NCT01645787.

Methods	Randomised, double‐blind, placebo‐controlled cross‐over trial
Participants	12 participants with SMA type III, aged 18–50 years
Interventions	4‐AP 10 mg twice daily or placebo twice daily Short‐term treatment trial in which participants are treated for 2 weeks with 4‐AP and placebo in random sequence followed by a long treatment trial of 6 weeks in which participants are also treated with placebo and 4‐AP.
Outcomes	6MWT, Hammersmith Functional Motor Scale Expanded, manual muscle testing, change in motor unit estimation and nerve conduction studies
Notes	Study completed (September 2015), but no results available yet.