Safety and efficacy of arimoclomol in patients with early amyotrophic lateral sclerosis (ORARIALS-01): a randomised, double-blind, placebo-controlled, multicentre, phase 3 trial.

BACKGROUND: Amyotrophic lateral sclerosis is a progressive neurodegenerative disorder leading to muscle weakness and respiratory failure. Arimoclomol, a heat-shock protein-70 (HSP70) co-inducer, is neuroprotective in animal models of amyotrophic lateral sclerosis, with multiple mechanisms of action, including clearance of protein aggregates, a pathological hallmark of sporadic and familial amyotrophic lateral sclerosis. We aimed to evaluate the safety and efficacy of arimoclomol in patients with amyotrophic lateral sclerosis. METHODS: ORARIALS-01 was a multinational, randomised, double-blind, placebo-controlled, parallel-group trial done at 29 centres in 12 countries in Europe and North America. Patients were eligible if they were aged 18 years or older and met El Escorial criteria for clinically possible, probable, probable laboratory-supported, definite, or familial amyotrophic lateral sclerosis; had an ALS Functional Rating Scale-Revised score of 35 or more; and had slow vital capacity at 70% or more of the value predicted on the basis of the participant's age, height, and sex. Patients were randomly assigned (2:1) in blocks of 6, stratified by use of a stable dose of riluzole or no riluzole use, to receive oral arimoclomol citrate 1200 mg/day (400 mg three times per day) or placebo. The Randomisation sequence was computer generated centrally. Investigators, study personnel, and study participants were masked to treatment allocation. The primary outcome was the Combined Assessment of Function and Survival (CAFS) rank score over 76 weeks of treatment. The primary outcome and safety were analysed in the modified intention-to-treat population. This trial is registered with ClinicalTrials.gov, NCT03491462, and is completed. FINDINGS: Between July 31, 2018, and July 17, 2019, 287 patients were screened, 245 of whom were enrolled in the trial and randomly assigned. The modified intention-to-treat population comprised 239 patients (160 in the arimoclomol group and 79 in the placebo group): 151 (63%) were male and 88 (37%) were female; mean age was 57·6 years (SD 10·9). CAFS score over 76 weeks did not differ between groups (mean 0·51 [SD 0·29] in the arimoclomol group vs 0·49 [0·28] in the placebo group; p=0·62). Cliff's delta comparing the two groups was 0·039 (95% CI -0·116 to 0·194). Proportions of participants who died were similar between the treatment groups: 29 (18%) of 160 patients in the arimoclomol group and 18 (23%) of 79 patients in the placebo group. Most deaths were due to disease progression. The most common adverse events were gastrointestinal. Adverse events were more often deemed treatment-related in the arimoclomol group (104 [65%]) than in the placebo group (41 [52%]) and more often led to treatment discontinuation in the arimoclomol group (26 [16%]) than in the placebo group (four [5%]). INTERPRETATION: Arimoclomol did not improve efficacy outcomes compared with placebo. Although available biomarker data are insufficient to preclude future strategies that target the HSP response, safety data suggest that a higher dose of arimoclomol would not have been tolerated. FUNDING: Orphazyme.

Open-Label, Multicenter, Phase III Extension Study of Idalopirdine as Adjunctive to Donepezil for the Treatment of Mild-Moderate Alzheimer's Disease.

This open-label extension study evaluated the long-term safety and tolerability of idalopirdine 60 mg/day as adjunctive therapy in patients with mild-moderate Alzheimer's disease (AD). This extension study was a continuation of Studies 1 and 2 of the Phase III development program for idalopirdine and comprised a 28-week open-label treatment period ("OLEX") and a subsequent 24-week open-label treatment period with memantine ("MEMOLEX") in selected patients. The previous studies had shown no evidence of efficacy with idalopirdine as adjunctive treatment to donepezil but with good tolerability (of 1,791 patients randomized, 1,609 [90%] completed the double-blind studies). Of those, 1,463 patients (91%) entered the open-label extension study. During the 28-week OLEX period, the percentage of patients having treatment-emergent adverse events (TEAEs) ranged between 51% and 59% across the treatment groups originating from the lead-in studies. During the subsequent 24-week MEMOLEX period, 51% of the patients had TEAEs. Increases in liver enzymes (occurring in 1-3% of trial participants) were transient and no new safety signals were observed with longer term exposure. No consistent effects demonstrating benefits with idalopirdine were observed on efficacy parameters when patients transitioned to 60 mg in the extension study. Overall, idalopirdine was safe and well tolerated when added to donepezil, and when memantine was added to a prior combination of idalopirdine and donepezil. There were no new safety signals observed with up to 18 months of exposure at the described doses to idalopirdine.

Wide spectrum modulation by KP-544 in models relevant for neuronal survival.

Reduced neurotrophic signalling has been proposed as a part of the pathophysiology behind neuronal death and dysfunction. The small molecule KP-544 was developed with the intention to enhance nerve growth factor signalling. To characterize the actions of KP-544 pharmacologically, we used four diverse models with relevance for neuronal function and survival. We found that 300-1000 nM KP-544 enhanced the neurite outgrowth in PC12 cells in response to a suboptimal concentration of nerve growth factor. KP-544 also protected the cerebellar granule cells from excitotoxicity apoptosis induced by the mitochondrial toxin methyl-phenyl-pyridinium, and modulated inflammation by inhibiting interleukin-6 production in primary astrocytes. Chronic treatment of rats with KP-544 prevented the hyper-responsiveness to amphetamine of animals treated with methylazoxymethanol acetate, a recently described neurodevelopmental model of schizophrenia.