The Val30Met familial amyloid polyneuropathy specific Rasch-built overall disability scale (FAP-RODS(©) )

Patient-Reported Outcome Measures for Assessing Health-Related Quality of Life in Patients With Polyneuropathies, Focusing on Guillain-Barré Syndrome and Chronic Inflammatory Demyelinating Polyneuropathy: A Systematic Review of Measurement Properties

Guillain-Barre syndrome (GBS) and chronic inflammatory demyelinating polyneuropathy (CIDP) are immune-mediated peripheral neuropathies. Despite treatment, patients may report residual deficits, pain, and fatigue with considerable impact on quality of life. A systematic review was conducted of the methodological quality of current patient-reported outcome measures (PROMs) for measuring health-related quality of life (HRQoL) in patients with GBS and CIDP. A literature search was conducted in EMBASE, MEDLINE, Web of Science, and Google Scholar. PROMs developed to measure (aspects of) HRQoL in patients with polyneuropathy were classified using the Wilson and Cleary model. Measurement properties were evaluated in accordance with Consensus-based Standards for selection of health Measurement Instruments (COSMIN) guideline. A total of 57 articles identified 31 unique PROMs that are used for measuring HRQoL in patients with polyneuropathies. Of these, 22 measured symptom status, 19 functional status, and 4 general health perception. Eight PROMs were developed or validated in patients with GBS/CIDP. None of the PROMs demonstrated sufficient content validity for recommendation in this population. Only the Rasch-built Fatigue Severity Scale (R-FSS) performed sufficiently across all other measurement properties. The Inflammatory Rasch-built Overall Disability Scale (I-RODS) and IN-QoL are not recommended for use because of insufficient construct validity. GBS Patient Experience Questionnaire, Chronic Acquired Polyneuropathy Patient-Reported Index (CAP-PRI), Fatigue Severity Scale (FSS), R-FSS, Rotterdam Handicap Scale (RHS) and the 36-Item Short Form Health Survey (SF-36) need further validation. PROMs of good quality assessing all relevant aspects of HRQoL are required for better insight in HRQoL in patients with GBS and CIDP.

Hereditary Transthyretin Amyloidosis with Polyneuropathy: Monitoring and Management

Our aim in this review is to discuss current treatments and investigational products and their effect on patients with hereditary transthyretin amyloidosis with polyneuropathy (ATTRv-PN) and provide suggestions for monitoring disease progression and treatment efficacy.

Guidelines and new directions in the therapy and monitoring of ATTRv amyloidosis

The recent approval of three drugs for the treatment of amyloid transthyretin (ATTR) amyloidosis, both hereditary and wild-type, has opened a new era in the care of these diseases. ATTR amyloidosis is embedded in its pathophysiology, and the drugs target critical steps of the amyloid cascade. In addition to liver transplant, which removes the pathogenic variants, the introduction of gene silencers has allowed the suppression of both wild type and mutant transthyretin (TTR), thus extending the potential therapeutic range to wild-type cardiac amyloidosis. The kinetic stabilisation of TTR using small molecules has proved to be clinically effective both for amyloid neuropathy and cardiomyopathy. Gene silencers and kinetic stabilizers were recently approved on the basis of the outcome of phase III trials; however, comparative trials have not been performed, making it difficult to draw recommendations. Indications for liver transplantation have narrowed considerably. Here, guidelines for therapy are proposed based on expert consensus, acknowledging that the several drugs currently undergoing clinical trials will probably change in the near future the therapeutic armamentarium and, consequently, the therapeutic strategy. Indications for monitoring disease progression and drug efficacy are also provided for the management of these complexes, but now very treatable, diseases.

Quality of life assessment in amyloid transthyretin (ATTR) amyloidosis

BACKGROUND

Amyloid transthyretin (ATTR) amyloidosis is caused by the systemic deposition of transthyretin molecules, either normal (wild-type ATTR, ATTRwt) or mutated (variant ATTR, ATTRv). ATTR amyloidosis is a disease with a severe impact on patients' quality of life (QoL). Nonetheless, limited attention has been paid to QoL so far, and no specific tools for QoL assessment in ATTR amyloidosis currently exist. QoL can be evaluated through patient-reported outcome measures (PROMs), which are completed by patients, or through scales, which are compiled by clinicians. The scales investigate QoL either directly or indirectly, i.e., by assessing the degree of functional impairment and limitations imposed by the disease.

DESIGN

Search for the measures of QoL evaluated in phase 2 and phase 3 clinical trials on ATTR amyloidosis.

RESULTS

Clinical trials on ATTR amyloidosis have used measures of general health status, such as the Short Form 36 Health Survey (SF-36), or tools developed in other disease settings such as the Kansas City Cardiomyopathy Questionnaire (KCCQ) or adaptations of other scales such as the modified Neuropathy Impairment Score +7 (mNIS+7).

CONCLUSIONS

Scales or PROMs for ATTR amyloidosis would be useful to better characterize newly diagnosed patients and to assess disease progression and response to treatment. The ongoing ITALY (Impact of Transthyretin Amyloidosis on Life qualitY) study aims to develop and validate 2 PROMs encompassing the whole phenotypic spectrum of ATTRwt and ATTRv amyloidosis, that might be helpful for patient management and may serve as surrogate endpoints for clinical trials.

Canadian Guidelines for Hereditary Transthyretin Amyloidosis Polyneuropathy Management

Hereditary transthyretin-mediated (hATTR) amyloidosis is a progressive disease caused by mutations in the TTR gene leading to multisystem organ dysfunction. Pathogenic TTR aggregation, misfolding, and fibrillization lead to deposition of amyloid in multiple body organs and frequently involve the peripheral nerve system and the heart. Common neurologic manifestations include: sensorimotor polyneuropathy (PN), autonomic neuropathy, small-fiber PN, and carpal tunnel syndrome. Many patients have significant progression due to diagnostic delays as hATTR PN is not considered within the differential diagnosis. Recently, two effective novel disease-modifying therapies, inotersen and patisiran, were approved by Health Canada for the treatment of hATTR PN. Early diagnosis is crucial for the timely introduction of these disease-modifying treatments that reduce impairments, improve quality of life, and extend survival. In this guideline, we aim to improve awareness and outcomes of hATTR PN by making recommendations directed to the diagnosis, monitoring, and treatment in Canada.

Quality of life outcomes in APOLLO, the phase 3 trial of the RNAi therapeutic patisiran in patients with hereditary transthyretin-mediated amyloidosis

Introduction: Hereditary transthyretin-mediated (hATTR) amyloidosis is a rare, fatal, multisystem disease leading to deteriorating quality of life (QOL). The impact of patisiran on QOL in patients with hATTR amyloidosis with polyneuropathy from the phase 3 APOLLO study (NCT01960348) is evaluated.Methods: Patients received either patisiran 0.3 mg/kg (n = 148) or placebo (n = 77) intravenously once every three weeks for 18 months. Multiple measures were used to assess varying aspects of QOL.Results: At 18 months, compared with placebo, patisiran improved Norfolk Quality of Life-Diabetic Neuropathy (Norfolk QOL-DN) score; (least squares [LS] mean difference: -21.1; p = 1.10 × 10^-10; improved across all domains), EuroQoL 5-dimensions 5-levels (LS mean difference: 0.2; p = 1.4 × 10^-12), EuroQoL-visual analog scale (LS mean difference: 9.5; p=.0004), Rasch-built Overall Disability Scale (LS mean difference: 9.0; p = 4.07 × 10^-16) and Composite Autonomic Symptom Score-31(COMPASS-31; LS mean difference: -7.5; p=.0008). Placebo-treated patients experienced rapid QOL deterioration; treatment effects for patisiran were observed as early as 9 months. At 18 months, patisiran improved Norfolk QOL-DN total score and three individual domains as well as COMPASS-31 total scores relative to baseline. Consistent benefits were also observed in the cardiac subpopulation.Conclusion: The benefits of patisiran across all QOL measures and the rapid deterioration observed with placebo, highlight the urgency in early treatment for patients with hATTR amyloidosis with polyneuropathy.

Expert consensus recommendations to improve diagnosis of ATTR amyloidosis with polyneuropathy

Amyloid transthyretin (ATTR) amyloidosis with polyneuropathy (PN) is a progressive, debilitating, systemic disease wherein transthyretin protein misfolds to form amyloid, which is deposited in the endoneurium. ATTR amyloidosis with PN is the most serious hereditary polyneuropathy of adult onset. It arises from a hereditary mutation in the TTR gene and may involve the heart as well as other organs. It is critical to identify and diagnose the disease earlier because treatments are available to help slow the progression of neuropathy. Early diagnosis is complicated, however, because presentation may vary and family history is not always known. Symptoms may be mistakenly attributed to other diseases such as chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), idiopathic axonal polyneuropathy, lumbar spinal stenosis, and, more rarely, diabetic neuropathy and AL amyloidosis. In endemic countries (e.g., Portugal, Japan, Sweden, Brazil), ATTR amyloidosis with PN should be suspected in any patient who has length-dependent small-fiber PN with autonomic dysfunction and a family history of ATTR amyloidosis, unexplained weight loss, heart rhythm disorders, vitreous opacities, or renal abnormalities. In nonendemic countries, the disease may present as idiopathic rapidly progressive sensory motor axonal neuropathy or atypical CIDP with any of the above symptoms or with bilateral carpal tunnel syndrome, gait disorders, or cardiac hypertrophy. Diagnosis should include DNA testing, biopsy, and amyloid typing. Patients should be followed up every 6–12 months, depending on the severity of the disease and response to therapy. This review outlines detailed recommendations to improve the diagnosis of ATTR amyloidosis with PN.

Analysis of autonomic outcomes in APOLLO, a phase III trial of the RNAi therapeutic patisiran in patients with hereditary transthyretin-mediated amyloidosis

Hereditary transthyretin-mediated (hATTR) amyloidosis is a progressive, debilitating disease often resulting in early-onset, life-impacting autonomic dysfunction. The effect of the RNAi therapeutic, patisiran, on autonomic neuropathy manifestations in patients with hATTR amyloidosis with polyneuropathy in the phase III APOLLO study is reported. Patients received patisiran 0.3 mg/kg intravenously (n = 148) or placebo (n = 77) once every 3 weeks for 18 months. Patisiran halted or reversed polyneuropathy and improved quality of life from baseline in the majority of patients. At baseline, patients in APOLLO had notable autonomic impairment, as demonstrated by the Composite Autonomic Symptom Score-31 (COMPASS-31) questionnaire and Norfolk Quality of Life-Diabetic Neuropathy (Norfolk QOL-DN) questionnaire autonomic neuropathy domain. At 18 months, patisiran improved autonomic neuropathy symptoms compared with placebo [COMPASS-31, least squares (LS) mean difference, − 7.5; 95% CI: − 11.9, − 3.2; Norfolk QOL-DN autonomic neuropathy domain, LS mean difference, − 1.1; − 1.8, − 0.5], nutritional status (modified body mass index, LS mean difference, 115.7; − 82.4, 149.0), and vasomotor function (postural blood pressure, LS mean difference, − 0.3; − 0.5, − 0.1). Patisiran treatment also led to improvement from baseline at 18 months for COMPASS-31 (LS mean change from baseline, − 5.3; 95% CI: − 7.9, − 2.7) and individual domains, orthostatic intolerance (− 4.6; − 6.3, − 2.9) and gastrointestinal symptoms (− 0.8; − 1.5, − 0.2). Rapid worsening of all study measures was observed with placebo, while patisiran treatment resulted in stable or improved scores compared with baseline. Patisiran demonstrates benefit across a range of burdensome autonomic neuropathy manifestations that deteriorate rapidly without early and continued treatment.

Assessment of patients with hereditary transthyretin amyloidosis - understanding the impact of management and disease progression

Timely diagnosis of hereditary variant transthyretin (ATTRv) amyloidosis is critical for appropriate treatment and optimal outcomes. Significant differences are seen between patients receiving treatment and those who are not, though disease progression may continue despite treatment in some patients. Healthcare professionals caring for patients with ATTRv amyloidosis therefore need reliable ongoing assessments to understand the continuing course of disease and make appropriate treatment choices on an individual basis. Various signs and symptoms experienced by patients may be evaluated as indicators of disease progression, though there is currently no validated score that can be used for such ongoing assessment. Recognizing this situation, a group of clinicians highly experienced in ATTR amyloidosis developed an approach to understand and define disease progression in diagnosed and treated patients with ATTRv amyloidosis. The suggested approach is based on the recognition of distinct phenotypes which may usefully inform the particular tools, tests and investigations that are most likely to be appropriate for individual patients. It is aimed at implementing appropriate and ongoing assessment of patients being treated for ATTRv amyloidosis, such that the effectiveness of management can be usefully assessed throughout the course of disease and management can be tailored according to the patient's requirements.

Personalized Medicine Implementation with Non-traditional Data Sources: A Conceptual Framework and Survey of the Literature

OBJECTIVES

With the explosive growth in availability of health data captured using non-traditional sources, the goal for this work was to evaluate the current biomedical literature on theory- driven studies investigating approaches that leverage non- traditional data in personalized medicine applications.

METHODS

We conducted a literature assessment guided by the personalized medicine unsolicited health information (pUHl) conceptual framework incorporating diffusion of innovations and task-technology fit theories.

RESULTS

The assessment provided an oveiview of the current literature and highlighted areas for future research. In particular, there is a need for: more research on the relationship between attributes of innovation and of societal structure on adoption; new study designs to enable flexible communication channels; more work to create and study approaches in healthcare settings; and more theory-driven studies with data-driven interventions.

CONCLUSION

This work introduces to an informatics audience an elaboration on personalized medicine implementation with non-traditional data sources by blending it with the pUHl conceptual framework to help explain adoption. We highlight areas to pursue future theory-driven research on personalized medicine applications that leverage non-traditional data sources.

Trial design and rationale for APOLLO, a Phase 3, placebo-controlled study of patisiran in patients with hereditary ATTR amyloidosis with polyneuropathy

BACKGROUND

Patisiran is an investigational RNA interference (RNAi) therapeutic in development for the treatment of hereditary ATTR (hATTR) amyloidosis, a progressive disease associated with significant disability, morbidity, and mortality.

METHODS

Here we describe the rationale and design of the Phase 3 APOLLO study, a randomized, double-blind, placebo-controlled, global study to evaluate the efficacy and safety of patisiran in patients with hATTR amyloidosis with polyneuropathy. Eligible patients are 18-85 years old with hATTR amyloidosis, investigator-estimated survival of ≥2 years, Neuropathy Impairment Score (NIS) of 5-130, and polyneuropathy disability score ≤IIIb. Patients are randomized 2:1 to receive either intravenous patisiran 0.3 mg/kg or placebo once every 3 weeks. The primary objective is to determine the efficacy of patisiran at 18 months based on the difference in the change in modified NIS+7 (a composite measure of motor strength, sensation, reflexes, nerve conduction, and autonomic function) between the patisiran and placebo groups. Secondary objectives are to evaluate the effect of patisiran on Norfolk-Diabetic Neuropathy quality of life questionnaire score, nutritional status (as evaluated by modified body mass index), motor function (as measured by NIS-weakness and timed 10-m walk test), and autonomic symptoms (as measured by the Composite Autonomic Symptom Score-31 questionnaire). Exploratory objectives include assessment of cardiac function and pathologic evaluation to assess nerve fiber innervation and amyloid burden. Safety of patisiran will be assessed throughout the study.

DISCUSSION

APOLLO represents the largest randomized, Phase 3 study to date in patients with hATTR amyloidosis, with endpoints that capture the multisystemic nature of this disease.

TRIAL REGISTRATION

This trial is registered at clinicaltrials.gov ( NCT01960348 ); October 9, 2013.

Content validity of symptom-based measures for diabetic, chemotherapy, and HIV peripheral neuropathy

INTRODUCTION

No treatments for axonal peripheral neuropathy are approved by the United States Food and Drug Administration (FDA). Although patient- and clinician-reported outcomes are central to evaluating neuropathy symptoms, they can be difficult to assess accurately. The inability to identify efficacious treatments for peripheral neuropathies could be due to invalid or inadequate outcome measures.

METHODS

This systematic review examined the content validity of symptom-based measures of diabetic peripheral neuropathy, HIV neuropathy, and chemotherapy-induced peripheral neuropathy.

RESULTS

Use of all FDA-recommended methods to establish content validity was only reported for 2 of 18 measures. Multiple sensory and motor symptoms were included in measures for all 3 conditions; these included numbness, tingling, pain, allodynia, difficulty walking, and cramping. Autonomic symptoms were less frequently included.

CONCLUSIONS

Given significant overlap in symptoms between neuropathy etiologies, a measure with content validity for multiple neuropathies with supplemental disease-specific modules could be of great value in the development of disease-modifying treatments for peripheral neuropathies. Muscle Nerve 55: 366-372, 2017.

Outcome measures in neuromuscular disease: is the world still flat?

Valid, responsive, and meaningful outcome measures for the measurement of the impairment, activity limitations, and quality of life in patients with neuromuscular disease are crucial to identify the natural history of disease and benefits of therapy in clinical practice and trials. Although understanding of many aspects of neuromuscular diseases has advanced dramatically, the development of outcome measures has received less attention. The scales developed from Rasch theory by the PeriNomS Group represent the biggest significant shift in thought in neuromuscular outcome measures for decades. There remain problems with many of them, and further developments are required. However, incorporating them into our outcome sets for daily use and in clinical trials will lead to the more efficient capture of meaningful change and will result in better assessment of individuals and groups of patients in both clinical trials and neurological practice.

TTR kinetic stabilizers and TTR gene silencing: a new era in therapy for familial amyloidotic polyneuropathies

INTRODUCTION

Transthyretin Familial Amyloid Polyneuropathy (TTR-FAP) is a rare disease with autosomal dominant transmission due to a point mutation of the TTR gene. By removing the main source of systemic mutant TTR, liver transplantation (LT) has become the reference therapy of this severe and fatal polyneuropathy of adult-onset, stopping disease progression in subgroup of patients. Recently, new therapeutic strategies have emerged, which intend to stabilize TTR or to silence the TTR gene. Amongst them, the TTR kinetic stabilizer tafamidis is the first drug approved in the EU.

AREAS COVERED

We shall review the natural history of TTR-FAP and the best indications for LT. Data on the efficacy, safety and tolerability of the TTR kinetic stabilizers, tafamidis and diflunisal, have been reviewed, from the pivotal Phase III clinical trials published in PubMed medical journals or presented at international meetings. We will review the ongoing phase III clinical trials of TTR gene silencing with RNAi therapeutics and ASO published in clinicaltrialgov.

EXPERT OPINION

Due to the data on efficacy, tolerability, safety, tafamidis and diflunisal became the first line anti-amyloid treatment in stage 1 TTR-FAP. Both drugs slow progression of the disease. Only tafamidis got marketing authorization. We are waiting for results of the 2 phase III clinical trials of TTR gene silencing in varied stages of the disease.