Heat shock and the ALS models also served as initiating stresses to evaluate the HSP co-inducer, arimoclomol, which is in clinical trial for ALS and inclusion body myositis and exhibits a favorable safety profile (Lanka et al. 2009), as well as to determine if efficacy would be increased by combination with an HDAC inhibitor. This evidence concerns the gene HDAC9 and amyotrophic lateral sclerosis.