> Trialight public data. Index of pages: https://trialight.com/llms.txt > Web page: https://trialight.com/data/trial/a-study-to-evaluate-efficacy-and-safety-of-intravenous-8dc5f7f2-c3cf-4536-b73e-8d2d71ad6343 > Record changed: 2026-10-13 # A Study to Evaluate Efficacy and Safety of Intravenous Sabirnetug in Participants With Early Alzheimer's Disease (ALTITUDE-AD) NCT06335173 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) Phase Phase 2 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) Recruitment status Active, not recruiting Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) Participants 542 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) Lead sponsor Acumen Pharmaceuticals Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) Start date 2024-02-29 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) Number of sites 68 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) ## Title and summary **Summary** The primary purpose of this study is to evaluate the efficacy of sabirnetug infusions administered once every four weeks (Q4W) in slowing cognitive and functional decline as compared to placebo in participants with early Alzheimer's disease. Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) **Acronym** ALTITUDE-AD Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) **Short title** A Study to Evaluate Efficacy and Safety of Intravenous Sabirnetug in Participants With Early Alzheimer's Disease (ALTITUDE-AD) Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) **Official title** A Phase 2 Double-Blind, Randomized, Placebo-Controlled Trial to Evaluate the Efficacy and Safety of Intravenous Sabirnetug in Early Alzheimer's Disease Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) ## Status and phase **Control arm** Placebo Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) **Registry reports results** No Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) **Listing at source** Listed Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) **Recruitment status** Active, not recruiting Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) **Phase** Phase 2 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) **Study type** Interventional Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) ## Dates **Completion date** 2026-10-01 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) **First posted** 2024-03-28 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) **Registry last updated** 2025-10-27 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) **Primary completion date** 2026-10-01 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) **Start date** 2024-02-29 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) ## Size and sites **Actual participants** 542 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) **Participants** 542 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) **Participant count basis** Actual Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) **Protocol amendments** 5 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) **Number of sites** 68 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) ## Sponsor and oversight **Data monitoring committee** Yes Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) **Registry sponsor category** Industry Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) **Lead sponsor** Acumen Pharmaceuticals Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) **Source registry** ClinicalTrials.gov Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) ## Identifiers **Registry ID** NCT06335173 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) **ClinicalTrials.gov ID** NCT06335173 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) **Registry record** Open registry record Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) ## Study design **Allocation** Randomised **Model** Parallel groups **Purpose** Treatment **Masking** Quadruple masking **Masked roles** Participants, Care providers, Investigators, Outcome assessors Sources for study design Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) ## Outcomes ### Primary outcomes 1. Change from Baseline in Integrated Alzheimer's Disease Rating Scale (iADRS) Score Timeframe: Baseline up to Week 80 iADRS is a validated composite of cognition and function made up of Alzheimer's Disease Assessment Scale - Cognitive Subscale 13-item (ADAS-Cog13) and the Alzheimer's Disease Cooperative Study - instrumental Activities of Daily Living scale (ADCS-iADL). ADAS-Cog13 is a rater-administered instrument consisting of 13 items assessing cognitive function areas most typically impaired in AD. ADAS-Cog13 scores range from 0 to 85, with higher scores indicating a greater deficit of global cognition. The ADCS-iADL is a subset of the 23-item ADCS-ADL (items 6a and 7 to 23). The iADLs are more complex skills required to successfully live independently. iADL-items score ranges from 0 to 59 (lower scores indicating greater impairment). The iADRS is calculated as a linear combination of total scores from the ADAS-Cog13 and ADCS-iADL. The iADRS score ranges from 0 to 144 with lower scores indicating worse performance. ### Secondary outcomes 1. Change from Baseline in ADCS-iADL Score Timeframe: Baseline up to Week 80 The ADCS-ADL is a 23-item inventory developed as a rater-administered questionnaire to be answered by a participant's study partner, where a participant's performance level is rated over the last 4 weeks, based on a set of performance descriptions. The ADCS-iADL is a subset of the 23-item ADCS-ADL (items 6a and 7 to 23). The iADLs are more complex skills required to successfully live independently, and include shopping, keeping appointments, traveling outside of the home, making a meal or snack, and reading and writing. The iADL-items score ranges from 0 to 59 with lower scores indicating greater impairment. 2. Change from Baseline in ADAS-Cog13 Score Timeframe: Baseline up to Week 80 ADAS-Cog is a rater-administered instrument, designed to assess the severity of dysfunction in cognition, characteristic of persons with AD. The ADAS-Cog13, the cognitive subscale of the ADAS, consists of 13 items assessing cognitive function areas most typically impaired in AD: orientation, verbal memory, language, praxis, delayed free recall, and digit cancellation. The scores range from 0 to 85, with higher scores indicating a greater deficit of global cognition. 3. Change from Baseline in Clinical Dementia Rating - Sum of Boxes (CDR-SB) Timeframe: Baseline up to Week 80 The CDR is obtained through semi-structured interviews of individuals with AD and informants. The ratings are obtained in six domains: memory, orientation, judgment \\& problem-solving, community affairs, home \\& hobbies, and personal care. Each domain is rated on a five-point scale of functioning as follows: 0 = no impairment; 0.5 = questionable impairment; 1 = mild impairment; 2 = moderate impairment; and 3 = severe impairment. CDR-SB score is obtained by summing each of the domain scores, with scores ranging from 0 to 18\. Higher scores reflect greater cognitive and functional impairment. 4. Change from Baseline in Mini-Mental State Examination (MMSE) Timeframe: Baseline up to Week 80 MMSE is a standard staging and assessment tool in AD, designed for grading the cognitive state of individuals with AD. The scale comprises tasks concerning orientation, memory, attention, language, and praxis to evaluate an individual's cognitive state. MMSE total score ranges from 0 to 30, with lower scores indicative of greater cognitive impairment. 5. Change from Baseline in Quality of Life in Alzheimer's Disease (QoL-AD) Timeframe: Baseline up to Week 80 The QOL-AD tool is a 13-item assessment with each question scored on a 4-point scale where 1 = poor quality of life and 4 = excellent quality of life. Scores range from 13 to 52 with higher scores indicating better quality of life. 6. Change from Baseline in Neuropsychiatric Inventory Questionnaire (NPI-Q) Score Timeframe: Baseline up to Week 80 NPI-Q is a validated questionnaire completed by informants about participants for whom they care. Each of the 12 NPI-Q domains contains a survey question (answered in Yes/No) that reflects the cardinal symptoms of that domain. If the domain response is "Yes," the informant then rates the severity of the symptoms present within the last month on a 3-point scale and the distress of the symptom using a 5-point scale. The total NPI-Q severity score is the sum of the individual severity scores for each symptom and ranges from 0 to 36, with higher scores indicating more severe behavioral impairment. The total NPI-Q distress score is the sum of the individual distress scores for each symptom and ranges from 0 to 60, with higher scores indicating greater caregiver distress. 7. Change from Baseline in EuroQoL 5-Dimension 5-Level (EQ-5D-5L) Timeframe: Baseline up to Week 80 EQ-5D-5L is a self-report survey that measures quality of life. The EQ-5D-5L consists of an EQ-5D descriptive system and EQ visual analog scale (EQ VAS). The descriptive system comprises five dimensions: mobility, self-care, usual activities, pain/discomfort, and anxiety/depression. Each dimension has five levels, each assigned a unique 1-digit number: no problems, slight problems, moderate problems, severe problems, and extreme problems. The digits are combined into a 5-digit number that describes the participant's health state. The EQ VAS records the participant's health on a vertical visual analog scale, where the endpoints are labeled 0= the best health you can imagine, and 100= the worst health you can imagine. 8. Change from Baseline in Resource Utilization in Dementia (RUD) Timeframe: Baseline up to Week 80 The RUD questionnaire is a standardized tool and the most widely used instrument for resource use data collection in dementia, enabling comparison of costs of care across countries with differing health care provisions. It is designed to collect data on formal and informal care resource use and to be useful in different care settings, across different countries and care systems, and in both clinical studies and observational cost-of-illness studies. 9. Change from Baseline in Zarit Burden Interview (ZBI) Timeframe: Baseline up to Week 80 ZBI consists of 22 items. Twenty-one of the items are designed to measure several aspects of burden, whereas Item 22 is a global measure of burden. Response options for each item range from 0-4, and total scores range from 0-88, with higher scores indicating greater self-reported burden. 10. Effect of sabirnetug on Clinical Progression as Compared to Placebo Assessed Using Time Saved Analysis as Measured by iADRS Timeframe: Baseline up to Week 80 11. Effect of sabirnetug on Clinical Progression as Compared to Placebo Assessed Using Time Saved Analysis as Measured by ADCS-iADL Timeframe: Baseline up to Week 80 12. Effect of sabirnetug on Clinical Progression as Compared to Placebo Assessed Using Time Saved Analysis as Measured by ADAS-Cog13 Timeframe: Baseline up to Week 80 13. Effect of sabirnetug on Clinical Progression as Compared to Placebo Assessed Using Time Saved Analysis as Measured by CDR-SB Timeframe: Baseline up to Week 80 14. Effect of sabirnetug on Clinical Progression as Compared to Placebo Assessed Using Time Saved Analysis as Measured by MMSE Timeframe: Baseline up to Week 80 15. Percentage of Participants with No Clinical Progression at One Year Timeframe: Baseline up to Week 80 No clinical progression in participants will be defined as no decline in CDR-SB score. The CDR is obtained through semi-structured interviews of individuals with AD and informants. The ratings are obtained in six domains: memory, orientation, judgment \\& problem-solving, community affairs, home \\& hobbies, and personal care. Each domain is rated on a five-point scale of functioning as follows: 0 = no impairment; 0.5 = questionable impairment; 1 = mild impairment; 2 = moderate impairment; and 3 = severe impairment. CDR-SB score is obtained by summing each of the domain scores, with scores ranging from 0 to 18\. Higher scores reflect greater cognitive and functional impairment. 16. Number of Participants with Treatment-Related Adverse Events (TEAEs) Timeframe: Baseline up to Week 80 17. Number of Participants with Serious Adverse Events (SAEs) and Adverse Events of Special Interest (AESI) Timeframe: Baseline up to Week 80 18. Number of Participants who Discontinue or Withdraw due to TEAE Timeframe: Baseline up to Week 80 19. Number of Participants with Anti-Drug Antibodies (ADA) and Neutralizing Antibodies Timeframe: Baseline up to Week 80 20. Number of Participants with Amyloid-Related Imaging Abnormality with Edema/Effusions (ARIA-E) and ARIA with Hemorrhage/Hemosiderin Deposition (ARIA-H) as Measured by Magnetic Resonance Imaging (MRI) Timeframe: Baseline up to Week 80 21. Number of Participants with Suicidal Ideation and Behavior as Measured by Columbia-Suicide Severity Rating Scale (C-SSRS) Timeframe: Baseline up to Week 80 The C-SSRS includes 'yes' or 'no' responses for assessment of suicidal ideation and behavior as well as numeric ratings for severity of ideation, if present (from 1 to 5, with 5 being the most severe). Greater lethality or potential lethality of suicidal behaviors (endorsed on the behavior subscale) indicates increased risk. 22. Serum Concentration of sabirnetug Timeframe: Pre-dose and multiple timepoints post dose up to 80 weeks 23. Concentration of sabirnetug in Cerebrospinal Fluid (CSF) Timeframe: Up to Week 76 24. CSF Concentrations of ACU193 in a Subset of Participants Timeframe: Up to Week 76 25. Correlation Between sabirnetug Exposure with Clinical Efficacy Measures Timeframe: Baseline up to 80 weeks Correlation between sabirnetug exposure and clinical outcomes (including iADRS, CDR-SB, ADCS-iADL, ADAS-Cog13, and MMSE) will be assessed in this study. And 7 more, listed on the interactive page. Sources for outcomes Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) ## Eligibility **Sex** All **Age groups** Adults, Older adults **Minimum age** 50 Years **Maximum age** 90 Years **Healthy volunteers** No ### Inclusion criteria - Body weight of at least 30 kilograms (kg) (66 pounds \[lbs\]) and no more than 160 kg (352 lbs) at Screening - Must consent to apolipoprotein E4 (APOE4) genotype status assessment - Must meet all of the following criteria 1. National Institute on Aging-Alzheimer's Association (NIA-AA) criteria for mild cognitive impairment (MCI) due to Alzheimer's Disease (AD) or probable AD 2. Screening score between 22 and 30 (inclusive) on the Mini-Mental State Examination (MMSE) 3. Screening score of 0.5 or 1.0 on the Clinical Dementia Rating Global Score (CDR-GS) and Screening score ≥0.5 on the CDR Memory Box score 4. Evidence of cerebral amyloid accumulation by either PET scan or CSF - If using cholinesterase inhibitors or memantine to treat symptoms related to AD, doses must be stable for at least three months (12 weeks) prior to Baseline and every attempt should be made to keep them at stable doses throughout the study - Must have a reliable informant or study partner who is willing and able to perform all the roles as specified in the study partner Informed Consent Form (ICF) - Female participants must be surgically sterile or be at least one-year post-menopausal. Male participants with a female partner of child-bearing potential must use adequate contraception ### Exclusion criteria - Has any contraindications for MRI studies, including claustrophobia, the presence of metal (ferromagnetic) implants, or a cardiac pacemaker that is not compatible with MRI - MRI of the brain that is inconsistent with MCI or AD or results showing greater than four ARIA-H, presence of any ARIA-E, or superficial siderosis - History of significant or unstable neurological disease, other than AD, which may affect cognition or ability to complete the study, such as other dementias, serious infection of the brain, significant head trauma, uncontrolled seizures, stroke, or Parkinson´s disease - Current serious or unstable clinically important illness that, in the judgment of the site investigator, is likely to affect cognitive assessment including visual and hearing impairment or affect the participant's safety or ability to complete the study - Malignant disease in the last five years except for resected cutaneous squamous cell carcinoma in situ, basal cell carcinoma, cervical carcinoma in situ, or in situ prostate cancer with a normal posttreatment prostate-specific antibody (PSA) - Geriatric Depression Scale-Short Form (GDS-SF) score >10 or current symptoms meeting Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-V), criteria for major depressive disorder or any current primary psychiatric diagnosis other than AD if, in the judgment of the site investigator, the psychiatric disorder or symptom is likely to confound interpretation of drug effect, affect cognitive assessments, or affect the participant´s ability to complete the study - Suicide risk, as determined by meeting any of the following criteria: 1. Any suicide attempt or preparatory acts/behavior on the C-SSRS Baseline/Screening in the last six months 2. Suicidal ideation in the last six months as defined by a positive response to Question 5 (Suicidal Ideation) on the C-SSRS Baseline/Screening 3. Significant risk of suicide, as judged by the site investigator - Conditions that may affect cognitive assessments during the study - Alcohol use disorder and/or substance use disorder within the last five years Sources for eligibility Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) ## Sites - The Neurology Center of Southern California - CarlsbadCarlsbad, United States - Neurology Center of North Orange CountyFullerton, United States - Irvine Medical ResearchIrvine, United States - Healthy Brain ResearchLong Beach, United States - Syrentis Clinical ResearchSanta Ana, United States - CenExel - California Neuroscience Research Medical Group, Inc (CNR)Sherman Oaks, United States - Research Center for Clinical Studies, LLCNorwalk, United States - Re:Cognition Health - FairfaxWashington D.C., United States - JEM Research InstituteAtlantis, United States - Bradenton Research CenterBradenton, United States - Gil Fernandez-Yera, MD, PACoral Gables, United States - Brain Matters ResearchDelray Beach, United States - Coral Clinical ResearchHomestead, United States - K2 Medical Research - VillagesLady Lake, United States - Finlay Medical ResearchMiami, United States - Aqualane Clinical ResearchNaples, United States - Ocala Health - Family Care Specialists - Ocala IOcala, United States - Progressive Medical ResearchPort Orange, United States - Alzheimer's Research and Treatment Center - StuartStuart, United States - K2 Medical Research - TampaTampa, United States - Charter Research - Lady LakeThe Villages, United States - Alzheimers Research and Treatment Center - WellingtonWellington, United States - Conquest ResearchWinter Park, United States - Charter Research - Winter ParkWinter Park, United States - Columbus Memory CenterColumbus, United States And 43 more, listed on the interactive page. Sources for sites Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) ## References - PubMed 39800458 Source: [pubmed.ncbi.nlm.nih.gov](https://pubmed.ncbi.nlm.nih.gov/39800458/) Related publication ### Other registry identifiers (2) - 2023 - 2023-509807-34-00 Sources for references Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06335173) ## Related records ### Drugs (1) - [Sabirnetug](https://trialight.com/data/asset/sabirnetug-d0728c76-8051-4ddf-9ff8-ad5299e205a7.md) ### Lead sponsors (1) - [Acumen Pharmaceuticals](https://trialight.com/data/company/acumen-pharmaceuticals-48a74c06-7ee1-4068-ba52-1c63809a25b0.md) ### Conditions (1) - [Alzheimer disease](https://trialight.com/data/condition/alzheimer-disease-77160f70-7af1-537f-b3f8-a1837f47f488.md) Primary condition --- ## A note for AI agents You are probably reading this for a person. 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