Elena Ratti

Background: Gosuranemab is a humanized monoclonal antibody binding tau at the N‐terminal domain. The TANGO study is a randomized, placebo‐controlled, global Phase 2 Study evaluating safety and clinical efficacy of gosuranemab in patients diagnosed with mild cognitive impairment (MCI) due to AD or mild AD dementia. We describe baseline characteristics from the TANGO study, the first evaluation of gosuranemab in AD.Method: Randomized, double‐blind, placebo‐controlled, parallel‐group Phase 2 study (TANGO) enrolled globally over 600 individuals aged 50‐80 years, diagnosed with MCI due to AD or mild AD, Clinical Dementia Rating (CDR) global score 0.5‐1, CDR Memory Box score of ≥0.5, Mini‐Mental State Examination (MMSE) score 22‐30, objective evidence of cognitive impairment at Screening and elevated brain amyloid as assessed by PET or cerebrospinal fluid (CSF) levels. Participants were randomized 1:1:2:2 to monthly intravenous low, medium, high dose of gosuranemab or placebo during the 76‐week treatment period. After completion of the placebo‐controlled period, patients may enter a long‐term extension during which all patients receive gosuranemab. The primary endpoints included incidences of adverse events, serious adverse events, abnormalities in safety assessments. The secondary endpoints included change from baseline in CDR‐Sum of Boxes score and incidence of anti‐gosuranemab antibodies in serum. Key exploratory endpoints included change from baseline in MMSE, AD Cooperative Study‐Activities of Daily Living, Functional Activities Questionnaire, AD Assessment Scale‐Cognitive Subscale, tau levels in CSF and/or in brain measured by ¹⁸F‐MK6240 PET and pharmacokinetic parameters.Result: TANGO is now fully enrolled and ongoing; over 600 patients were randomized and have received ≥1 dose of study medication. Approximately half of the patients were enrolled in either the CSF or tau PET sub‐studies. Approximately half of the patients are women (50.5%). The percentage of patients diagnosed with Mild AD at baseline is 53%. MMSE mean (standard deviation [SD]) score at baseline was 25 (2.3).Conclusion: TANGO will assess the safety profile, tolerability and clinical efficacy of gosuranemab in individuals who, per baseline characteristics, are representative of patients with early AD. Study Support: funded by Biogen.

Objectives: To compare quantitative EEG signal and test-retest reliability of medical grade and consumer EEG systems. Methods: Resting state EEG was acquired by two medical grade (B-Alert, Enobio) and two consumer (Muse, Mindwave) EEG systems in 5 healthy subjects during two study visits. EEG patterns, power spectral densities (PSDs) and test/retest reliability in eyes closed and eyes open conditions were compared across the four systems, focusing on Fp1, the only common electrode. Fp1 PSDs were obtained using Welch’s modified periodogram method and averaged for the five subjects for each visit. The test/retest results were calculated as a ratio of Visit 1/Visit 2 Fp1 channel PSD at each one second epoch. Results: B-Alert, Enobio and Mindwave Fp1 power spectra were similar. Muse showed a broadband increase in power spectra and the highest relative variation across test-retest acquisitions. Consumer systems were more prone to artifact due to eye blinks and muscle movement in the frontal region. Conclusions: EEG data can be successfully collected from all four systems tested. Although there was slightly more time required for application, medical systems offer clear advantages in data quality, reliability and depth of analysis over the consumer systems. Significance: This evaluation provides evidence for informed selection of EEG systems appropriate for clinical trials.