# TOPIK Study: A Study to Report Progressive Multifocal Leukoencephalopathy and Other Serious Opportunistic Infections in Natalizumab Treated Participants

> **NCT05236777** · — · COMPLETED · sponsor: **Biogen** · enrollment: 675 (actual)

## Conditions studied

- Multiple Sclerosis

## Interventions

- **DRUG:** Natalizumab

## Key facts

- **NCT ID:** NCT05236777
- **Lead sponsor:** Biogen
- **Sponsor class:** INDUSTRY
- **Phase:** —
- **Study type:** OBSERVATIONAL
- **Status:** COMPLETED
- **Start date:** 2019-01-01
- **Primary completion:** 2025-04-30
- **Final completion:** 2025-04-30
- **Target enrollment:** 675 (ACTUAL)
- **Last updated:** 2025-05-13

## Collaborators

- [object Object]

## Primary source

ClinicalTrials.gov registry: https://clinicaltrials.gov/study/NCT05236777

## Citation

> US National Library of Medicine, ClinicalTrials.gov registration NCT05236777, "TOPIK Study: A Study to Report Progressive Multifocal Leukoencephalopathy and Other Serious Opportunistic Infections in Natalizumab Treated Participants". Retrieved via AI Analytics 2026-06-25 from https://api.ai-analytics.org/clinical/NCT05236777. Licensed CC0.

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