Neuropathy Impairment Score Research Articles

Pure small fiber neuropathy in alcohol dependency detected by skin biopsy.

Alcohol overconsumption is well known to cause damage to the peripheral nervous system. The aim of this study was the functional and structural evaluation of the small nerve fibers in alcohol-dependent subjects, with or without symptoms of peripheral neuropathy. Twenty-six consecutive alcohol-dependent subjects treated for detoxification voluntarily in the specialized unit of the Athens University Psychiatric Clinic were enrolled in this prospective study over 18 months. Every subject was assessed by peripheral nerve evaluation using the Neuropathy Symptoms Score (NSS) and Neuropathy Impairment Score (NIS), followed by nerve conduction studies (NCS), quantitative sensory testing (QST), and skin biopsy. Twenty-nine normal subjects, age- and gender-matched, constituted the control group. Peripheral neuropathy was diagnosed in 16 subjects (61.5%). Among these 16 subjects, pure large fiber neuropathy (LFN) was found in two subjects (12.5%), pure small fiber neuropathy (SFN) was found in eight subjects (50%), and both large and small fiber neuropathy was diagnosed in six patients (37.5%). The intraepidermal nerve fiber density (IENFD) of the patients' skin biopsy was significantly lower than that of the control group. Additionally, QST results showed a statistically significant sensory impairment in the patients. Our study confirms small fiber neuropathy due to alcohol abuse with a high prevalence of pure SFN that might have remained undetected without QST and IENFD.

Treatment response and neurofilament light chain levels with long-term patisiran in hereditary transthyretin-mediated amyloidosis with polyneuropathy: 24-month results of an open-label extension study

Background Longitudinal changes in neurofilament light chain (NfL) levels were evaluated alongside prespecified clinical assessments 24 months into the patisiran Global open-label extension (OLE) study in patients with ATTRv amyloidosis with polyneuropathy. Methods All patients enrolled in the Global OLE, from phase III APOLLO and phase II OLE parent studies, received patisiran. Assessments included measures of polyneuropathy (modified Neuropathy Impairment Score+7 (mNIS+7)), quality of life (QOL; Norfolk QOL-Diabetic Neuropathy questionnaire (Norfolk QOL-DN)), and plasma NfL. Results Patients receiving patisiran in the parent study (APOLLO-patisiran, n = 137; phase II OLE-patisiran, n = 25) demonstrated sustained improvements in mNIS+7 (mean change from parent study baseline (95% confidence interval): APOLLO-patisiran −4.8 (−8.9, −0.6); phase II OLE-patisiran −5.8 (−10.5, −1.2)) and Norfolk QOL-DN (APOLLO-patisiran −2.4 (−7.2, 2.3)), and maintained reduced NfL levels at Global OLE 24 months. After initiating patisiran in the Global OLE, APOLLO-placebo patients (n = 49) demonstrated stabilized mNIS+7, improved Norfolk QOL-DN, and significantly reduced NfL levels. Patisiran continued to demonstrate an acceptable safety profile. Earlier patisiran initiation was associated with a lower exposure-adjusted mortality rate. Conclusions Long-term patisiran treatment led to sustained improvements in neuropathy and QOL, with NfL demonstrating potential as a biomarker for disease progression and treatment response in ATTRv amyloidosis with polyneuropathy.

Quantification of muscle involvement in familial amyloid polyneuropathy using MRI.

Transthyretin familial amyloid polyneuropathy (TTR-FAP) is a rare genetic disease with autosomal-dominant inheritance. In this study, we aimed to quantify fatty infiltration (fat fraction [FF]) and magnetization transfer ratio (MTR) in individual muscles of patients with symptomatic and asymptomatic TTR-FAP using magnetic resonance imaging. Secondarily, we aimed to assess correlations with clinical and electrophysiological variables. A total of 39 patients with a confirmed mutation in the TTR gene (25 symptomatic and 14 asymptomatic) and 14 healthy volunteers were included. A total of 16 muscles were manually delineated in the nondominant lower limb from T1-weighted anatomical images. The corresponding masks were propagated on the MTR and FF maps. Detailed neurological and electrophysiological examinations were conducted in each group. The MTR was decreased (42.6 AU; p = 0.001) and FF was elevated (14%; p = 0.003) in the lower limbs of the symptomatic group, with preferential posterior and lateral involvement. In the asymptomatic group, elevated FF was quantified in the gastrocnemius lateralis muscle (11%; p = 0.021). FF was significantly correlated with disease duration (r = 0.49, p = 0.015), neuropathy impairment score for the lower limb (r = 0.42, p = 0.041), Overall Neuropathy Limitations Scale score (r = 0.49, p = 0.013), polyneuropathy disability score (r = 0.57, p = 0.03) and the sum of compound muscle action potential (r = 0.52, p = 0.009). MTR was strongly correlated to FF (r = 0.78, p < 0.0001), and a few muscles with an FF within the normal range had a reduced MTR. These observations suggest that FF and MTR could be interesting biomarkers in TTR-FAP. In asymptomatic patients, FF in the gastrocnemius lateralis muscle could be a good indicator of the transition from an asymptomatic to a symptomatic form of the disease. MTR could be an early biomarker of muscle alterations.

Treatment characteristics in a cohort of patients with hereditary transthyretin amyloidosis (S7.010)

<h3>Objective:</h3> We aimed to describe and compare treatment modalities in a large cohort of patients with hereditary transthyretin amyloidosis (hATTR) seen at the University of Pennsylvania Amyloidosis Center. <h3>Background:</h3> Treatments for hATTR amyloidosis fall into 2 major categories: transthyretin (TTR) stabilizers (tafamidis and diflunisal) and TTR gene silencers(patisiran and inotersen). Most patients are on one or the other. However, some patients are on both classes of treatment (combination therapy) and there is lack of data to determine whether combination therapy is superior to monotherapy. <h3>Design/Methods:</h3> We performed a retrospective chart review of hATTR patients seen at the University of Pennsylvania between 2018 and 2022. Patient characteristics, treatment, and outcomes were collected and a comparison will be made between the different groups of patients based on treatment modalities. <h3>Results:</h3> 164 patients with hATTR were identified. The most common gene mutations were V122I (87 patients, 53%) and T60A (32 patients, 20%) and V30M (17 patients, 10%). 122 (74%) patients were symptomatic. 47 symptomatic patients (39%) had only cardiac symptoms, 15 patients (12%) had only neurological symptoms, and 60 patients (49%) had a mixed phenotype. 104 (85%) of the symptomatic received treatment, of which 36 (35%) patients received combination therapy with both a gene silencer and protein stabilizer, and 68 (65%) patients received treatment with only one of these medication classes. Statistical analysis comparing cardiac biomarkers and Neuropathy Impairment Scores between patients receiving combination versus monotherapy based on will be performed and presented during the AAN 2023 meeting. <h3>Conclusions:</h3> A significant number of hATTR patients are on both gene silencing and protein stabilizing therapy. There is a lack of data regarding whether patients on combination therapy differ in disease severity compared to those on monotherapy. This study will help bridge this knowledge gap by comparing disease severity and progression between the two groups. <b>Disclosure:</b> Dr. Qarni has nothing to disclose. Mr. Sarmiento Bustamante has nothing to disclose. Dr. Simoes Jones has nothing to disclose. Dr. Khella has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for Ionis. Dr. Khella has received personal compensation in the range of $5,000-$9,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Ionis. Dr. Khella has received personal compensation in the range of $5,000-$9,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Pfizer. Dr. Khella has received personal compensation in the range of $5,000-$9,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Alnylum. Dr. Khella has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Eidos. Brian Drachman has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Alnylam. Brian Drachman has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Akcea. Dr. Pieretti has nothing to disclose. Dr. Karam has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for Alnylam. Dr. Karam has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Ionis. Dr. Karam has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for Sanofi. Dr. Karam has received personal compensation in the range of $10,000-$49,999 for serving as a Consultant for Argenx. Dr. Karam has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Alexion. Dr. Karam has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Neuroderm.

Comparison of Efficacy Outcomes with Vutrisiran vs. Patisiran in hATTR Amyloidosis with Polyneuropathy: Post-hoc Analysis of the HELIOS-A Study (S14.003)

Comparison of Efficacy Outcomes with Vutrisiran vs. Patisiran in hATTR Amyloidosis with Polyneuropathy: Post-hoc Analysis of the HELIOS-A Study (S14.003)

The impact of inotersen on Neuropathy Impairment Score in patients with hereditary transthyretin amyloidosis with polyneuropathy

BackgroundPatients with hereditary transthyretin amyloidosis (ATTRv) frequently experience symptoms of polyneuropathy (PN) that worsen over time and impair daily functioning. Previous analyses supported efficacy of inotersen, an antisense oligonucleotide, to slow neuropathic progression in patients with ATTRv-PN, as indicated by larger mean changes, relative to placebo, in total score and several subscales of the Neuropathy Impairment Score (NIS), and for the subset of NIS items specific to lower limbs (NIS-LL) for the overall study sample. A key objective of the current study was to evaluate efficacy of inotersen for slowing neuropathic progression in NIS/NIS-LL within key clinical subgroups of patients with ATTRv-PN. Additionally, for this study, responder definition (RD) thresholds were estimated for NIS/NIS-LL total and subscale scores, for the purpose of evaluating clinically meaningful benefit of inotersen at the individual patient-level.MethodsPost hoc analyses used data from the NEURO-TTR phase 3 trial of inotersen in patients with ATTRv-PN (NCT01737398). Treatment differences in mean changes on NIS/NIS-LL total and subscale scores from baseline to week 65 were examined within patient subgroups defined by clinical characteristics. Anchor- and distribution-based approaches estimated RDs for NIS/NIS-LL scores, with responders defined as patients who did not experience clinically meaningful neuropathic progression. Responder analyses compared the proportion of patients classified as responders for each NIS/NIS-LL score between treatment arms.ResultsWithin each patient subgroup, mean increases in NIS/NIS-LL total and muscle weakness subscales were significantly smaller after 65 weeks of treatment with inotersen compared to placebo. Similar patterns were observed for some, but not all, subgroups on NIS/NIS-LL reflex subscale scores. Recommended RDs were 8.1 points for NIS total and 4.7 points for NIS-LL total. Patients receiving inotersen for 65 weeks were significantly less likely than those receiving placebo to exhibit clinically meaningful increases on NIS/NIS-LL total, muscle weakness, and sensation subscales.ConclusionsThis study supports previous evidence for efficacy of inotersen in this patient population and provides interpretation guidelines for clinically meaningful changes in NIS/NIS-LL scores.

Problems with classification of polineuropaties severity in case of hereditary ones – review of literature

Evaluation of neuropathy severity is still a challenge for a modern medicine. Many scales were made to resolve this problem but each of them has limitations. It is known that in case of many patients there is no relation between clinical status and nerve conduction studies (NCS) results. Severe disabled patients with neuropathies can have nerve conduction study result mild impaired and conversely relation is also often observed. Many screening instruments with numerous composite scores are used to evaluate neuropathy. Most of them involved sensory perception, motor functions and reflexes like Neuropathy Disability Score (NDS), Neuropathy Impairment Score (NIS), Thoronto Clinical Neuropathy Scoring System. Electrophysiological parameters are also useful in classification of disease types especially in Charcot-Marie-Tooth one. There were many attempts of discovering new scores especially in diabetic neuropathies, involving mainly clinical features. There is lack of easy, reliable and precise scores that could improve neuropathy classification and monitoring disease progression especially in case of hereditary polyneuropathy.

Neuropathic pain experience in symptomatic and presymptomatic subjects carrying a transthyretin gene mutation.

Pain is a common symptom of hereditary transthyretin amyloidosis (ATTRv), however, its occurrence in late-onset ATTRv has not been investigated thoroughly. Our aim was to describe the pain experience and its impact on quality of life (QoL) in symptomatic patients and presymptomatic carriers harboring a transthyretin (TTR) gene mutation with a late-onset phenotype. Study participants (aged ≥18 years) were consecutively recruited from four Italian centers. Clinical disability was assessed using the Familial Amyloid Polyneuropathy (FAP) stage and Neuropathy Impairment Score (NIS). The Norfolk questionnaire evaluated QoL and the Compound Autonomic Dysfunction Test assessed autonomic involvement. Neuropathic pain was screened using the Douleur Neuropathique 4 (DN4) questionnaire, and pain intensity and its impact on daily activity were assessed using the Brief Pain Inventory severity and interference subscores. Data on the type of TTR mutation, presence of cardiomyopathy, treatment, and Body Mass Index (BMI) were collected. Overall, 102 subjects with TTR mutations (mean age ± SD 63.6 ± 13.5 years) were recruited, including 78 symptomatic patients (68.1 ± 10.9 years) and 24 presymptomatic carriers (49 ± 10.3 years). Pain was reported by 75.5% of all subjects, but was more frequent in symptomatic patients than in presymptomatic carriers (85.9 vs. 41.6%, respectively). Pain exhibited neuropathic features (DN4≥4) in 69.2% of symptomatic patients and in 8.3% of presymptomatic carriers. Subjects with neuropathic pain were older (p = 0.015) had worse FAP stage (p < 0.001), higher NIS scores (p < 0.001), greater autonomic involvement (p = 0.003), and a lower QoL (p < 0.001) than those without neuropathic pain. Neuropathic pain was associated with higher pain severity (p < 0.001) and had a significant negative impact on daily activities (p < 0.001) Neuropathic pain was not associated with gender, mutation type, TTR therapy, or BMI. Approximately 70% of late-onset ATTRv patients complained of neuropathic pain (DN4≥4) that worsened as peripheral neuropathy progressed and increasingly interfered with daily activities and QoL. Notably, 8% of presymptomatic carriers complained of neuropathic pain. These results suggest that assessment of neuropathic pain may be useful to monitor disease progression and identify early manifestations of ATTRv.

Patisiran Enhances Muscle Mass after Nine Months of Treatment in ATTRv Amyloidosis: A Study with Bioelectrical Impedance Analysis and Handgrip Strength.

Hereditary transthyretin amyloidosis with polyneuropathy (ATTRv) is caused by mutations in the TTR gene, leading to misfolded monomers that aggregate generating amyloid fibrils. The clinical phenotype is heterogeneous, characterized by a multisystemic disease affecting the sensorimotor, autonomic functions along with other organs. Patisiran is a small interfering RNA acting as a TTR silencer approved for the treatment of ATTRv. Punctual and detailed instrumental biomarkers are on demand for ATTRv to measure the severity of the disease and monitor progression and response to treatment. Fifteen patients affected by ATTRv amyloidosis (66.4 ± 7.8 years, six males) were evaluated before the start of therapy with patisiran and after 9-months of follow-up. The clinical and instrumental evaluation included body weight and height; Coutinho stage; Neuropathy Impairment Score (NIS); Karnofsky performance status (KPS); Norfolk QOL Questionnaire; Six-minute walking test (6 MWT); nerve conduction studies; handgrip strength (HGS); and bioimpedance analysis (BIA). Body composition significantly changed following the 9-months pharmacological treatment. In particular, the patients exhibited an increase in fat free mass, body cell mass, and body weight with a decrease in fat mass. A significant increase after 9 months of treatment was observed for the 6 MWT. Coutinho stage, KPS, NIS, NIS-W, nerve conduction studies, Norfolk, COMPASS-31 scale, and HGS remained unchanged. BIA might represent a useful tool to assess the effects of multiorgan damage in ATTRv and to monitor disease progression and response to treatments. More evidence is still needed for HGS. Patisiran stabilizes polyneuropathy and preserves motor strength by increasing muscle mass after 9 months of treatment.

Characteristics of Patients with Hereditary Transthyretin Amyloidosis-Polyneuropathy (ATTRv-PN) in NEURO-TTRansform, an Open-label Phase 3 Study of Eplontersen.

Hereditary transthyretin (ATTRv) amyloidosis is a rare, severe, progressive, debilitating, and ultimately fatal disease caused by systemic deposition of transthyretin (TTR) amyloid fibrils. ATTRv amyloidosis occurs in both males and females. Eplontersen (ION-682884), a ligand-conjugated antisense oligonucleotide designed to degrade hepatic TTR mRNA, is being evaluated for the treatment of ATTRv amyloidosis with polyneuropathy (ATTRv-PN) in the phase 3, international, multicenter, open-label NEURO-TTRansform study (NCT04136184). To describe the study population of this pivotal trial, here we report the baseline characteristics of patients enrolled in the NEURO-TTRansform study. Patients eligible for NEURO-TTRansform were 18-82years old with a diagnosis of ATTRv-PN and Coutinho stage 1 (ambulatory without assistance) or stage 2 (ambulatory with assistance) disease; documented TTR gene variant; signs and symptoms consistent with neuropathy associated with ATTRv; no prior liver transplant; and New York Heart Association (NYHA) functional class I or II. The NEURO-TTRansform study enrolled 168 patients across 15 countries/territories (North America, 15.5%; Europe, 38.1%; South America/Australia/Asia, 46.4%). At baseline, the study cohort had a mean age of 52.8years, 69.0% of patients were male, and 78.0% of patients were White. The V30M variant was most prevalent (60.1% of patients), and prevalence varied by region. Overall, 56.5% and 17.3% of patients had received previous treatment with tafamidis or diflunisal, respectively. A majority of patients (79.2%) had Coutinho stage 1 disease (unimpaired ambulation) and early (before age 50) disease onset (53.0%). Time from diagnosis to enrollment was 46.6 (57.4) months (mean [standard deviation]). Most patients had a baseline polyneuropathy disability (PND) score of I (40.5%) or II (41.1%), and the mean modified Neuropathy Impairment Score + 7 (mNIS + 7) was 79.0. The recruited population in the ongoing NEURO-TTRansform study has global representation characteristic of contemporary clinical practice. ClinicalTrials.gov identifier NCT04136184.

Axonal loss at time of diagnosis as biomarker for long-term disability in chronic inflammatory demyelinating polyneuropathy.

We hypothesized that early, pretreatment axonal loss would predict long-term disability, supported by a pilot study of selected patients with chronic inflammatory demyelinating polyneuropathy (CIDP). To further test this hypothesis, we examined a larger consecutive group of CIDP patients. Needle electromyography and motor and sensory nerve conduction studies were carried out in 30 CIDP patients at pretreatment and follow-up 5 to 28 years later. Changes in amplitudes were expressed as axonal Z scores and changes in conduction as demyelination Z scores and correlated with findings of the Inflammatory Rasch-built Overall Disability Scale (I-RODS), the Neuropathy Impairment Score (NIS), and isokinetic dynamometry (IKS). At follow-up, the median I-RODS score was 73, the NIS was 23, and the IKS was 56%. The median axonal Z score was unchanged at follow-up. Conversely, the corresponding demyelination Z scores improved. The initial axonal loss was correlated with the clinical outcome and was an independent predictor of outcome by multivariate regression analysis. Axonal loss at follow-up was also correlated with the clinical outcome. Only the follow-up demyelination Z score was correlated with the clinical outcomes. Furthermore, the latency until treatment initiation was predictive of all three clinical outcome scores at follow-up, and of axonal loss and demyelination at follow-up. The present study findings indicate that pretreatment axonal loss at diagnosis in CIDP is predictive of long-term disability, neurological impairment, and strength. A delay in treatment is associated with more pronounced axonal loss and a worse clinical outcome.

Peripheral nerve involvement in wild-type transthyretin amyloidosis.

Neurological involvement other than carpal tunnel syndrome (CTS) has rarely been observed in wild-type transthyretin amyloidosis (ATTRwt). The aim of our study was to investigate peripheral nerve involvement in ATTRwt. Patients diagnosed with ATTRwt (negative molecular testing, confirmed cardiac uptake at bone scintigraphy, Perugini score 2 or 3) were considered. Sixteen men (mean age 75 ± 6.2, range 65-86years) were enrolled. Neurological examination (Neuropathy Impairment Score, NIS), questionnaires on autonomic function and quality of life (QoL), electrodiagnostic studies (EDX), nerve ultrasound, and Sudoscan (electrochemical skin conductance, ESC) were performed. The presence of peripheral neuropathy was defined according to the detection of any abnormal finding at lower limbs other than CTS at EDX studies, regardless of NIS scores. Ten (62.5%) ATTRwt had abnormal NIS scores. At EDX, CTS was observed in 13/16 (81.2%), with 3/16 (18.8%) presenting also axonal peripheral neuropathy. Extensive workup ruled out common causes of neuropathy. Eight (50%) ATTRwt patients had orthostatic hypotension (OH). Abnormal ESC was observed in 9/14 (64%) ATTRwt patients. Despite being uncommon, we observed peripheral nervous system involvement in ATTRwt (large and small fiber dysfunction). Being elderly, ATTRwt patients may have age-related conditions acting as confounding factors for the diagnosis of neuropathy that however can be detected with a careful examination and use of specific tests, including those for autonomic dysfunction.

Effect of RNAi therapeutics patisiran and vutrisiran on orthostatic hypotension due to dysautonomia in patients with hereditary transthyretin-mediated amyloidosis with polyneuropathy

Abstract Background Hereditary transthyretin-mediated (hATTR) amyloidosis, also known as ATTRv amyloidosis, is a rapidly progressive, multisystem disease. Orthostatic hypotension, due to autonomic neuropathy, is a common yet hard-to-treat disease manifestation in patients with hATTR amyloidosis. Fatigue, muscle weakness, and deterioration in cardiac function further exacerbate orthostatic symptoms. Efficacy of RNAi therapeutics patisiran and vutrisiran was assessed in patients with hATTR amyloidosis with polyneuropathy across the APOLLO (NCT01960348), Global Open-Label Extension (OLE) (NCT02510261), and HELIOS-A (NCT03759379) studies, respectively. Purpose Evaluate the quantitative effect of patisiran and vutrisiran on orthostatic hypotension in patients with hATTR amyloidosis with polyneuropathy. Methods In APOLLO, patients were randomised 2:1 to patisiran 0.3 mg/kg or placebo, IV q3w. Patients who completed APOLLO (APOLLO-placebo, APOLLO-patisiran) were eligible to enrol into the ongoing Global OLE (patisiran 0.3 mg/kg IV q3w). In HELIOS-A, patients were randomised 3:1 to vutrisiran (25 mg SC q3m) or patisiran (0.3 mg/kg IV q3w; reference group). Primary endpoint for APOLLO and HELIOS-A was change from baseline in the modified Neuropathy Impairment Score+7 (mNIS+7) vs APOLLO placebo at M18 (APOLLO) and M9 (HELIOS-A). Orthostatic hypotension was evaluated using the postural blood pressure (PBP) component of mNIS+7, calculated as the mean of 2 supine readings of systolic BP [SBP, mmHg] taken 15 min apart minus the lowest SBP upon standing at 1, 3, and 5 min. A smaller reduction in observed SBP between supine and upright readings indicated an improved PBP. Results APOLLO enrolled 225 patients (placebo, n=77; patisiran, n=148), Global OLE 211 and HELIOS-A 164 (vutrisiran, n=122; patisiran, n=42). At baseline, the severity of orthostatic hypotension was similar between within-study treatment arms in APOLLO and HELIOS-A. In APOLLO, patisiran-treated patients showed PBP improvement or stabilization from baseline to M18 (mean [SD] change in SBP: baseline, −17.6 [19.4]; M18, −13.5 [16.8]) and was maintained at Global OLE 36m (−13.4 [15.6]). In contrast, placebo-treated patients in APOLLO had an increased change in PBP over 18m (baseline, −17.5 [16.5]; M18, −20.4 [16.9]); their PBP improved after patisiran initiation (Global OLE 36m, −16.6 [18.1]). In HELIOS-A, stabilization in PBP was observed in the vutrisiran arm (baseline, −11.2 [14.0], M18, −11.7 [14.6]). In the smaller patisiran arm, while the change in PBP increased, the value remained in the normal range (baseline, −11.6 [17.2]; M18, −14.2 [15.5]). Patisiran and vutrisiran have acceptable safety profiles. Conclusions PBP analyses quantify the benefits of RNAi therapeutics patisiran and vutrisiran on autonomic function in patients with hATTR amyloidosis with polyneuropathy. The increase in change in PBP to a symptomatic range without treatment indicates the importance of early intervention. Funding Acknowledgement Type of funding sources: Private company. Main funding source(s): Alnylam Pharmaceuticals

Impact of baseline polyneuropathy severity on patisiran treatment outcomes in the APOLLO trial

Objective Assess how baseline polyneuropathy severity impacts response to patisiran regarding neurologic impairment and quality of life (QOL) in patients with hereditary transthyretin-mediated amyloidosis (ATTRv amyloidosis). Methods This post hoc analysis grouped patients from the Phase 3 APOLLO study (n = 225) by baseline Neuropathy Impairment Score (NIS) into quartiles: 6–<31; 31–<57; 57–<85.5; 85.5–141.6. Neurologic impairment (modified NIS+7 [mNIS+7], NIS total score), disability (Rasch-built Overall Disability Scale [R-ODS]), gait speed (10-meter walk test [10-MWT]), grip strength, and QOL (Norfolk Quality of Life-Diabetic Neuropathy [Norfolk QOL-DN] questionnaire) were assessed. Results Across all baseline NIS quartiles, patisiran improved several clinical markers of disease compared with placebo at 18 months. Patients in lower NIS quartiles, treated with patisiran earlier in the disease course, maintained better scores in mNIS+7, NIS total score, R-ODS, 10-MWT, grip strength, and Norfolk QOL-DN versus those in higher NIS quartiles, while placebo-treated patients experienced worsening of all functional measures after 18 months across all quartiles. Conclusions Patisiran treatment improved neurologic function and QOL across a wide range of baseline polyneuropathy severities versus placebo. Timing of treatment initiation in patients with ATTRv amyloidosis remains critical for the preservation of function. (ClinicalTrials.gov number, NCT01960348)

Muscle quantitative MRI as a novel biomarker in hereditary transthyretin amyloidosis with polyneuropathy: a cross-sectional study

BackgroundThe development of reproducible and sensitive outcome measures has been challenging in hereditary transthyretin (ATTRv) amyloidosis. Recently, quantification of intramuscular fat by magnetic resonance imaging (MRI) has proven as a sensitive marker in patients with other genetic neuropathies. The aim of this study was to investigate the role of muscle quantitative MRI (qMRI) as an outcome measure in ATTRv.MethodsCalf- and thigh-centered multi-echo T2-weighted spin-echo and gradient-echo sequences were obtained in patients with ATTRv amyloidosis with polyneuropathy (n = 24) and healthy controls (n = 12). Water T2 (wT2) and fat fraction (FF) were calculated. Neurological assessment was performed in all ATTRv subjects. Quantitative MRI parameters were correlated with clinical and neurophysiological measures of disease severity.ResultsQuantitative imaging revealed significantly higher FF in lower limb muscles in patients with ATTRv amyloidosis compared to controls. In addition, wT2 was significantly higher in ATTRv patients. There was prominent involvement of the posterior compartment of the thighs. Noticeably, FF and wT2 did not exhibit a length-dependent pattern in ATTRv patients. MRI biomarkers correlated with previously validated clinical outcome measures, Polyneuropathy Disability scoring system, Neuropathy Impairment Score (NIS) and NIS-lower limb, and neurophysiological parameters of axonal damage regardless of age, sex, treatment and TTR mutation.ConclusionsMuscle qMRI revealed significant difference between ATTRv and healthy controls. MRI biomarkers showed high correlation with clinical and neurophysiological measures of disease severity making qMRI as a promising tool to be further investigated in longitudinal studies to assess its role at monitoring onset, progression, and therapy efficacy for future clinical trials on this treatable condition.

Long-term efficacy and safety of inotersen for hereditary transthyretin amyloidosis: NEURO-TTR open-label extension 3-year update

BackgroundHereditary transthyretin amyloidosis (hATTR/ATTRv) results from the deposition of misfolded transthyretin (TTR) throughout the body, including peripheral nerves. Inotersen, an antisense oligonucleotide inhibitor of hepatic TTR production, demonstrated a favorable efficacy and safety profile in patients with the polyneuropathy associated with hATTR in the NEURO-TTR (NCT01737398) study. We report longer-term efficacy and safety data for inotersen, with a median treatment exposure of 3 years.MethodsPatients who satisfactorily completed NEURO-TTR were enrolled in its open-label extension (OLE) study. Efficacy assessments included the modified Neuropathy Impairment Score + 7 (mNIS + 7), Norfolk Quality of Life–Diabetic Neuropathy (Norfolk QoL-DN) questionnaire total score, and the Short Form 36 (SF-36v2) Health Survey Physical Component Summary score. Safety and tolerability were also assessed. Efficacy is reported for patients living in Europe and North America (this cohort completed the study approximately 9 months before the remaining group of patients outside these regions); safety is reported for the full safety dataset, comprising patients living in Europe, North America, and Latin America/Australasia. This study is registered with ClinicalTrials.gov, identifier NCT02175004.ResultsIn the Europe and North America cohort of the NEURO-TTR study, 113/141 patients (80.1%) completed the study, and 109 patients participated in the OLE study. A total of 70 patients continued to receive inotersen (inotersen–inotersen) and 39 switched from placebo to inotersen (placebo–inotersen). The placebo–inotersen group demonstrated sustained improvement in neurological disease progression as measured by mNIS + 7, compared with predicted worsening based on projection of the NEURO-TTR placebo data (estimated natural history). The inotersen–inotersen group demonstrated sustained benefit, as measured by mNIS + 7, Norfolk QoL-DN, and SF-36v2, compared with estimated natural history as well as compared with the placebo–inotersen group. With a maximum exposure of 6.2 years, inotersen was not associated with any additional safety concerns or increased toxicity in the OLE study. Platelet and renal monitoring were effective in reducing the risk of severe adverse events in the OLE study.ConclusionInotersen treatment for > 3 years slowed progression of the polyneuropathy associated with hATTR, and no new safety signals were observed.

Efficacy and safety of vutrisiran for patients with hereditary transthyretin-mediated amyloidosis with polyneuropathy: a randomized clinical trial

Background The study objective was to assess the effect of vutrisiran, an RNA interference therapeutic that reduces transthyretin (TTR) production, in patients with hereditary transthyretin (ATTRv) amyloidosis with polyneuropathy. Methods HELIOS-A was a phase 3, global, open-label study comparing the efficacy and safety of vutrisiran with an external placebo group (APOLLO study). Patients were randomized 3:1 to subcutaneous vutrisiran 25 mg every 3 months (Q3M) or intravenous patisiran 0.3 mg/kg every 3 weeks (Q3W) for 18 months. Results HELIOS-A enrolled 164 patients (vutrisiran, n = 122; patisiran reference group, n = 42); external placebo, n = 77. Vutrisiran met the primary endpoint of change from baseline in modified Neuropathy Impairment Score +7 (mNIS+7) at 9 months (p = 3.54 × 10−12), and all secondary efficacy endpoints; significant improvements versus external placebo were observed in Norfolk Quality of Life-Diabetic Neuropathy, 10-meter walk test (both at 9 and 18 months), mNIS+7, modified body-mass index, and Rasch-built Overall Disability Scale (all at 18 months). TTR reduction with vutrisiran Q3M was non-inferior to within-study patisiran Q3W. Most adverse events were mild or moderate in severity, and consistent with ATTRv amyloidosis natural history. There were no drug-related discontinuations or deaths. Conclusions Vutrisiran significantly improved multiple disease-relevant outcomes for ATTRv amyloidosis versus external placebo, with an acceptable safety profile. ClinicalTrials.gov NCT03759379

Patterns of myelinated nerve fibers loss in transthyretin amyloid polyneuropathy and mimics.

ObjectiveThe present study was intended to analyze the characteristics of myelinated nerve fibers density (MFD) of transthyretin amyloid polyneuropathy (ATTR‐PN) and other similar neuropathies.MethodsA total of 41 patients with ATTR‐PN, 58 patients of other common peripheral neuropathies, and 17 age‐and gender‐matched controls who visited the First Hospital of Peking University and performed sural nerve biopsy between June 2007 and August 2021 were included for analysis of MFD.ResultsExcept the vasculitic neuropathy group, the total and small MFD of patients in the ATTR‐PN group were significantly lower than those of other disease groups. There was an obvious negative correlation between the total MFD and the disease course in the ATTR‐PN group. The disease course of early‐onset and late‐onset symptoms was similar, but the loss of large myelinated nerve fibers (MF) was more severe for the latter. In addition, all late‐onset and most early‐onset patients had severely reduced MFD after a 2 years' disease course. The MFD in ATTR‐PN patients was negatively correlated with Neuropathy Impairment Score (NIS) and Norfolk Quality of life‐diabetic neuropathy (Norfolk QOL‐DN) score.ConclusionMF is lost differently in ATTR‐PN and in other common peripheral neuropathies. The late‐onset and early‐onset ATTR‐PN patients have different patterns of loss of large and small MF.

Patisiran treatment in patients with hereditary transthyretin-mediated amyloidosis with polyneuropathy after liver transplantation

Hereditary transthyretin‐mediated (hATTR) amyloidosis, or ATTRv amyloidosis, is a progressive disease, for which liver transplantation (LT) has been a long‐standing treatment. However, disease progression continues post‐LT. This Phase 3b, open‐label trial evaluated efficacy and safety of patisiran in patients with ATTRv amyloidosis with polyneuropathy progression post‐LT. Primary endpoint was median transthyretin (TTR) reduction from baseline. Twenty‐three patients received patisiran for 12 months alongside immunosuppression regimens. Patisiran elicited a rapid, sustained TTR reduction (median reduction [Months 6 and 12 average], 91.0%; 95% CI: 86.1%–92.3%); improved neuropathy, quality of life, and autonomic symptoms from baseline to Month 12 (mean change [SEM], Neuropathy Impairment Score, −3.7 [2.7]; Norfolk Quality of Life‐Diabetic Neuropathy questionnaire, −6.5 [4.9]; least‐squares mean [SEM], Composite Autonomic Symptom Score‐31, −5.0 [2.6]); and stabilized disability (Rasch‐built Overall Disability Scale) and nutritional status (modified body mass index). Adverse events were mild or moderate; five patients experienced ≥1 serious adverse event. Most patients had normal liver function tests. One patient experienced transplant rejection consistent with inadequate immunosuppression, remained on patisiran, and completed the study. In conclusion, patisiran reduced serum TTR, was well tolerated, and improved or stabilized key disease impairment measures in patients with ATTRv amyloidosis with polyneuropathy progression post‐LT (www.clinicaltrials.gov NCT03862807).

Skeletal Muscle Involvement Pattern of Hereditary Transthyretin Amyloidosis: A Study Based on Muscle MRI.

ObjectsThis study was intended to explore the characteristics of muscle magnetic resonance imaging (MRI) of patients with hereditary transthyretin amyloidosis (ATTRv amyloidosis) prospectively.MethodsThe clinical data of 20 patients with ATTRv amyloidosis at our hospital between July 2020 and August 2021 were analyzed. MRI of lower limbs including calf muscles was performed in all these 20 patients and MRI of thigh muscles was performed in 16 of them.ResultsThe mean age of the 20 patients with ATTRv amyloidosis was 44.2 years (ranging from 26 to 60) whose mean duration of weakness was 23.3 ± 23.0 (ranging from 0 to 84) months. All the patients presented with polyneuropathy, and 18 of them with weakness in their lower limbs. Muscle involvement was selective in these patients with ATTRv amyloidosis. The posterior group of muscles was heavily fatty, and the soleus muscle was the most heavily involved. The proportion of fatty infiltration scores at the calf level was higher than at the thigh level with paired comparison for most patients. Three of these patients had more severely fatty infiltration of muscles at the thigh level. The fatty infiltration of posterior compartments at the calf level was highly consistent with neuropathy impairment scores of lower limbs (weakness), the strength of ankle plantar flexion muscles, and the amplitude of the compound muscle action potential of the tibial nerve.ConclusionsIt was found that the pattern of muscle fatty infiltration was consistent with a distal-to-proximal gradient on the whole and that proximal involvements in MRI of lower limbs in some patients could also be observed. Selective fatty infiltration of muscles of posterior compartments and fatty infiltration of the soleus muscle might be typical of ATTRv amyloidosis.