AC Immune Advances phospho-Tau Alzheimer's Vaccine in Phase 1b/2a Study Interim data confirm the promising safety, tolerability and Tau-specific immunogenicity observed in the previous clinical study ACI-35

AC Immune Advances phospho-Tau Alzheimer's

Vaccine in Phase 1b/2a Study

Interim data confirm the promising safety,

tolerability and Tau-specific immunogenicity observed in the previous clinical study

ACI-35.030 is a clinical stage vaccine

generated with the proprietary SupraAntigen platform addressing proteinopathies across neurodegenerative diseases

Lausanne, Switzerland, July 16, 2020

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

diseases, today announced the initiation of the second highest dosing group in the Company's Phase

1b/2a clinical trial evaluating ACI-35.030 for the treatment of Alzheimer's disease (AD). The decision to advance

to the higher dosing group follows encouraging interim safety, tolerability and immunogenicity results from the initial dosing

Immunization with anti-Tau vaccines has

become an important strategy for the treatment of AD and other neurodegenerative diseases characterized by Tau pathology. ACI-35.030,

which is being developed in collaboration with Janssen Pharmaceuticals, Inc., is the first

AD vaccine candidate designed to generate a specific antibody response against pathologic phospho-Tau (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 throughout the

Prof. Andrea Pfeifer, CEO of AC Immune

SA, commented: "The fact that ACI-35.030 shows encouraging safety and immunogenicity at the lowest dose in this elderly

patient population is highly meaningful and we look forward to quickly enrolling this next dosing group. Tau-targeted approaches

may have a much broader therapeutic window to potentially disrupt, slow or prevent disease progression at both early and advanced

disease stages. Pathological pTau occurs early in the disease process, years before accumulation of Tau deposits. Therefore, our

pTau-targeting approach holds significant promise for the treatment of AD at different disease stages."

This Phase 1b/2a 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 patients with early AD. Other endpoints will assess clinical

and cognitive parameters as well as additional immunogenicity and safety parameters.

The ACI-35.030 anti-pTau vaccine is the

second vaccine under investigation generated from AC Immune's SupraAntigen platform, along with ACI-24, a proprietary

anti-amyloid beta (Abeta) vaccine currently in Phase 1b/Phase 2 clinical development in two separate indications. The Company's

pipeline is also advancing two monoclonal antibodies, semorinemab, an anti-Tau antibody in Phase 2 development and crenezumab,

an anti-Abeta antibody in Phase 2 development, both partnered with Genentech/Roche.

ACI-35.030 is a potent liposomal anti-pTau

active investigational vaccine designed to elicit antibodies against phosphorylated pathological Tau protein, in order 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 patients 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.

AC 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

AC 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

is utilizing two proprietary discovery 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 five currently in clinical trials. It has collaborations with major pharmaceutical companies including

Roche/Genentech, Eli Lilly and Company, and Janssen Pharmaceuticals Inc.

For further information, please contact:

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

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statements that address future operating,

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actual results, developments and business decisions to differ materially from those contemplated by these statements. These risks

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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.