spread and seeding of Tau pathology,

which is a major hallmark of AD.

provide encouraging clinical support for ACI-35.030, which employs a new vaccine formulation to achieve active immunization that

significantly improves antibody responses in older patients with potentially attenuated immune systems. Notably, anti-pTau vaccination

generates antibody responses with pharmacokinetic characteristics and target epitopes that differ substantially from the Company's

anti-Tau monoclonal antibody semorinemab, highlighting the comprehensive and complementary nature of AC Immune's anti-Tau

Pfeifer, CEO of AC Immune SA, commented: "These remarkable data show that ACI-35.030 is capable of generating unprecedented

antibody responses against pTau in an elderly population, with very high antigen-specific titers. Importantly, it generated a much

stronger antibody response compared to direct injection of exogenous antibodies. As pathological pTau is present as a precursor

many years before Tau accumulation in the brain is detectable via brain imaging, such results highlight the significant promise

of ACI-35.030 as an early intervention for AD, especially when combined with cutting-edge pTau diagnostics that would enable identification

of people at risk of developing Tau-driven disease. We look forward to continuing to advance ACI-35.030 in our collaboration with

Janssen Pharmaceuticals, Inc., as we aim to bring this potentially breakthrough vaccine to patients."

the Phase 1b/2a study showed:

The companies plan to advance to the third

and highest dosing group, per the study protocol.

ACI-35.030 is derived

from AC Immune's proprietary SupraAntigenTM platform, which accelerates the discovery and development of conformation

specific antibodies and vaccine candidates to power successful therapeutic and diagnostic approaches. Additional clinical-stage

candidates derived from this platform include ACI-24, a proprietary anti-amyloid beta (Abeta) vaccine, crenezumab, an anti-Abeta

monoclonal antibody, and semorinemab, an anti-Tau monoclonal antibody, which is in Phase 2 development for the treatment of moderate

SupraAntigenTM platform has also more recently generated conformation-specific antibodies against emerging neurodegenerative

disease targets such as alpha-synuclein, TDP-43 and the NLRP3 inflammasome pathway. AC Immune's programs directed against

these emerging targets are among the most advanced and comprehensive in the field.

About the Phase 1b/2a pTau AD Vaccine

AC Immune's Phase 1b/2a pTau

AD vaccine trial is a randomized, multicenter, double-blind, placebo-controlled clinical study with a primary objective to assess

the safety, tolerability and immunogenicity of different doses of ACI-35.030 over a 48-week treatment phase in 32 patients with

early AD. Other endpoints will assess clinical and cognitive parameters as well as additional immunogenicity and safety parameters.

ACI-35.030 is a potent liposomal anti-pTau

active investigational vaccine designed to elicit antibodies against phosphorylated pathological Tau protein. It is designed to

reduce and facilitate the clearance of related Tau aggregates, slowing the progression of Tau-pathology and/or treating the underlying

It builds on the success of AC Immune's

ACI-35 vaccine, which demonstrated an early target-specific antibody response against pTau after the first injection in the vast

majority of participants in a Phase 1b study in mild-to-moderate AD. In preclinical studies, ACI-35.030 retained the excellent

non-clinical safety profile and the highly specific antibody response against phosphorylated pathological Tau produced by ACI-35,

while demonstrating an enhanced and more homogeneous antibody response.

Immune is developing the ACI-35.030 vaccine in collaboration with Janssen Pharmaceuticals, Inc., under a 2014 licensing agreement

to develop and commercialize therapeutic anti-Tau vaccines for the treatment of AD and potentially other Tauopathies.

Immune SA is a Nasdaq-listed clinical-stage biopharmaceutical company, which aims to become a global leader in precision medicine

for neurodegenerative diseases. The Company utilizes two proprietary platforms, SupraAntigenTM and MorphomerTM,

to design, discover and develop small molecule and biological therapeutics as well as diagnostic products intended to diagnose,

prevent and modify neurodegenerative diseases caused by misfolding proteins. The Company's pipeline features nine therapeutic and

three diagnostic product candidates, with six currently in clinical trials. It has collaborations with major pharmaceutical companies

including Genentech, a member of the Roche Group, Eli Lilly and Company and Janssen Pharmaceuticals.

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Forward looking statements

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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. These include: the impact of Covid-19

on our business, suppliers, patients and employees and any other impact of Covid-19. 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.