Researchers at The National Institute of Health have recently selected SMA as the prototype for their accelerated drug discovery effort, singled out as the condition closest to treatment out of 600 neurological diseases.
Leading researchers estimate a treatment for SMA could be reached in five years with funding of twenty to thirty million dollars annually.

There are several clinical trials recruiting, information can be found at

Clinical Trials.Gov 

Information can also be found at several networks

MDA for Strength, Independence & Life
Pediatric Neuromuscular Clinical Research Network (PNCR) 

Treat-NMD Neuromuscular Network

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