Pilot trial of inosine to elevate urate levels in amyotrophic lateral sclerosis.

OBJECTIVE: To test the safety, tolerability, and urate-elevating capability of the urate precursor inosine taken orally or by feeding tube in people with amyotrophic lateral sclerosis (ALS). METHODS: This was a pilot, open-label trial in 25 participants with ALS. Treatment duration was 12 weeks. The dose of inosine was titrated at pre-specified time points to elevate serum urate levels to 7-8 mg/dL. Primary outcomes were safety (as assessed by the occurrence of adverse events [AEs]) and tolerability (defined as the ability to complete the 12-week study on study drug). Secondary outcomes included biomarkers of oxidative stress and damage. As an exploratory analysis, observed outcomes were compared with a virtual control arm built using prediction algorithms to estimate ALSFRS-R scores. RESULTS: Twenty-four out of 25 participants (96%) completed 12 weeks of study drug treatment. One participant was unable to comply with study visits and was lost to follow-up. Serum urate rose to target levels in 6 weeks. No serious AEs attributed to study drug and no AEs of special concern, such as urolithiasis and gout, occurred. Selected biomarkers of oxidative stress and damage had significant changes during the study period. Observed changes in ALSFRS-R did not differ from baseline predictions. INTERPRETATION: Inosine appeared safe, well tolerated, and effective in raising serum urate levels in people with ALS. These findings, together with epidemiological observations and preclinical data supporting a neuroprotective role of urate in ALS models, provide the rationale for larger clinical trials testing inosine as a potential disease-modifying therapy for ALS.

Phase IIa trial of fingolimod for amyotrophic lateral sclerosis demonstrates acceptable acute safety and tolerability.

INTRODUCTION: Immune activation has been implicated in progression of amytrophic lateral sclerosis (ALS). Oral fingolimod reduces circulating lymphocytes. The objective of this phase IIa, randomized, controlled trial was to test the short-term safety, tolerability, and target engagement of fingolimod in ALS. METHODS: Randomization was 2:1 (fingolimod:placebo). Treatment duration was 4 weeks. Primary outcomes were safety and tolerability. Secondary outcomes included circulating lymphocytes and whole-blood gene expression. RESULTS: Thirty participants were randomized; 28 were administered a drug (fingolimod 18, placebo 10). No serious adverse events occurred. Adverse events were similar by treatment arm, as was study discontinuation (2 fingolimod vs. 0 placebo, with no statistical difference). Forced expiratory volume in 1 second (FEV1 ) and FEV1 /slow vital capacity changes were similar in the fingolimod and placebo arms. Circulating lymphocytes decreased significantly in the fingolimod arm (P < 0.001). Nine immune-related genes were significantly downregulated in the fingolimod arm, including forkhead box P3 (P < 0.001) and CD40 ligand (P = 0.003). DISCUSSION: Fingolimod is safe and well-tolerated and can reduce circulating lymphocytes in ALS patients. Muscle Nerve 56: 1077-1084, 2017.

A high-density genome-wide association screen of sporadic ALS in US veterans.

Following reports of an increased incidence of amyotrophic lateral sclerosis (ALS) in U.S. veterans, we have conducted a high-density genome-wide association study (GWAS) of ALS outcome and survival time in a sample of U.S. veterans. We tested ∼1.3 million single nucleotide polymorphisms (SNPs) for association with ALS outcome in 442 incident Caucasian veteran cases diagnosed with definite or probable ALS and 348 Caucasian veteran controls. To increase power, we also included genotypes from 5909 publicly-available non-veteran controls in the analysis. In the survival analysis, we tested for association between SNPs and post-diagnosis survival time in 639 Caucasian veteran cases with definite or probable ALS. After this discovery phase, we performed follow-up genotyping of 299 SNPs in an independent replication sample of Caucasian veterans and non-veterans (ALS outcome: 183 cases and 961 controls; survival: 118 cases). Although no SNPs reached genome-wide significance in the discovery phase for either phenotype, three SNPs were statistically significant in the replication analysis of ALS outcome: rs6080539 (177 kb from PCSK2), rs7000234 (4 kb from ZNF704), and rs3113494 (13 kb from LOC100506746). Two SNPs located in genes that were implicated by previous GWA studies of ALS were marginally significant in the pooled analysis of discovery and replication samples: rs17174381 in DPP6 (p = 4.4×10(-4)) and rs6985069 near ELP3 (p = 4.8×10(-4)). Our results underscore the difficulty of identifying and convincingly replicating genetic associations with a rare and genetically heterogeneous disorder such as ALS, and suggest that common SNPs are unlikely to account for a substantial proportion of patients affected by this devastating disorder.

Clinical significance in the change of decline in ALSFRS-R.

Our objective was to survey ALS clinicians and researchers regarding what percentage reduction in the ALSFRS-R (Amyotrophic Lateral Sclerosis Functional Rating Scale - Revised) slope they would consider clinically meaningful. A nine-question survey was provided to 65 members of the Northeast ALS Consortium (NEALS). They were asked to rate the clinical relevance of 10-50% changes in decline of the ALSFRS-R slope on a seven-point scale (1-7), where 1='not at all clinically meaningful', 4='somewhat clinically meaningful', and 7='very clinically meaningful'. Ninety per cent of participants rated a 20% change in the decline of the ALSFRS-R score as the percentage in which a somewhat clinically significant change starts to be noted (i.e. score of 4 or higher). All participants endorsed a 25% or higher change in the ALSFRS-R score as at least somewhat clinically meaningful (score of 4 or higher). Ninety-three per cent of the participants viewed a 50% change in decline as very clinically meaningful (score of 7). This survey demonstrated that the majority of clinicians and clinical researchers surveyed believe that a therapy that resulted in a change of 20% or greater in the slope of the ALSFRS-R would be clinically meaningful.