# A Study to Assess the Safety, Tolerability, and Effect on Disease Progression of BIIB105 in Participants With Amyotrophic Lateral Sclerosis (ALS) and Participants With the ALS Ataxin-2 (ATXN2) Genetic Mutation

> **NCT04494256** · PHASE1,PHASE2 · TERMINATED · sponsor: **Biogen** · enrollment: 99 (actual)

## Conditions studied

- Amyotrophic Lateral Sclerosis

## Interventions

- **DRUG:** BIIB105
- **DRUG:** Placebo

## Key facts

- **NCT ID:** NCT04494256
- **Lead sponsor:** Biogen
- **Sponsor class:** INDUSTRY
- **Phase:** PHASE1,PHASE2
- **Study type:** INTERVENTIONAL
- **Status:** TERMINATED
- **Start date:** 2020-09-28
- **Primary completion:** 2024-08-13
- **Final completion:** 2024-08-13
- **Target enrollment:** 99 (ACTUAL)
- **Why stopped:** Sponsor's decision
- **Last updated:** 2025-10-09


## Primary source

ClinicalTrials.gov registry: https://clinicaltrials.gov/study/NCT04494256

## Citation

> US National Library of Medicine, ClinicalTrials.gov registration NCT04494256, "A Study to Assess the Safety, Tolerability, and Effect on Disease Progression of BIIB105 in Participants With Amyotrophic Lateral Sclerosis (ALS) and Participants With the ALS Ataxin-2 (ATXN2) Genetic Mutation". Retrieved via AI Analytics 2026-05-26 from https://api.ai-analytics.org/clinical/NCT04494256. Licensed CC0.

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