Pharmacological treatment for familial amyloid polyneuropathy

Background: Disease‐modifying pharmacological agents for transthyretin (TTR)‐related familial amyloid polyneuropathy (FAP) have become available in the last decade, but evidence on their efficacy and safety is limited. This review focuses on disease‐modifying pharmacological treatment for TTR‐related and other FAPs, encompassing amyloid kinetic stabilisers, amyloid matrix solvents, and amyloid precursor inhibitors. Objectives: To assess and compare the efficacy, acceptability, and tolerability of disease‐modifying pharmacological agents for familial amyloid polyneuropathies (FAPs). Search methods: On 18 November 2019, we searched the Cochrane Neuromuscular Specialised Register, the Cochrane Central Register of Controlled Trials, MEDLINE, and Embase. We reviewed reference lists of articles and textbooks on peripheral neuropathies. We also contacted experts in the field. We searched clinical trials registries and manufacturers' websites. Selection criteria: We included randomised clinical trials (RCTs) or quasi‐RCTs investigating any disease‐modifying pharmacological agent in adults with FAPs. Disability due to FAP progression was the primary outcome. Secondary outcomes were severity of peripheral neuropathy, change in modified body mass index (mBMI), quality of life, severity of depression, mortality, and adverse events during the trial. Data collection and analysis: We followed standard Cochrane methodology. Main results: The review included four RCTs involving 655 people with TTR‐FAP. The manufacturers of the drugs under investigation funded three of the studies. The trials investigated different drugs versus placebo and we did not conduct a meta‐analysis. One RCT compared tafamidis with placebo in early‐stage TTR‐FAP (128 randomised participants). The trial did not explore our predetermined disability outcome measures. After 18 months, tafamidis might reduce progression of peripheral neuropathy slightly more than placebo (Neuropathy Impairment Score (NIS) in the lower limbs; mean difference (MD) ‐3.21 points, 95% confidential interval (CI) ‐5.63 to ‐0.79; P = 0.009; low‐certainty evidence). However, tafamidis might lead to little or no difference in the change of quality of life between groups (Norfolk Quality of Life‐Diabetic Neuropathy (Norfolk QOL‐DN) total score; MD ‐4.50 points, 95% CI ‐11.27 to 2.27; P = 0.19; very low‐certainty evidence). No clear between‐group difference was found in the numbers of participants who died (risk ratio (RR) 0.65, 95% CI 0.11 to 3.74; P = 0.63; very low‐certainty evidence), who dropped out due to adverse events (RR 1.29, 95% CI 0.30 to 5.54; P = 0.73; very low‐certainty evidence), or who experienced at least one severe adverse event during the trial (RR 1.16, 95% CI 0.37 to 3.62; P = 0.79; very low‐certainty evidence). One RCT compared diflunisal with placebo (130 randomised participants). At month 24, diflunisal might reduce progression of disability (Kumamoto Score; MD ‐4.90 points, 95% CI ‐7.89 to ‐1.91; P = 0.002; low‐certainty evidence) and peripheral neuropathy (NIS plus 7 nerve tests; MD ‐18.10 points, 95% CI ‐26.03 to ‐10.17; P < 0.001; low‐certainty evidence) more than placebo. After 24 months, changes from baseline in the quality of life measured by the 36‐Item Short‐Form Health Survey score showed no clear difference between groups for the physical component (MD 6.10 points, 95% CI 2.56 to 9.64; P = 0.001; very low‐certainty evidence) and the mental component (MD 4.40 points, 95% CI ‐0.19 to 8.99; P = 0.063; very low‐certainty evidence). There was no clear between‐group difference in the number of people who died (RR 0.46, 95% CI 0.15 to 1.41; P = 0.17; very low‐certainty evidence), in the number of dropouts due to adverse events (RR 2.06, 95% CI 0.39 to 10.87; P = 0.39; very low‐certainty evidence), and in the number of people who experienced at least one severe adverse event (RR 0.77, 95% CI 0.18 to 3.32; P = 0.73; very low‐certainty evidence) during the trial. One RCT compared patisiran with placebo (225 randomised participants). After 18 months, patisiran reduced both progression of disability (Rasch‐built Overall Disability Scale; least‐squares MD 8.90 points, 95% CI 7.00 to 10.80; P < 0.001; moderate‐certainty evidence) and peripheral neuropathy (modified NIS plus 7 nerve tests ‐ Alnylam version; least‐squares MD ‐33.99 points, 95% CI ‐39.86 to ‐28.13; P < 0.001; moderate‐certainty evidence) more than placebo. At month 18, the change in quality of life between groups favoured patisiran (Norfolk QOL‐DN total score; least‐squares MD ‐21.10 points, 95% CI ‐27.20 to ‐15.00; P < 0.001; low‐certainty evidence). There was little or no between‐group difference in the number of participants who died (RR 0.61, 95% CI 0.21 to 1.74; P = 0.35; low‐certainty evidence), dropped out due to adverse events (RR 0.33, 95% CI 0.13 to 0.82; P = 0.017; low‐certainty evidence), or experienced at least one severe adverse event (RR 0.91, 95% CI 0.64 to 1.28; P = 0.58; low‐certainty evidence) during the trial. One RCT compared inotersen with placebo (172 randomised participants). The trial did not explore our predetermined disability outcome measures. From baseline to week 66, inotersen reduced progression of peripheral neuropathy more than placebo (modified NIS plus 7 nerve tests ‐ Ionis version; MD ‐19.73 points, 95% CI ‐26.50 to ‐12.96; P < 0.001; moderate‐certainty evidence). At week 65, the change in quality of life between groups favoured inotersen (Norfolk QOL‐DN total score; MD ‐10.85 points, 95% CI ‐17.25 to ‐4.45; P < 0.001; low‐certainty evidence). Inotersen may slightly increase mortality (RR 5.94, 95% CI 0.33 to 105.60; P = 0.22; low‐certainty evidence) and occurrence of severe adverse events (RR 1.48, 95% CI 0.85 to 2.57; P = 0.16; low‐certainty evidence) compared to placebo. More dropouts due to adverse events were observed in the inotersen than in the placebo group (RR 8.57, 95% CI 1.16 to 63.07; P = 0.035; low‐certainty evidence). There were no studies addressing apolipoprotein AI‐FAP, gelsolin‐FAP, and beta‐2‐microglobulin‐FAP. Authors' conclusions Evidence on the pharmacological treatment of FAPs from RCTs is limited to TTR‐FAP. No studies directly compare disease‐modifying pharmacological treatments for TTR‐FAP. Results from placebo‐controlled trials indicate that tafamidis, diflunisal, patisiran, and inotersen may be beneficial in TTR‐FAP, but further investigations are needed. Since direct comparative studies for TTR‐FAP will be hampered by sample size and costs required to demonstrate superiority of one drug over another, long‐term non‐randomised open‐label studies monitoring their efficacy and safety are needed

Pharmacological treatment for familial amyloid neuropathy

This is a protocol for a Cochrane Review (Intervention). The objectives are as follows: To assess and compare the efficacy, acceptability, and tolerability of pharmacologic disease‐modifying agents for familial amyloid neuropathy (FAP)

Restless Legs Syndrome: Known Knowns and Known Unknowns

Although restless legs syndrome (RLS) is a common neurological disorder, it remains poorly understood from both clinical and pathophysiological perspectives. RLS is classified among sleep-related movement disorders, namely, conditions characterized by simple, often stereotyped movements occurring during sleep. However, several clinical, neurophysiological and neuroimaging observations question this view. The aim of the present review is to summarize and query some of the current concepts (known knowns) and to identify open questions (known unknowns) on RLS pathophysiology. Based on several lines of evidence, we propose that RLS should be viewed as a disorder of sensorimotor interaction with a typical circadian pattern of occurrence, possibly arising from neurochemical dysfunction and abnormal excitability in different brain structures

Huntington disease-like phenotype in a patient with ANO3 mutation

A 71-year-old previously well white British female developed progressive involuntary tongue movements over one year, resulting in eating difficulty and 10 kg weight loss. She had also noted involuntary perioral, facial and distal limb movements beginning 18 months earlier. These had progressively worsened. In the 3 years prior to presentation, she reported subjective memory decline, word finding difficulty and depressed mood, which improved with mirtazapine 30 mg once daily. She had no history of neuroleptic exposure. Her brother had died aged 40 years, following years of mental illness and substance abuse. She was estranged from her father, who was said to have had ‘behavioural problems’. Her paternal grandmother and maternal aunt had Parkinson's disease

A fluorescent perilipin 2 knock-in mouse model visualizes lipid droplets in the developing and adult brain

Lipid droplets (LDs) are dynamic lipid storage organelles. They are tightly linked to metabolism and can exert protective functions, making them important players in health and disease. Most LD studies in vivo rely on staining methods, providing only a snapshot. We therefore developed a LD-reporter mouse by endogenously labelling the LD coat protein perilipin 2 (PLIN2) with tdTomato, enabling staining-free fluorescent LD visualisation in living and fixed tissues and cells. Here we validate this model under standard and high-fat diet conditions and demonstrate that LDs are present in various cells in the healthy brain, including neurons, astrocytes, ependymal cells, neural stem/progenitor cells and microglia. Furthermore, we show that LDs are abundant during brain development and can be visualized using live-imaging of embryonic slices. Taken together, our tdTom-Plin2 mouse serves as a novel tool to study LDs and their dynamics under both physiological and diseased conditions in all tissues expressing Plin2

Four-week trunk-specific exercise program decreases forward trunk flexion in Parkinson's disease: A single-blinded, randomized controlled trial

INTRODUCTION: Pathological forward trunk flexion is a disabling and drug-refractory motor complication of Parkinson's disease (PD) leading to imbalance, pain, and fall-related injuries. Since it might be reversible, early and multidisciplinary management is emphasised. The primary aim was to compare the effects of a four-week trunk-specific rehabilitation program on the severity of the forward trunk flexion. The secondary aim was to compare the training effects on the motor impairments, dynamic and static balance, pain, falls, and quality of life. METHODS: 37 patients with PD (H&Y\u202f 64\u202f4) and forward trunk flexion were randomized in the experimental (n\u202f=\u202f19) or control group (n\u202f=\u202f18). The former consisted of active self-correction exercises with visual and proprioceptive feedback, passive and active trunk stabilization exercises and functional tasks. The latter consisted of joint mobilization, muscle strengthening and stretching, gait and balance exercises. Protocols lasted 4 weeks (60\u202fmin/day, 5 days/week). Before, after, and at 1-month follow-up, a blinded examiner evaluated patients using primary and secondary outcomes. The primary outcome was the forward trunk flexion severity (degree). Secondary outcomes were the UPDRS III, dynamic and static balance, pain falls, and quality of life assessment. RESULTS: The experimental group reported a significantly greater reduction in forward trunk flexion than the control group from T0 to both T1 (p\u202f=\u202f0.003) and T2 (p\u202f=\u202f0.004). The improvements in dynamic and static balance were significantly greater for the experimental group than the control group from T0 to T2 (p\u202f=\u202f0.017 and 0.004, respectively). Comparable effects were reported on the other outcomes. Pre-treatment forward trunk flexion values were highly correlated to post-treatment trunk deviation changes. CONCLUSION: The four-week trunk-specific rehabilitation training decreased the forward trunk flexion severity and increased postural control in patients with PD. NCT03741959