Birtamimab plus standard of care in light-chain amyloidosis: the phase 3 randomized placebo-controlled VITAL trial.

Amyloid light-chain (AL) amyloidosis is a rare, typically fatal disease characterized by the accumulation of misfolded immunoglobulin light chains (LCs). Birtamimab is an investigational humanized monoclonal antibody designed to neutralize toxic LC aggregates and deplete insoluble organ-deposited amyloid via macrophage-induced phagocytosis. VITAL was a phase 3 randomized, double-blind, placebo-controlled clinical trial assessing the efficacy and safety of birtamimab + standard of care (SOC) in 260 newly diagnosed, treatment-naive patients with AL amyloidosis. Patients received 24 mg/kg IV birtamimab + SOC or placebo + SOC every 28 days. The primary composite end point was the time to all-cause mortality (ACM) or centrally adjudicated cardiac hospitalization ≥91 days after the first study drug infusion. The trial was terminated early after an interim futility analysis; there was no significant difference in the primary composite end point (hazard ratio [HR], 0.826; 95% confidence interval [CI], 0.574-1.189; log-rank P = .303). A post hoc analysis of patients with Mayo stage IV AL amyloidosis, those at the highest risk of early mortality, showed significant improvement in the time to ACM with birtamimab at month 9 (HR, 0.413; 95% CI, 0.191-0.895; log-rank P = .021). At month 9, 74% of patients with Mayo stage IV AL amyloidosis treated with birtamimab and 49% of those given placebo survived. Overall, the rates of treatment-emergent adverse events (TEAEs) and serious TEAEs were generally similar between treatment arms. A confirmatory phase 3 randomized, double-blind, placebo-controlled clinical trial of birtamimab in patients with Mayo stage IV AL amyloidosis (AFFIRM-AL; NCT04973137) is currently enrolling. The VITAL trial was registered at www.clinicaltrials.gov as #NCT02312206.

mNIS+7 and lower limb function in inotersen treatment of hereditary transthyretin-mediated amyloidosis.

INTRODUCTION: Inotersen, an antisense oligonucleotide inhibitor of transthyretin (TTR) protein production, demonstrated significant benefit versus placebo in the modified Neuropathy Impairment Score (NIS) +7 neurophysiologic tests (mNIS+7) in patients with hereditary TTR-mediated amyloidosis (hATTR) with polyneuropathy. This analysis assessed the mNIS+7 components by anatomic location and the lower limb function (LLF) test. METHODS: Adults with hATTR in the NEURO-TTR trial (NCT01737398) were randomly assigned to receive weekly doses of subcutaneous inotersen 300 mg or placebo for 65 weeks. The mNIS+7 and LLF were assessed at 35 and 66 weeks. RESULTS: All major mNIS+7 components (muscle weakness, muscle stretch reflexes, sensation) and the LLF showed significant efficacy in patients receiving inotersen versus placebo; however, NIS-reflexes (upper limb), touch pressure (upper and lower limbs), and heart rate during deep breathing did not show significant effects. DISCUSSION: The results of this analysis reinforce the beneficial effect of inotersen on slowing neuropathy progression in patients with hATTR polyneuropathy.

Neuropathy symptom and change: Inotersen treatment of hereditary transthyretin amyloidosis.

INTRODUCTION: Hereditary transthyretin-mediated amyloidosis (hATTR) manifests as multisystem dysfunction, including progressive polyneuropathy. Inotersen, an antisense oligonucleotide, improved the course of neuropathic impairment in patients with hATTR in the pivotal NEURO-TTR study (NCT01737398). To determine inotersen's impact on symptoms and patients' neuropathy experience, we performed a post hoc analysis of the Neuropathy Symptoms and Change (NSC) score. METHODS: Stage 1 or 2 hATTR patients were randomized to receive weekly subcutaneous inotersen or placebo for 65 weeks. NSC score was assessed at baseline and 35 and 66 weeks. RESULTS: At 66 weeks, inotersen-treated patients had symptom stabilization as compared with worsening in patients receiving placebo, based on total NSC score. There were also improvements in the subdomains of muscle weakness, sensory, pain, and autonomic symptoms, and for various individual items. DISCUSSION: Inotersen treatment stabilized neuropathy symptoms, including autonomic symptoms, in patients with hATTR according to NSC score. Thus, the NSC may be an effective measure to assess neuropathy progression and patients' neuropathy experience in clinical practice.

Burden of hereditary transthyretin amyloidosis on quality of life.

INTRODUCTION: Hereditary transthyretin (hATTR) amyloidosis is a progressive, degenerative disease, with peripheral neuropathy, cardiomyopathy, and other clinical manifestations. In this study we examine the impact of hATTR amyloidosis on quality of life (QOL). METHODS: Neuropathy-specific QOL, measured with the Norfolk QOL-Diabetic Neuropathy questionnaire, was compared between patients with hATTR amyloidosis and patients with type 2 diabetes, whereas generic QOL, measured with the 36-item Short Form Health Survey version 2 (SF-36v2), was compared between patients with hATTR amyloidosis, the general population, and patients with chronic diseases. RESULTS: Neuropathy-specific QOL for patients with hATTR amyloidosis was nearly equivalent to that of patients with type 2 diabetes with diabetic neuropathy accompanied by a history of ulceration, gangrene, or amputation. Generic QOL was worse than that seen in the general population, with physical functioning worse than that for patients with multiple sclerosis and congestive heart failure. DISCUSSION: Patients with hATTR amyloidosis show significant burden on QOL, particularly in physical functioning. Muscle Nerve 60: 169-175, 2019.

A longitudinal evaluation of health-related quality of life in patients with AL amyloidosis: associations with health outcomes over time.

Light chain (AL) amyloidosis is a rare disease associated with significant, irreversible organ dysfunction and high case fatality. An observational study was conducted to assess health-related quality of life (HRQoL) in patients treated for AL amyloidosis between 1994 and 2014 with both high dose melphalan and stem cell transplantation (HDM/SCT) or non-SCT chemotherapy regimens. The SF-36v1® Health Survey (SF-36) was administered to assess HRQoL during clinic visits. Analysis of variance was used to compare pre- and post-treatment HRQoL within each treatment group to an age- and gender-adjusted general population (GP) normative sample. Cox proportional hazard models were fit to examine associations between pre-treatment levels of HRQoL and mortality within 1 and 5 years after initiating specific treatment regimens (HDM/SCT: n = 402; non-SCT chemotherapy regimens: n = 172). Among patients who received HDM/SCT, there were significant improvements following treatment in vitality, social functioning, role-emotional and mental health. Worse pre-treatment SF-36 physical component scores were associated with a greater risk of mortality in both treatment groups and follow-up periods (P ≤ 0·005 for both). [Correction added on 20 October 2017, after first online publication: This P value has been corrected]. Using HRQoL assessments in every physician visit or treatment may provide valuable insights for treating rare conditions like AL amyloidosis.

Renal Response Criteria for Clinical Trials in Amyloid Light Chain Amyloidosis.

Immunoglobin light chain (AL) amyloidosis is a rare disease characterized by organ deposition of amyloid fibrils, most commonly in the heart and kidney. Disease heterogeneity necessitates organ-specific assessment to determine prognosis and response or progression. To facilitate development of new therapies, the Amyloidosis Forum (a public-private partnership between the US Food and Drug Administration and the nonprofit Amyloidosis Research Consortium) held a series of meetings and formed multiple working groups to identify clinical trial end points and analytic strategies. This report summarizes the recommendations of Renal Working Group. Estimated glomerular filtration rate (eGFR) and proteinuria were selected to evaluate eligibility, response, and/or progression in the context of investigational clinical trials for patients with AL amyloidosis. Accurate response assessments at the earliest possible time point were emphasized. The context of use, specific patient population, and the investigational therapeutic mechanism should ultimately drive selection of appropriate end points to evaluate renal response/progression in AL amyloidosis clinical trials.

Clinical Confirmation of Pan-Amyloid Reactivity of Radioiodinated Peptide 124I-p5+14 (AT-01) in Patients with Diverse Types of Systemic Amyloidosis Demonstrated by PET/CT Imaging.

There are at least 20 distinct types of systemic amyloidosis, all of which result in the organ-compromising accumulation of extracellular amyloid deposits. Amyloidosis is challenging to diagnose due to the heterogeneity of the clinical presentation, yet early detection is critical for favorable patient outcomes. The ability to non-invasively and quantitatively detect amyloid throughout the body, even in at-risk populations, before clinical manifestation would be invaluable. To this end, a pan-amyloid-reactive peptide, p5+14, has been developed that is capable of binding all types of amyloid. Herein, we demonstrate the ex vivo pan-amyloid reactivity of p5+14 by using peptide histochemistry on animal and human tissue sections containing various types of amyloid. Furthermore, we present clinical evidence of pan-amyloid binding using iodine-124-labeled p5+14 in a cohort of patients with eight (n = 8) different types of systemic amyloidosis. These patients underwent PET/CT imaging as part of the first-in-human Phase 1/2 clinical trial evaluating this radiotracer (NCT03678259). The uptake of 124I-p5+14 was observed in abdominothoracic organs in patients with all types of amyloidosis evaluated and was consistent with the disease distribution described in the medical record and literature reports. On the other hand, the distribution in healthy subjects was consistent with radiotracer catabolism and clearance. The early and accurate diagnosis of amyloidosis remains challenging. These data support the utility of 124I-p5+14 for the diagnosis of varied types of systemic amyloidosis by PET/CT imaging.

Cardiac Amyloid Detection by PET/CT Imaging of Iodine (124I) Evuzamitide (124I-p5+14): A Phase 1/2 Study.

BACKGROUND: The noninvasive detection of cardiac amyloid, as well as deposits in other vital organs, is critical for early diagnosis and quantitative disease monitoring. Positron emission tomography is an intrinsically quantitative imaging modality suitable for high-resolution amyloid detection. OBJECTIVES: This study sought to evaluate the safety and efficacy of a novel amyloid-reactive peptide, designated p5+14, labeled with iodine-124 (124I), in patients with diverse types of systemic amyloidosis. METHODS: In a single-site, open label phase 1/2 study (NCT03678259), the safety, biodistribution, and sensitivity of a single intravenous infusion of 124I-evuzamitide was assessed in patients with systemic amyloidosis (n = 50), asymptomatic transthyretin sequence variant carriers (n = 2), and healthy volunteers (n = 5). Subjects were administered 1.4 ± 0.2 mg of 124I-evuzamitide (71.5 ± 12.4 MBq) and positron emission tomography/x-ray computed tomography images acquired at 5.2 hours (Q25-Q75: 4.9-5.4 hours) postinfusion. Images were assessed visually and semi-quantitatively for positive uptake of radiotracer in the heart and other major organs. RESULTS: Uptake of 124I-evuzamitide in the heart and other abdominothoracic organs was consistent with the patient's clinical presentation and the type of amyloidosis. The patient- and cardiac-associated sensitivity for imaging and clinical observations was 93.6% (95% CI: 82.8%-97.8%) and 96.2% (95% CI: 81.8%-99.8%), respectively. Semi-quantitative uptake of the radiotracer correlated significantly with serum N-terminal pro-B-type natriuretic peptide measurements in patients with light chain-associated amyloidosis. Cardiac uptake was not observed in any healthy volunteers. The agent was well tolerated, with 1 drug-related adverse event and no deaths. CONCLUSIONS: 124I-evuzamitide is an amyloid-binding radiotracer capable of detecting cardiac amyloid in patients with high sensitivity.

Patient-reported burden of hereditary transthyretin amyloidosis on functioning and well-being.

BACKGROUND: Hereditary transthyretin (hATTR) amyloidosis is a rare, systemic, progressive, and life-threatening disease in which transthyretin proteins misfold and aggregate as insoluble amyloid deposits, disrupting nervous, cardiac, gastrointestinal, and other organ tissues. There are limited available data about the experience of patients living with hATTR amyloidosis. This study used a qualitative, non-interventional design to explore the humanistic burden of hATTR amyloidosis from the patient's perspective. RESULTS: Fourteen adults with hATTR amyloidosis, recruited from a patient advocacy group or an academic clinical center, participated in individual semi-structured interviews either in person or by telephone. Patients were asked to describe their experiences living with the condition, including symptoms and disease-related impacts on functioning and well-being, work, and activities of daily living (ADLs). Interviews were transcribed verbatim and analyzed for key concepts using a grounded theory approach. Patients described many symptoms of hATTR amyloidosis, particularly those associated with peripheral neuropathy such as pain, numbness, weakness, and paresthesia. Symptoms of autonomic neuropathy, such as gastrointestinal dysfunction, and symptoms related to cardiac dysfunction were also common. Worsening symptoms, especially those impacting patients' ability to walk or use their hands, often led to a loss of autonomy and an inability to work or perform ADLs. Disease-related disability also interfered with patients' participation in social activities, and contributed to feelings of fear, frustration, or sadness. CONCLUSIONS: The impacts of hATTR amyloidosis were profound for the patients interviewed for this study. They described a sense of loss as their condition progressed and impacted them physically, emotionally, and socially. Patients' reports of symptoms and impacts of hATTR amyloidosis illustrate the complex and varied manifestations of this disease. The progression of symptoms and increasing impacts of hATTR amyloidosis also highlight the need for an earlier diagnosis and effective clinical intervention to preserve patients' functioning and well-being.

The Clinical and Economic Burden of Newly Diagnosed Hereditary Transthyretin (ATTRv) Amyloidosis: A Retrospective Analysis of Claims Data.

INTRODUCTION: Little is known about the burden of hereditary transthyretin (ATTRv) amyloidosis, a genetic, progressive, and fatal disease caused by extracellular deposition of transthyretin amyloid fibrils. The study's aim was to estimate costs and disease burden associated with ATTRv amyloidosis in a real-world setting. METHODS: Using IBM® MarketScan® Commercial and Medicare Supplemental data, we identified patients at least 18 years of age with newly diagnosed ATTRv amyloidosis. Diagnosis required at least one medical claim with relevant diagnosis code (International Classification of Diseases, 9th Revision, Clinical Modification [ICD-9-CM] 277.30-.31, 277.39; ICD-10-CM E85.0-.4, E85.89, E85.9) between January 1, 2014 and December 31, 2016, and at least one additional criterion occurring during study period (2013-2017): at least 15 days diflunisal use without more than a 30-day gap; liver transplant; or claim with codes E85.1 or E85.2. First diagnosis date was study index. Continuous enrollment 1-year pre-index (baseline) and post-index (follow-up) was required. Patients with baseline amyloidosis diagnosis were excluded. Outcomes of interest were comorbidities and 1-year follow-up healthcare utilization and costs (also reported quarterly). RESULTS: Among 185 qualifying patients, mean age was 59.2 years (standard deviation 15.2), 54.1% were female, and baseline Charlson comorbidity index was 2.2 (2.5). Neuropathy (30.3%), diabetes (27.0%), and cardiovascular-related comorbidities, including dyspnea (25.9%) and congestive heart failure (21.6%), were common during follow-up. Nearly a quarter of patients (24.9%) were hospitalized during follow-up. Most hospitalizations and emergency department visits occurred in the first quarter post-diagnosis (18.9%, 17.8%, respectively) and dropped in subsequent quarters. The annual mean total cost was $64,066, with inpatient services contributing the majority of the expenses ($34,461), followed by outpatient ($23,853), and then pharmacy ($5752). As with utilization, costs were highest in the first quarter post-diagnosis and dropped in subsequent quarters. CONCLUSION: Patients newly diagnosed with ATTRv amyloidosis have substantial healthcare utilization and costs in the first year, primarily the initial months, post-diagnosis. Further research should examine later costs associated with disease progression and end-of-life care.

Inotersen preserves or improves quality of life in hereditary transthyretin amyloidosis.

OBJECTIVE: To examine the impact on quality of life (QOL) of patients with hATTR amyloidosis with polyneuropathy treated with inotersen (Tegsedi™) versus placebo. METHODS: Data were from the NEURO-TTR trial (ClinicalTrials.gov Identifier: NCT01737398), a phase 3, multinational, randomized, double-blind, placebo-controlled study of inotersen in patients with hATTR amyloidosis with polyneuropathy. At baseline and week 66, QOL measures-the Norfolk-QOL-Diabetic Neuropathy (DN) questionnaire and SF-36v2® Health Survey (SF-36v2)-were assessed. Treatment differences in mean changes in QOL from baseline to week 66 were tested using mixed-effect models with repeated measures. Responder analyses compared the percentages of patients whose QOL meaningfully improved or worsened from baseline to week 66 in inotersen and placebo arms. Descriptive analysis of item responses examined treatment differences in specific activities and functions at week 66. RESULTS: Statistically significant mean differences between treatment arms were observed for three of five Norfolk-QOL-DN domains and five of eight SF-36v2 domains, with better outcomes for inotersen than placebo in physical functioning, activities of daily living, neuropathic symptoms, pain, role limitations due to health problems, and social functioning. A larger percentage of patients in the inotersen arm than the placebo arm showed preservation or improvement in Norfolk-QOL-DN and SF-36v2 scores from baseline to week 66. Responses at week 66 showed more substantial problems with daily activities and functioning for patients in the placebo arm than in the inotersen arm. CONCLUSION: Patients with hATTR amyloidosis with polyneuropathy treated with inotersen showed preserved or improved QOL at 66 weeks compared to those who received placebo.

Epidemiology of AL amyloidosis: a real-world study using US claims data.

Amyloid light-chain (AL) amyloidosis is a rare disease caused by extracellular deposition of misfolded immunoglobulin light chains. This study aimed to provide an up-to-date estimate of prevalence and incidence of AL amyloidosis in the United States. Using claims databases from years 2007 to 2015, adults ≥18 years old with AL amyloidosis were included if they had (1) at least 1 inpatient or 2 outpatient claims consistent with AL amyloidosis and (2) received 1 AL-specific treatment. Prevalence was calculated as the number of AL patients divided by the number of enrollees on June 30th of each calendar year. Incidence was calculated as the number of patients with AL who were disease-free and enrolled with a health plan for 1 year prior, divided by the number of enrollees with enrollment from July 1st of the previous year to June 30th of each calendar year. The prevalence of AL amyloidosis increased significantly between 2007 and 2015, from 15.5 cases per million in 2007 to 40.5 in 2015, an annual percentage change (APC) of 12% (P < .001). The incidence ranged from 9.7 to 14.0 cases per million person-years (APC, 3%; P = .114) with no statistically significant increase. There was an increase in AL amyloidosis prevalence over a 9-year period coupled with stable incidence rates. Although there is no diagnosis code specific to AL amyloidosis and no validated method for identifying this condition using claims data, extrapolating from our data, there are at least 12 000 adults in the United States living with AL amyloidosis, and the number seems likely to rise.

Healthcare resource utilization and costs in amyloid light-chain amyloidosis: a real-world study using US claims data.

AIM: To estimate healthcare utilization and costs in amyloid light-chain (AL) amyloidosis. PATIENTS & METHODS: AL amyloidosis patients were identified in 2007-2015 claims databases if they had ≥1 inpatient/≥2 outpatient claims consistent with AL amyloidosis and received ≥1 AL-specific treatment. Descriptive statistics were reported. RESULTS: 50.1% (n = 3670) were admitted ≥1 time during the year, 11.3% (n = 827) ≥3 times. From 2007 to 2015, bortezomib use increased from 4.6 to 25.3%; melphalan use decreased from 18.9 to 2.0%; costs increased from 92,866 to $114,030. Among incident patients with at least 2 years of follow-up, healthcare utilization and costs decreased from first to second year post-diagnosis. CONCLUSION: AL chemotherapy-based prescribing practices changed. Total annual healthcare costs increased over time among AL amyloidosis patients.

Light Chain (AL) Amyloidosis: The Journey to Diagnosis.

BACKGROUND: Light chain (AL) amyloidosis is a rare, complex disease associated with significant morbidity and mortality. Delays in diagnosis are common and may have detrimental consequences on patients' prognosis. Too little is known regarding the patient journey to diagnosis. OBJECTIVE: The objective of this study was to describe the patient-reported journey to a correct diagnosis for AL amyloidosis. METHODS: Using a mixed-methods approach, data were collected from clinician (n = 4) and patient (n = 10) interviews and a survey of community-based patients with AL amyloidosis (n = 341). Data were used to document the patient experience between the onset of symptoms and the receipt of a diagnosis. RESULTS: Delays in diagnosis were common. Qualitative and quantitative data indicated that initial symptoms were varied and similar to other more prevalent diseases. Two themes regarding the journey to diagnosis emerged: (1) barriers to an early diagnosis; and (2) the emotional toll of the journey. Time to diagnosis was heavily influenced by how patients interpreted their initial symptoms, whether they sought early medical help, and challenges associated with making differential diagnoses. Survey results indicate that patients with primary cardiac involvement were more likely to receive a delayed diagnosis than those with primary kidney involvement. Patients described mixed emotions associated with the eventual diagnosis of AL amyloidosis. CONCLUSIONS: These data support a need for better early identification and support for patients seeking a diagnosis. Increasing clinician awareness may reduce the time to diagnosis. Additional research is needed to identify optimal diagnostic testing to reduce delays in treatment initiation and subsequent severe impacts on health.

Treatment Tolerability in Patients with Immunoglobulin Light-Chain Amyloidosis.

BACKGROUND: Immunoglobulin light-chain amyloidosis (AL amyloidosis) is a rare and often fatal disease for which there is currently no treatment approved by the US Food and Drug Administration or the European Medicines Agency. Treatment options, which are typically based on therapies for multiple myeloma and are used off-label, are associated with substantial adverse events (AEs). Because the severity of AEs is often determined by clinicians, evaluations of treatment tolerability may not fully consider patients' own experience with treatment. OBJECTIVES: To explore the prevalence of AEs and treatment tolerability problems as reported by patients who received therapies for AL amyloidosis, and to examine the effects of AEs on treatment continuation and on health-related quality of life (HRQOL). METHODS: Patients with AL amyloidosis were recruited for this noninterventional, longitudinal, online survey. The patients responded to survey items regarding demographics, disease characteristics, most recent AL amyloidosis treatment, and HRQOL. The study analyses are based on data collected during the 6-month follow-up survey and are restricted to patients who completed the baseline and 6-month surveys and received treatment for AL amyloidosis within 6 months before the follow-up survey. RESULTS: A total of 100 patients met the inclusion criteria and were included in the study. The patients self-reported having a variety of AEs, which ranged in severity. Overall, 69.4% of patients had problems tolerating their treatment in the past 6 months, of whom 22% discontinued at least 1 therapy. In addition, approximately 33% of patients reduced their AL amyloidosis treatment because of AEs. Most often reported AEs included fatigue (83%), shortness of breath (53%), nausea (52%), and diarrhea (51%). Overall, 50% of the patients reported that their treatment was moderately well-tolerated and 41% said it was very well-tolerated. Those whose treatment was not well-tolerated had significantly worse HRQOL than patients whose treatment was well-tolerated. CONCLUSIONS: Patient-reported experiences should be considered by clinicians when making treatment-related decisions. More research is needed to explore additional factors that may contribute to treatment discontinuation in patients with AL amyloidosis.

The burden of amyloid light chain amyloidosis on health-related quality of life.

BACKGROUND: Light chain (AL) amyloidosis is a rare disease characterized by misfolded amyloid protein deposits in tissues and vital organs, and little is known about the burden of AL amyloidosis on health-related quality of life. This study aimed to quantify the burden of AL amyloidosis in terms of health-related quality of life in a diverse, community-based sample of AL amyloidosis patients. RESULTS: The SF-36v2® Health Survey (SF-36v2), a widely used generic measure of health-related quality of life (using physical and mental summary scales and subscales assessing eight aspects of functioning and well-being), was administered as an online survey of AL amyloidosis patients with AL amyloidosis (ClinicalTrials.gov, NCT02574676 ; n = 341). Compared with adjusted general population sample norms, health-related quality of life of AL amyloidosis patients was significantly worse across all SF-36v2 scales and summary measures based on analysis of variance (p < 0.05 for all). The largest decrement in AL amyloidosis patients was related to General Health (Δ = 9.7; p < 0.001). With the exception of Bodily Pain and Mental Health, differences were also clinically meaningful based on established clinically minimal important differences. The burden of AL amyloidosis overall and in key subgroups tended to be greater on physical health than on mental health. Stratified analyses indicated additional burden among patients with recently diagnosed disease and those with cardiac involvement than among their respective counterparts. CONCLUSION: Understanding the burden of AL amyloidosis highlights the unmet need for treatment, helps physicians identify ancillary treatments and services geared towards improving patients' functioning, well-being, and overall health-related quality of life. These findings also help to support the use of health-related quality of life end points as important outcome measures in current and future treatment studies. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02574676 . Registered October 5, 2015.

Psychometric validation of the SF-36 Health Survey in light chain amyloidosis: results from community-based and clinic-based samples.

BACKGROUND: Light chain (AL) amyloidosis, a rare and life-threatening protein misfolding disorder, causes organ damage and severely impacts health-related quality of life (HRQoL). No patient-reported outcome (PRO) HRQoL measure has been validated for use in an AL amyloidosis patient population, leaving a gap for researchers conducting observational studies and clinical trials for drug development. The SF-36 Health Survey (SF-36) has been the most frequently used PRO in AL amyloidosis studies to date, and early qualitative validation studies support its use in this population. The aim of this study was to assess the psychometric properties of the SF-36 among patients with AL amyloidosis. METHODS: Data from community-based (n=341) and clinic-based (n=1,438) observational studies were used to document the psychometric properties of the SF-36 in this disease population. Reliability was estimated using internal consistency (Cronbach's alpha) and test-retest reliability (intraclass correlation). Convergent validity, known-groups validity, and the ability to detect change were assessed with available criterion variables. RESULTS: Scale reliability (Cronbach's alpha ≥0.780 for all scores) and test-retest reliability (intraclass correlation coefficients ≥0.731 for all) were acceptable. Scale convergent validity was supported by strong correlations with conceptually related measures. Mean SF-36 scores varied by response to treatment (P<0.05 for all scores) and a self-reported measure of disease severity (P<0.001 for all scores). Data indicate that the SF-36 is sensitive to changes in other measures over time. CONCLUSION: This study provided clear and consistent evidence of the psychometric properties of the SF-36 in both community-based and clinic-based samples of patients with AL amyloidosis.

Content validation of the SF-36v2® health survey with AL amyloidosis patients.

BACKGROUND: This study examined the content validity of the SF-36v2® Health Survey (SF-36v2) in patients with AL amyloidosis using qualitative interviews with physicians and patients. The study included three distinct phases of qualitative research: concept elicitation interviews among physicians, concept elicitation interviews among patients, and cognitive debriefing interviews among patients. The concept elicitation interviews focused on areas of health-related quality of life that are affected by AL amyloidosis and may be affected by treatment, while patient cognitive debriefings aimed to confirm whether the SF-36v2 instructions, recall period, items, and response choices were comprehensive and understandable to AL amyloidosis patients. RESULTS: Physicians discussed the importance of measuring physical functioning, general health, mental/emotional health, sleep, fatigue, and work impact; though they also reported that they do not routinely use a standard Patient-Reported Outcome (PRO) measure of health-related quality of life. Patients described social, physical, role, and emotional impacts of AL amyloidosis and various treatments. Cognitive debriefing interviews confirmed the relevance of the concepts measured by the SF-36v2 and indicated that patients found the SF-36v2 both easy to understand and complete, that the SF-36v2 instructions and items were comprehensive and understandable without change, and the response choices and recall period were appropriate for use with patients with AL amyloidosis. CONCLUSIONS: The findings support the content validity of the SF-36v2 as an appropriate measure of health-related quality of life in patients with AL amyloidosis.