Recent Updates
Recently added Catalysts

Diranersen

Phase 2

Mild Cognitive Impairment Due to Alzheimer's Disease | Small molecule | Neurology |Biogen Inc.|Last Updated: Jul 10, 2026

Success Probability

Subscribe to view

Market & Valuation

Subscribe to view

Trial Design

RandomizedDouble-BlindPLACEBO_CONTROLLEDDMC
Total Trials1
Total Enrollment416

FDA Designations

FAST_TRACK

Clinical trial landscape

Diranersen · 2 trials · 3 indications

Phase 2 1Phase 1 1
NCT05399888A Study to Learn About the Safety of Diranersen (BIIB080) Injections and Whether They Can Improve Symptoms of Participants With Mild Cognitive Impairment Due to Alzheimer's Disease (AD) or Mild AD Dementia Between 50 to 80 Years of AgeMild Cognitive Impairment Due to Alzheimer's Disease
ACTIVE NOT_RECRUITING416 Analytics
PHASE2ACTIVE NOT_RECRUITING
A Study to Learn About the Safety of Diranersen (BIIB080) Injections and Whether They Can Improve Symptoms of Participants With Mild Cognitive Impairment Due to Alzheimer's Disease (AD) or Mild AD Dementia Between 50 to 80 Years of Age
Mild Cognitive Impairment Due to Alzheimer's DiseaseUnlock trial analytics

Study Endpoints

Primary Endpoints

Dose response in Change From Baseline to Week 76 on the CDR-SB
Baseline to Week 76

The Clinical Dementia Rating (CDR) scale is a clinician-rated dementia staging system that tracks the progression of cognitive impairment in 6 categories (memory, orientation, judgment and problem solving, community affairs, home and hobbies, and personal care). Each category is scored on a 5-point scale in which None=0, Questionable=0.5, Mild=1, Moderate=2, and Severe=3. The global CDR score is established by clinical scoring rules and has values of 0 (no dementia), 0.5, (questionable dementia), 1 (mild dementia), 2 (moderate dementia), and 3 (severe dementia). The CDR-SB is obtained by adding the ratings in each of the 6 categories and ranges from 0 to 18 with higher scores indicative of greater impairment.

CNS Biodistribution of [89Zr]Zr-DFO-Diranersen Assessed as the Percentage of Dose Taken up by Each Region of Interest (ROI)
Post-dose on Days 1, 2, 5, and 8

CNS biodistribution of \[89Zr\]Zr-DFO-Diranersen will be measured using the Positron Emission tomography (PET) imaging. The mean radioactive counts per voxel will be measured. These counts will be converted to the percentage of dose that is taken up by each ROI (% of injected tracer dose per gram of tissue) to quantify the biodistribution in measurable tissues and CSF spaces at relative distances from the lumbar injection using quantitative scaling algorithms.

Secondary Endpoints

Change From Baseline to Week 76 on the CDR-SB
Baseline to Week 76
Change From Baseline to Week 76 on the Alzheimer's Disease Cooperative Study Activities of Daily Living for Mild Cognitive Impairment (ADCS-ADL-MCI)
Baseline to Week 76
Change From Baseline to Week 76 on the Alzheimer's Disease Assessment Scale Cognitive Subscale (ADAS-Cog 13)
Baseline to Week 76
Unlock Study Endpoints

Study Design & Arms

AllocationRANDOMIZED
MaskingQUADRUPLE
ModelPARALLEL
PurposeTREATMENT

Treatment Arms

ArmTypeDescription
Placebo Q12WPLACEBO_COMPARATORParticipants will receive diranersen-matching placebo, intrathecal (IT) injection, once on Day 1 and then once every 12 weeks (Q12W) for up to 72 weeks, during the placebo-controlled period. Eligible participants will enter the LTE period, during which they will be randomized to receive diranersen high dose, IT injection, either Q12W or once every 24 weeks (Q24W) for an additional 96 weeks.
Diranersen Low Dose Q24WEXPERIMENTALParticipants will receive a low dose of diranersen, IT injection, Q24W from Week 1 up to 72 weeks and diranersen-matching placebo, IT injection, once at Weeks 12, 36, and 60 during the placebo-controlled period. Eligible participants will enter the LTE period, during which they will continue to receive diranersen low dose, IT injection, Q24W for an additional 96 weeks.
Diranersen High Dose Q24WEXPERIMENTALParticipants will receive a high dose of diranersen, IT injection, Q24W from Week 1 up to 72 weeks and diranersen-matching placebo, IT injection, once at Weeks 12, 36, and 60 during the placebo-controlled period. Eligible participants will enter the LTE period, during which they will continue to receive diranersen high dose, IT injection, Q24W for an additional 96 weeks.
Diranersen High Dose Q12WEXPERIMENTALParticipants will receive a high dose of diranersen, IT injection, once on Day 1 and then Q12W for up to 72 weeks during the placebo-controlled period. Eligible participants will enter the LTE period, during which they will continue to receive diranersen high dose, IT injection, Q12W for an additional 96 weeks.
[89Zr]Zr-DFO-Diranersen+ DiranersenEXPERIMENTALParticipants will receive a single injection of a small dose of radiolabeled diranersen \[89Zr\]Zr-DFO-diranersen) along with a dose of diranersen together via an intrathecal (IT) injection.

Interventions

NameTypeDescription
DiranersenDRUGAdministered as specified in the treatment arm.
Diranersen-matching placeboDRUGAdministered as specified in the treatment arm.
[89Zr]Zr-DFO-DiranersenDRUGAdministered as specified in the treatment arm.
Unlock Study Design Details

Eligibility Criteria

Age Range50 Years to 80 Years
SexALL
Healthy VolunteersNo
Study Sites138

Key Inclusion Criteria for Placebo-controlled Period: * Must meet all the clinical staging criteria for MCI due to AD (Stage 3) or mild AD dementia (Stage 4) according to the National Institute on Aging at National Institutes of Health and the Alzheimer's Association (NIA-AA) and must have the foll...

Countries:United StatesAustraliaBelgiumCanadaCzechiaDenmarkFinlandFranceGermanyItalyJapanNetherlandsPolandSpainSwedenSwitzerlandUnited Kingdom
Unlock Eligibility Criteria

Recent Changes (Last 90 Days)

MEDIUMAug 10, 2026NCT06454721TRIAL_REMOVED: changed
MEDIUMAug 10, 2026NCT06454721TRIAL_REMOVED: changed
MEDIUMJun 30, 2026NCT05399888lastUpdatePostDate: changed
MEDIUMJun 30, 2026NCT05399888lastUpdatePostDate: changed
MEDIUMJun 30, 2026NCT05399888lastUpdatePostDate: changed

Frequently asked questions about Diranersen

What is Diranersen used for?

Diranersen is an investigational antisense oligonucleotide being studied for mild cognitive impairment due to Alzheimer's disease and mild Alzheimer's disease dementia. It is also being evaluated in healthy volunteers for biodistribution and safety studies. The drug is in clinical development and has not been approved by the FDA.

What does Diranersen target?

Diranersen is an antisense oligonucleotide (ASO), a class of drugs that work by targeting messenger RNA to modulate protein production. Its specific molecular target has not been disclosed in available information. The drug is being investigated for its potential effects on Alzheimer's disease pathology.

Who makes Diranersen?

Diranersen is being developed by Biogen Inc., a biotechnology company traded on the NASDAQ under the ticker symbol BIIB. Biogen is conducting clinical trials to evaluate the safety and efficacy of Diranersen for Alzheimer's disease and related conditions.

What phase is Diranersen in?

Diranersen is in Phase 1 clinical development. One Phase 1 study has been completed, and a Phase 2 study is active but not recruiting participants. The drug is investigational and has not received FDA approval for any indication.

What clinical trials is Diranersen in?

Diranersen is being studied in two clinical trials. NCT05399888 is a Phase 2 study in patients with mild cognitive impairment due to Alzheimer's disease or mild Alzheimer's dementia, with 416 participants across multiple countries. NCT06454721 is a completed Phase 1 microdose study in healthy adults.

Is Diranersen the same as BIIB080?

Yes, Diranersen is also known as BIIB080. Clinical trial records refer to the drug as Diranersen (BIIB080), confirming that these names identify the same investigational compound being developed by Biogen for Alzheimer's disease.