New Data Supporting Crenezumab as Potential Alzheimer's Therapy
AC Immune Partner Life Molecular Imaging Presents New Clinical Study Results for Tau PET-Tracer 18F-PI-2620
AC Immune SA (NASDAQ: ACIU), a Swiss-based, clinical-stage biopharmaceutical company focused on neurodegenerative diseases, today announced the presentation of in vitro data that underscores the clinical rationale for crenezumab, an anti-beta amyloid antibody, as a potential treatment for Alzheimer's disease (AD) - see Ref. 1. Furthermore, the results of a study on PET eligibility supported the use of either amyloid PET or the Elecsys® ß-Amyloid (1-42) CSF immunoassay as eligibility criteria in the CREAD Phase 3 studies of crenezumab in patients with prodromal-to mild AD - see Ref. 2 . These results were presented at the 11th Clinical Trials on Alzheimer's disease Conference (CTAD) that occurred October 24-27th in Barcelona, Spain.
Prof. Andrea Pfeifer, CEO of AC Immune, commented: "The results of these studies support the clinical rationale for crenezumab and further underscore our confidence in the potential of crenezumab to become a transformative therapeutic for Alzheimer's disease."
About the in vitro studies
The two key human brain pathological hallmarks of AD are beta-amyloid plaques and tau fibrillary tangles. Researchers from Genentech, a member of the Roche Group, generated a human-induced pluripotent stem cell (iPSC) neuronal model, which recapitulated AD pathologies and then demonstrated the ability of crenezumab to protect human neurons in vitro from beta-amyloid toxicity. The studies showed that crenezumab protected neurons from effects such as synaptic loss, tau phosphorylation, and neuronal death in a concentration-dependent manner. Further information on these studies is available at CTAD website.
Study on PET eligibility in CREAD Phase III
At the CTAD conference, the results of a study that assessed the concordance of CSF Aß (1-42) and amyloid PET eligibility criteria in a sub-study of the Phase 3 study BN29552 (CREAD) of crenezumab in patients with prodromal-to-mild AD also have been presented. The results showed excellent concordance between CSF Aß (1-42) and amyloid PET. These results supported the use of either amyloid PET or the Elecsys® ß-Amyloid (1-42) CSF immunoassay as eligibility criteria in the CREAD 1 and CREAD 2 Phase 3 studies of crenezumab in patients with prodromal-to mild AD. Further information on these studies is available at CTAD website.
1 Poster P104: The effect of crenezumab on beta-amyloid toxicity-induced synapse loss, neurofibrillary tangles and cell death in human neurons in vitro; Maureen Beresini et al
2 Oral presentation OC33: Concordance of florbetapir (18F) PET and Elecsys® ß-Amyloid(1-42) CSF immunoassay in the CREAD (BN29552) study of crenezumab in prodromal-to-mild AD; Tobias Bittner et al
AC Immune's partner Life Molecular Imaging (LMI, formerly Piramal Imaging) has presented new clinical study results for 18F-PI-2620, a novel tau PET-tracer, allowing further extension of tau PET investigations with this compound in therapeutic clinical trials - see Ref. 1. These results were presented at the 11th Clinical Trials on Alzheimer's disease Conference (CTAD) that occurred October 24-27th in Barcelona, Spain.
Intracellular tau deposition is a key pathologic feature of Alzheimer's disease (AD) and other neurodegenerative disorders. The results of the Test-Retest study for 18F-PI-2620 in AD and non-demented controls (NDC) demonstrated favorable kinetics, high target specificity with low off-target binding and high signal in regions of expected tau pathology.
Prof. Andrea Pfeifer, CEO of AC Immune, commented: "Developing diagnostics to identify patients at early disease stages is considered as one of the most pressing needs in the treatment of Alzheimer's and other neurodegenerative diseases. These encouraging results advance our ability to image tau deposition in the brain, which will enable early and reliable diagnosis of Alzheimer's disease, and guide clinical trials for disease modifying therapeutics."
Dr. Andrew Stephens, Chief Medical Officer at LMI, said: "The excellent Test-Retest data provide excellent quantification accuracy and effect size. The low Test-Retest variability will allow for precise quantification of 18F-PI-2620 uptake in target brain areas in order to detect also subtle changes of Tau deposition over time and during therapeutic interventions in longitudinal studies."
LMI continues to expand its global supply network of 18F-labeled tau PET imaging agent 18F-PI-2620 including several sites in the US, as announced by LMI and its US manufacturing partner SOFIE Inc. earlier this year. Both companies have leveraged their joint resources for broader clinical trial supply availability in the US.
About tau-PET tracers
A brain positron emission tomography (PET) scan is a non-invasive imaging test of the brain involving an imaging device and an imaging agent called a PET tracer. No tau-PET tracers have received regulatory approval for commercial distribution, which represents a huge medical need, not only in Alzheimer's disease but also in other potential tauopathies. Once the tau-PET tracer is introduced to the body, it travels to the brain and binds to abnormal tau protein structures (tau tangles), one of the pathological hallmarks of AD. The imaging device detects the bound tau imaging agent and creates pictures reflecting the amount and distribution of pathological tau in the brain.
1 Poster P118: Clinical validation of 18F-PI-2620 for quantification of tau in subjects with Alzheimer's disease; Ludger Dinkelborg et al