# SPINRAZA Clinical Trial Data
Keywords: SMA, SPINRAZA, Type II, Type III, 6-Minute Walk Test, HFMSE, clinical trial, safety, efficacy

> This page provides detailed information about the clinical trial data for SPINRAZA, focusing on its efficacy and safety in treating patients with Type II and Type III spinal muscular atrophy (SMA), including improvements in mobility and walking distance.

## Details
- [Natural History of Untreated SMA](#): Individuals with later-onset SMA (Type III) experience an average annual decline of 1.5 meters in the 6-Minute Walk Test (6MWT).
- [Ambulatory Improvements with SPINRAZA](#): SPINRAZA demonstrated sustained improvements in walking distance for ambulatory SMA patients, with notable gains over a 1050-day period.
- [6-Minute Walk Test (6MWT)](#): A reliable clinical measure for SMA patients, assessing walking distance over six minutes to evaluate daily activity performance.
- [Study Description](#): Phase I-II studies (CS2 and CS12) evaluated SPINRAZA's safety and efficacy in Type II and III SMA patients over approximately 3 years, showing significant functional improvements.
- [Adverse Event Reporting](#): Instructions for reporting adverse events in the UK and Ireland, including contact details for Biogen and regulatory authorities.