# A Study of TAK-503 in Children and Teenagers With Attention Deficit Hyperactivity Disorder (ADHD)

> **NCT04085172** · PHASE4 · COMPLETED · sponsor: **Shire** · enrollment: 396 (actual)

## Conditions studied

- Attention Deficit Hyperactivity Disorder

## Interventions

- **DRUG:** Guanfacine hydrochloride (TAK-503)
- **DRUG:** Atomoxetine hydrochloride
- **OTHER:** Placebo

## Key facts

- **NCT ID:** NCT04085172
- **Lead sponsor:** Shire
- **Sponsor class:** INDUSTRY
- **Phase:** PHASE4
- **Study type:** INTERVENTIONAL
- **Status:** COMPLETED
- **Start date:** 2019-09-18
- **Primary completion:** 2025-09-02
- **Final completion:** 2025-09-02
- **Target enrollment:** 396 (ACTUAL)
- **Last updated:** 2026-04-13

## Collaborators

- [object Object]

## Primary source

ClinicalTrials.gov registry: https://clinicaltrials.gov/study/NCT04085172

## Citation

> US National Library of Medicine, ClinicalTrials.gov registration NCT04085172, "A Study of TAK-503 in Children and Teenagers With Attention Deficit Hyperactivity Disorder (ADHD)". Retrieved via AI Analytics 2026-05-24 from https://api.ai-analytics.org/clinical/NCT04085172. Licensed CC0.

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