AC Immune & Janssen Pharmaceuticals Report Interim Results for Phase 2 Tau Vaccine Program


AC Immune SA recently announced new interim 10-week data from the high-dose cohort of a placebo-controlled Phase 1b/2a trial evaluating ACI-35.030, a first-in-class phosphorylated-Tau (pTau) vaccine candidate in participants with early Alzheimer’s disease (AD). The company previously reported interim data from low-dose and mid-dose cohorts.

ACI-35.030, based on AC Immune’s SupraAntigen platform, is the first AD vaccine candidate designed to generate antibodies targeting pathological pTau in the brain. New interim data from the Phase 1b/2a trial show that the high-dose of ACI-35.030 led to the strong induction of antibodies selective for pTau and its aggregated form, enriched paired helical filaments (ePHF). These data are consistent with those previously announced for the trial’s mid-dose cohort that showed median anti-pTau antibody titers increasing from baseline by two orders of magnitude at week 2 after a first injection.

Additional key findings from the high-dose interim analysis include:

  • Results indicate that the induced immune response selectively targets pTau, as shown by an increase in the anti-pTau/anti-Tau IgG ratio over time up to week 10.
  • In this interim data set to week 10, median levels of antibodies reactive with pathological Tau (ePHF) were boosted with both the first and second vaccine injections.
  • Safety data provide further support for ACI-35.030’s favorable safety and tolerability profile, as no clinically relevant safety concerns have been observed to date.

Prof. Andrea Pfeifer, CEO of AC Immune SA, said “These latest interim results add to the robust clinical dataset supporting plans for continued late-stage development. The observed antibody response also shows a preference for pathological pTau, which is present in AD years before Tau accumulation can be detected via brain imaging. With these results we believe ACI-35.030 holds significant promise as a first-in-class therapeutic that could shift the AD treatment paradigm towards earlier treatment and prevention, especially when used alongside cutting-edge pTau diagnostics as part of a precision medicine approach. We look forward to the continued development of ACI-35.030.”

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.

The pTau vaccine candidate is being developed in collaboration with Janssen Pharmaceuticals, Inc., part of the Janssen Pharmaceutical Companies of Johnson & Johnson.

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.

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.