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Background: Hereditary transthyretin amyloidosis (ATTRv) is a fatal disease that affects multiple organs. Up to 30% of patients with ATTRv also experience renal complications, including proteinuria and a decline in eGFR. Recently, new treatments for ATTRv, a tetramer stabiliser and transthyretin small interfering RNA (TTR siRNA) therapeutics, have emerged. However, the effectiveness of these new treatments on renal complications in ATTRv remains unknown., Methods: We retrospectively collected clinical data from ATTRv patients and analysed the relationship between the initial renal complications and age. We also examined whether the new treatments affected the clinical course of renal symptoms, using eGFR changes or longitudinal data on urine protein/albumin creatinine ratio., Results: A total of 16 patients' data were collected. Regarding their initial renal complications, we found that patients with proteinuria had an earlier age at onset than those with a decline in eGFR. Notably, longitudinal data showed that TTR siRNA therapeutics reduced proteinuria and increased serum protein, while none of the new treatments could demonstrate a significant improvement in the slope of eGFR decline., Conclusions: We demonstrated that TTR siRNA therapeutics represent potential candidates for ATTRv nephropathy, despite the fact that their use has been limited to neurological symptoms to date.

Background: Tafamidis emerged as the first FDA-approved drug for treating termed amyloid fibrils. This study aims to analyze adverse events (AEs) related to tafamidis from the second quarter (Q2) of 2019 to the fourth quarter (Q4) of 2023 from the FDA adverse event reporting system (FAERS) database., Research Design and Methods: The AE data related to tafamidis from 2019 Q2 to 2023 Q4 were collected and standardized. Various signal quantification techniques, including reporting odds ratio (ROR), proportional reporting ratio (PRR), Bayesian confidence propagation neural network, and multi-item gamma Poisson shrinker, were employed for analysis., Results: Among the 8742 AE reports with tafamidis as the primary suspected drug, 180 preferred terms of AEs spanning 27 different system organ classes were identified. Unique adverse events to tafamidis included renal and urinary disorders and ear and labyrinth disorders, with not mentioned in the official drug label. Additionally, uncommon but significantly strong AE signals, such as blood culture positive and acquired hemophilia, were observed. Common AEs with relatively high occurrence rates included death, off-label use, fall, hypoacusis, and dysphagia., Conclusion: These findings offer valuable insights for optimizing the use of tafamidis and reducing potential side effects, thereby facilitating its safe use in clinical settings.

Aims: Transthyretin amyloid cardiomyopathy (ATTR-CM) is a progressive disease that causes heart failure due to amyloid fibril deposition. Tafamidis was approved as the first causal treatment in 2020. We here report on real-world data in patients treated with tafamidis for at least 12 months according to the recently defined European Society for Cardiology (ESC) consensus criteria for disease progression., Methods and Results: Three hundred and eight wildtype and 31 hereditary ATTR-CM patients were prospectively enrolled after first diagnosis of ATTR-CM and initiation of tafamidis 61 mg once daily treatment. After 12 months, significant deterioration in Karnofsky Index, estimated glomerular filtration rate (eGFR), N-terminal brain natriuretic peptide (NT-proBNP), septum thickness and left ventricular ejection fraction (LVEF) could be observed, significant disease progression was only detected in 25 patients (9%) using ESC consensus criteria. Mean survival time was 37 months with no differences between responders and non-responders. NT-proBNP was the only independent predictor for poor therapy response ( p  = .008)., Conclusions: The majority of patients showed no significant disease progression according to the ESC consensus criteria after 12 months of therapy with tafamidis. However, at 12 months, treatment response based on the ESC consensus criteria was not associated with improved survival. Moreover, higher levels of NT-proBNP at diagnosis of ATTR-CM appears to predict poorer treatment response, confirming that timely initiation of therapy is advantageous.

Aims: Novel ribonucleic acid interference (RNAi) therapeutics such as patisiran and inotersen have been shown to benefit neurologic disease course and quality of life in patients with hereditary transthyretin amyloidosis (ATTRv). We aimed to determine the impact of RNAi therapeutics on myocardial amyloid load using quantitative single photon emission computed tomography/computed tomography (SPECT/CT) imaging in patients with ATTRv-related cardiomyopathy (ATTRv-CM). We furthermore compared them with wild-type ATTR-CM (ATTRwt-CM) patients treated with tafamidis. Methods and results: ATTRv-CM patients underwent [ 99m Tc]-radiolabeled diphosphono-1,2-propanodicarboxylic acid ( 99m Tc-DPD) scintigraphy and quantitative SPECT/CT imaging before and after 12 months (IQR: 11.0-12.0) of treatment with RNAi therapeutics (patisiran: n  = 5, inotersen: n  = 4). RNAi treatment significantly reduced quantitative myocardial uptake as measured by standardised uptake value (SUV) retention index (baseline: 5.09 g/mL vs. follow-up: 3.19 g/mL, p  = .028) in ATTRv-CM patients without significant improvement in cardiac function. Tafamidis treatment resulted in a significant reduction in SUV retention index (4.96 g/mL vs. 3.27 g/mL, p  < .001) in ATTRwt-CM patients (historical control cohort: n  = 40) at follow-up [9.0 months (IQR: 7.0-10.0)] without beneficial impact on cardiac function. Conclusions: RNAi therapeutics significantly reduce quantitative myocardial uptake in ATTRv-CM patients, comparable to tafamidis treatment in ATTRwt-CM patients, without impact on cardiac function. Serial 99m Tc-DPD SPECT/CT imaging may be a valuable tool to quantify and monitor response to disease-specific therapies in both ATTRv-CM and ATTRwt-CM.

Background: In 2019, 2020 and 2022, the Japanese Government approved the use of tafamidis and two technetium-scintigraphies for transthyretin amyloid (ATTR) cardiomyopathy, and announced the patient criteria for tafamidis therapy. In 2018, we had started a nation-wide pathology consultation of amyloidosis., Objective: To reveal the impact of approval of tafamidis and technetium-scintigraphy on the diagnosis of ATTR cardiomyopathy., Methods: Ten institutes participated in this study on the pathology consultation of amyloidosis and shared rabbit polyclonal anti-κ 116-133 , anti-λ 118-134 , and anti-transthyretin 115-124 antibodies. Proteomic analysis was performed when the typing diagnosis by immunohistochemistry was unavailable., Results: Out of 5400 consultation cases received from April 2018 to July 2022, the type of amyloidosis by immunohistochemistry was determined in 4119 of the 4420 Congo-red positive cases. The incidences of AA, ALκ, ALλ, ATTR, Aβ2M and others were 3.2, 11.3, 28.3, 54.9, 0.6 and 1.8%, respectively. Out of 2208 cardiac biopsy cases received, 1503 cases were ATTR positive. There were 4.0 and 4.9 times more total cases and ATTR-positive cases, respectively, in the last 12 months as compared to the first 12 months., Conclusions: The approval of tafamidis and technetium-scintigraphy raised the awareness of ATTR cardiomyopathy, leading to an upsurge in ATTR-positive cardiac biopsy cases.

Background: Hereditary transthyretin (TTR) amyloidosis (ATTRv) initially presents as a polyneuropathy and/or a cardiomyopathy. Central nervous system (CNS) pathology in ATTRv amyloidosis, including focal neurological episodes, dementia, cerebrovascular bleeding, and seizures, appears around a decade later. Wild-type (WT) TTR amyloidosis (ATTRwt) causes a cardiomyopathy. CNS pathology risk likely also increases in these patients as cardiomyopathy progresses. Herein, we study tafamidis-mediated TTR kinetic stabilisation in cerebrospinal fluid (CSF)., Methods: Varying tafamidis concentrations (50-1000 nM) were added to CSF from healthy donors or ATTRv patients, and TTR stabilisation was measured via the decrease in dissociation rate., Results: Tafamidis meglumine (Vyndaqel) can be dosed at 20 or 80 mg QD. The latter dose is bioequivalent to a 61 mg QD dose of tafamidis free acid (Vyndamax). The tafamidis CSF concentration in ATTRv patients on 20 mg Vyndaqel is ∼125 nM. By linear extrapolation, we expect a CSF concentration of ∼500 nM at the higher dose. When tafamidis is added to healthy donor CSF at 125 or 500 nM, the WT TTR dissociation rate decreases by 42% or 87%, respectively., Conclusions: Tafamidis stabilises TTR in CSF to what is likely a clinically meaningful extent at CSF concentrations achieved by the normal tafamidis dosing regimen.

Background: By stabilizing transthyretin, tafamidis delays progression of amyloidosis due to transthyretin variant (ATTRv) and replaced liver transplantation (LT) as the first-line therapy. No study compared these two therapeutic strategies., Methods: In a monocentric retrospective cohort analysis, patients with ATTRv amyloidosis treated with either tafamidis or LT were compared using a propensity score and a competing risk analysis for three endpoints: all-cause mortality, cardiac worsening (heart failure or cardiovascular death) and neurological worsening (worsening in PolyNeuropathy Disability score)., Results: 345 patients treated with tafamidis ( n  = 129) or LT ( n  = 216) were analyzed, and 144 patients were matched (72 patients in each group, median age 54 years, 60% carrying the V30M mutation, 81% of stage I, 69% with cardiac involvement, median follow-up: 68 months). Patients treated with tafamidis had longer survival than LT patients (HR: 0.35; p  = .032). Conversely, they also presented a 3.0-fold higher risk of cardiac worsening and a 7.1-fold higher risk of neurological worsening ( p  = .0071 and p <  .0001 respectively)., Conclusions: ATTRv amyloidosis patients treated with tafamidis would present a better survival but also a faster deterioration of their cardiac and neurological statuses as compared with LT. Further studies are needed to clarify the therapeutic strategy in ATTRv amyloidosis.

Background: Tafamidis inhibits progression of transthyretin (TTR) amyloid cardiomyopathy (ATTR-CM) by binding TTR tetramer and inhibiting dissociation to monomers capable of denaturation and deposition in cardiac tissue. While the phase 3 ATTR-ACT trial demonstrated the efficacy of tafamidis, the degree to which the approved dose captures the full potential of the mechanism has yet to be assessed., Methods: We developed a model of dynamic TTR concentrations in plasma to relate TTR occupancy by tafamidis to TTR stabilisation. We then developed population pharmacokinetic-pharmacodynamic models to characterise the relationship between stabilisation and measures of disease progression., Results: Modelling individual patient data of tafamidis exposure and increased plasma TTR confirmed that single-site binding provides complete tetramer stabilisation in vivo . The approved dose was estimated to reduce unbound TTR tetramer by 92%, and was associated with 53%, 56% and 49% decreases in the rate of change in NT-proBNP, KCCQ-OS, and six-minute walk test disease progression measures, respectively. Simulating complete TTR stabilisation predicted slightly greater reductions of 58%, 61% and 54%, respectively., Conclusions: These findings support the value of TTR stabilisation as a clinically beneficial treatment option in ATTR-CM and the ability of tafamidis to realise nearly the full therapeutic benefit of this mechanism., Clinicaltrials.gov Identifier: NCT01994889.

Background: A recently published expert consensus document recommended a multiparametric tool to monitor cardiac disease progression in patients with transthyretin cardiac amyloidosis (ATTR-CA). We aimed to evaluate the effect of the transthyretin stabiliser drug, tafamidis, by applying this integrative tool., Methods: We retrospectively applied a multiparametric tool in a group of ATTR-CA patients who were given tafamidis between the years 2019-2021 and were followed in a dedicated clinic. We used three pre-specified follow-up timepoints: at 6, 12 and 18 months., Results: We included 16 ATTR-CA patients (wild-type ( n  = 14) and mutant ( n  = 2)). The median age at the initiation of tafamidis was 76 (IQR 70, 84) years and 75% of study patients were classified as NYHA functional class 2 or 3. All patients had elevated levels of high-sensitive troponin T (median 92 (IQR 63, 115) ng/L) and NT-proBNP (median 3784 (2290, 8773) pg/mL). At the end of 18-month follow-up, two patients have suffered from high-grade atrioventricular block and required permanent pacing, and one patient had heart-failure-related admission. Twenty-five percent and 50% of patients were classified as NYHA Class 1 at the initiation of tafamidis and at 18-months treatment, respectively. No patient was defined with disease progression at 6- or 12-month follow up; however, one patient (14%) was defined with a deteriorated disease status at 18-month follow-up., Conclusions: Based on a multiparametric tool, the use of tafamidis promoted disease stabilisation in the majority of patients at 18-month follow-up. Further study should focus on monitoring disease improvement in patients with ATTR-CA.

Background: TTR aggregation causes hereditary transthyretin (TTR) polyneuropathy (ATTRv-PN) in individuals with destabilised TTR variants. ATTRv-PN can be treated with ligands that bind TTR and prevent aggregation. One such ligand, tafamidis, is widely approved to treat ATTRv-PN. We explore how TTR stabilisation markers relate to clinical efficacy in 210 ATTRv-PN patients taking tafamidis., Methods: TTR concentration in patient plasma was measured before and after tafamidis treatment using assays for native or combined native + non-native TTR. TTR tetramer dissociation kinetics, which are slowed by tafamidis binding, were also measured., Results: Native TTR levels increased by 56.8% while combined native + non-native TTR levels increased by 3.1% after 24 months of tafamidis treatment, implying that non-native TTR decreased. Accordingly, the fraction of native TTR increased from 0.54 to 0.71 with tafamidis administration. Changes in native and non-native TTR levels were uncorrelated with clinical response to tafamidis. TTR tetramer dissociation generally slowed to an extent consistent with ∼40% of TTR being tafamidis-bound. Male non-responders had a lower extent of binding., Conclusions: Native and non-native TTR concentration changes cannot be used as surrogate measures for therapeutic efficacy. Also, successful tafamidis therapy requires only moderate TTR stabilisation. Male patients may benefit from higher tafamidis doses.

Aims: The impact of tafamidis on myocardial strain in patients with transthyretin amyloid cardiomyopathy (ATTR-CM) have been barely investigated. We aimed to determine tafamidis-induced changes using serial speckle tracking echocardiography and to identify imaging parameters for specific therapy monitoring., Methods and Results: ATTR-CM patients underwent serial TTE with two-dimensional (2 D) speckle tracking imaging. Patients receiving tafamidis free acid 61 mg ( n  = 62) or tafamidis meglumine 20 mg ( n  = 21) once daily (QD) showed stable measurements at follow-up (61 mg: 8.5 months, 20 mg: 7.0 months) in LV global longitudinal strain (GLS) (61 mg: -11.75% vs. -11.58%, p  = 0.534; 20 mg: -10.61% vs. -10.12%, p  = 0.309), right ventricular (RV) GLS (61 mg: -14.18% vs. -13.72%, p  = 0.377; 20 mg: -14.53% vs. -13.99%, p  = 0.452) and left atrial (LA) reservoir strain (LASr; 61 mg: 8.80% vs. 9.42%, p  = 0.283; 20 mg: 8.23% vs. 8.67%, p  = 0.589), whereas treatment-naïve ATTR-CM patients ( n  = 54) had clear signs of disease progression at the end of the observation period (10.5 months; LV-GLS: -11.71% vs. -10.59%, p  = 0.001; RV-GLS: -14.36% vs. -12.99%, p  = 0.038; LASr: 10.67% vs. 8.41%, p  = 0.005). Between-group comparison at follow-up revealed beneficial effects of tafamidis free acid 61 mg on LASr ( p  = 0.003) and the LV (LV-GLS: p  = 0.030, interventricular septum (IVS): p  = 0.006), resulting in clinical benefits (six-minute walk distance (6-MWD): p  = 0.006, NT-proBNP: p= <0.001), while patients treated with tafamidis meglumine 20 mg QD showed positive effects on LASr ( p  = 0.039), but no differences with respect to the LV (LV-GLS: p  = 0.274, IVS: p  = 0.068) and clinical status (6-MWD: p  = 0.124, NT-proBNP: p  = 0.053) compared to the natural course., Conclusions: Treatment with tafamidis free acid 61 mg in ATTR-CM patients delays the deterioration of LA and LV longitudinal function, resulting in significant clinical benefits compared with natural history. Serial TTE with 2 D speckle tracking imaging may be appropriate for disease-specific therapy monitoring.

What Is This Plain Language Summary About?: This summary presents the results from an ongoing, long-term extension study that followed an earlier study called ATTR-ACT. People who took part in this extension study and ATTR-ACT have a type of heart disease known as transthyretin amyloid cardiomyopathy (ATTR-CM for short), which causes heart failure and death. In ATTR-ACT, people took either a medicine called tafamidis or a placebo (a pill that looks like the study drug but does not contain any active ingredients) for up to 2½ years. So far, in the long-term extension study, people have continued taking tafamidis, or switched from taking a placebo to tafamidis, for another 2½ years. Researchers looked at how many people died in ATTR-ACT and the extension study. The long-term extension study is expected to end in 2027, so these are interim (not final) results., What Did Researchers Find Out?: In the extension study of ATTR-ACT, the risk of dying was lower in people who took tafamidis continuously throughout ATTR-ACT and the extension study than in people who took placebo in ATTR-ACT and switched to tafamidis in the extension study., What Do the Results Mean?: Taking tafamidis increases how long people with ATTR-CM live. People with ATTR-CM who take tafamidis early and continuously are more likely to live longer than those who do not. These results highlight the importance of early detection and treatment in people with ATTR-CM. Clinical Trial Registration : NCT01994889 (ClinicalTrials.gov) Clinical Trial Registration : NCT02791230 (ClinicalTrials.gov).

Cardiac amyloidosis is a rare disease associated with severe morbidity and mortality. There are three main types of amyloidosis associated with cardiac involvement: light chain (AL), familial or senile (ATTR) and secondary amyloidosis (AA). Cardiac amyloidosis often results in heart failure with preserved left ventricular ejection fraction, may display echocardiographic features of restrictive cardiomyopathy associated with left ventricular hypertrophy or mimic hypertrophic obstructive cardiomyopathy. However, left ventricular systolic dysfunction and normal wall thickness can sometimes be encountered. Imaging studies (echocardiography, bone scintigraphy, cardiac magnetic resonance) and blood and urine analysis are usually the main tools for the diagnosis. Sometimes, a tissue biopsy may be necessary. Treatment, which is constantly improving, will be carried out on two fronts: treatment of the symptoms and complications that the disease already caused and prevention of additional amyloid deposits while managing the concomitant complications. The purpose of this article is to review the management of cardiac amyloidosis.

What Is This Plain Language Summary About?: This plain language summary describes some results of a study called ATTR-ACT. This was the first large study to include people with wild-type and hereditary transthyretin amyloid cardiomyopathy (ATTR-CM for short). ATTR-CM is a type of heart disease that happens when abnormal clumps of protein build up in the heart. This build-up prevents the heart from working properly, causing a condition called heart failure. Wild-type ATTR-CM happens for unknown reasons in some people as they get older. Hereditary ATTR-CM can happen because of changes in people's genes (known as gene variants or mutations)., Important Information About Attr-Act: In this study, 441 people with ATTR-CM took either a medicine called tafamidis or a placebo (a capsule that looked like tafamidis but didn't contain any active medicine) by mouth for 30 months, once a day. The researchers' main aim was to find out how tafamidis treatment affected the risk of people dying or being admitted to the hospital for heart problems. They found that tafamidis lowered these risks by about one-third compared with placebo., What Else Did Researchers Find Out in Attr-Act?: As described in this summary, after ATTR-ACT was completed, researchers looked back at the results from people who took placebo to learn how ATTR-CM progressed without treatment. The researchers found that about 4 in 10 people with wild-type ATTR-CM who took placebo died and 6 in 10 were admitted to the hospital because of heart problems over 30 months. People who took placebo also could not walk as far at the end of the study as they did at the start because their heart function worsened over time., Why Are These Results Important?: By showing how ATTR-CM affects people's health when they do not take treatment, these results highlight the benefits of early diagnosis and treatment of ATTR-CM. ClinicalTrials.gov NCT number: NCT01994889.

This plain language summary describes the results of a study called ATTR-ACT, which was published in the American Journal of Cardiology . In ATTR-ACT, researchers looked at the effects of tafamidis treatment in people with transthyretin amyloid cardiomyopathy (called ATTR-CM for short). Tafamidis is currently available in the USA and other countries as an oral treatment for adults with ATTR-CM. In ATTR-ACT, 441 people with ATTR-CM from 13 different countries took either tafamidis or placebo by mouth for 30 months. First, researchers looked at the effects of tafamidis on the risk of death and hospitalization due to heart problems between the start and the end of the study; they found that these risks were about one-third lower with tafamidis compared with placebo. As described in this summary, researchers also looked at the effects of tafamidis on people's heart failure symptoms, quality of life, and general health over the 30-month study. People who took part in ATTR-ACT rated these effects using questionnaires filled out before, during, and after the study. More people who took tafamidis saw improvement or no change in their heart failure symptoms and quality of life than people who took placebo. In addition, compared with people taking placebo, people taking tafamidis had less worsening of their general health during the study. These results show the benefits of tafamidis in reducing the declines in quality of life and health that often occur with this debilitating disease. Clinical Trial Registration: NCT01994889 (ClinicalTrials.gov).

Transthyretin (TTR) is associated with several human amyloid diseases. Various kinetic stabilizers have been developed to inhibit the dissociation of TTR tetramer and the formation of amyloid fibrils. Most of them are bisaryl derivatives, natural flavonoids, crown ethers and carborans. In this review article, we focus on TTR tetramer stabilizers, genetic therapeutic approaches and fibril remodelers. The binding modes of typical bisaryl derivatives, natural flavonoids, crown ethers and carborans are discussed. Based on knowledge of the binding of thyroxine to TTR tetramer, many stabilizers have been screened to dock into the thyroxine binding sites, leading to TTR tetramer stabilization. Particularly, those stabilizers with unique binding profiles have shown great potential in developing the therapeutic management of TTR amyloidogenesis.

Background: Hereditary transthyretin amyloidosis is caused by pathogenic variants in the TTR gene and typically manifests, alongside cardiac and other organ dysfunctions, with a rapidly progressive sensorimotor and autonomic polyneuropathy (ATTRv-PN) leading to severe disability. While most prospective studies have focussed on endemic ATTRv-PN, real-world data on non-endemic, mostly late-onset ATTRv-PN are limited., Methods: This retrospective study investigated ATTRv-PN patients treated at the Amyloidosis Centre of Heidelberg University Hospital between November 1999 and July 2020. Clinical symptoms, survival, prognostic factors and efficacy of treatment with tafamidis were analysed. Neurologic outcome was assessed using the Coutinho ATTRv-PN stages, and the Peripheral Neuropathy Disability (PND) score., Results: Of 346 subjects with genetic TTR variants, 168 patients had symptomatic ATTRv-PN with 32 different TTR variants identified. Of these, 81.6% had the late-onset type of ATTRv-PN. Within a mean follow-up period of 4.1 ± 2.8 years, 40.5% of patients died. Baseline plasma N-terminal prohormone of brain natriuretic peptide (NT-proBNP) ≥900 ng/l (HR 3.259 [1.421-7.476]; p  = .005) was the main predictor of mortality in multivariable analysis. 64 patients were treated with tafamidis and presented for regular follow-up examinations. The therapeutic benefit of tafamidis was more pronounced when treatment was started early in ATTRv-PN stage 1 (PND scores II vs. I; HR 2.718 [1.258-5.873]; p  = .011)., Conclusions: In non-endemic, mostly late-onset ATTRv-PN, cardiac involvement assessed by NT-proBNP is a strong prognosticator for overall survival. Long-term treatment with tafamidis is safe and efficacious. Neurologic disease severity at the start of treatment is the main predictor for ATTRv-PN progression on tafamidis.

Aim: Examine safety and pharmacodynamics of patisiran alone or with concomitant transthyretin stabilizers from the Phase II open-label extension study and safety and efficacy of patisiran in patients with prior transthyretin stabilizer use from the Phase III APOLLO study. Patients & methods: Post hoc analyses in patients with hereditary transthyretin-mediated amyloidosis with polyneuropathy. Results: Patisiran safety was consistent regardless of concomitant or prior transthyretin stabilizers. In the Phase II open-label extension (n = 27), transthyretin reduction was similar over 24 months, regardless of concomitant transthyretin stabilizers. In APOLLO (n = 225), patisiran-treated groups showed stabilization or improvements in neurological function (modified Neuropathy Impairment Score +7) and quality of life (Norfolk Quality of Life-Diabetic Neuropathy questionnaire) at 18 months, regardless of prior transthyretin stabilizers. Conclusion: Patients benefit from patisiran regardless of transthyretin stabilizer use.

Background: Tafamidis is approved in over 40 countries to delay neurologic progression in patients with transthyretin amyloid polyneuropathy (ATTR-PN). A comprehensive, integrated analysis of safety data from interventional, observational and surveillance studies of tafamidis in ATTR-PN patients was conducted. Methods: Safety data from all sponsored, completed, or ongoing, Phase 2/3 studies of tafamidis in ATTR-PN patients as of 3 January 2017 were pooled. Also assessed were safety data from the ongoing Transthyretin Amyloidosis Outcomes Survey (THAOS) as of 3 January 2017 and post-marketing surveillance reports as of 31 March 2017. Results: There were 137 patients in Phase 2/3 studies (mean duration of tafamidis exposure, 44.2 months), with 134 (97.8%) experiencing ≥1 treatment-emergent adverse event (TEAE) and 46 (33.6%) ≥1 treatment-emergent serious adverse event (TESAE). The most common TEAEs were diarrhoea (26.3%), urinary tract infection (UTI; 25.5%) and influenza (21.2%). In THAOS, 661 subjects had tafamidis exposure (mean duration, 27.6 months), with 250 (37.8%) experiencing ≥1 TEAE and 96 (14.5%) ≥1 TESAE. The most common TEAE was UTI (6.1%). Post-marketing surveillance reports generally reflected the known safety profile of tafamidis. Conclusions: This analysis did not reveal any significant new safety findings; tafamidis was generally safe and well tolerated in ATTR-PN patients. ClinicalTrials.gov: NCT00409175, NCT00791492, NCT00630864, NCT01435655, NCT00925002, and NCT00628745.

There have now been randomized controlled trials of four different therapeutics for hereditary amyloid polyneuropathy related to transthyretin (TTR) deposition and one for amyloidotic cardiomyopathy of both genetic and sporadic origin. It is likely that in the next few months those not already approved by either the US Food and Drug Administration (FDA) and/or the European Medicines Authority (EMA) will receive similar approvals for treatment for all or particular groups of patients. This is a far cry from circumstances less than 10 years ago when the only available therapy was gene replacement by liver transplant. The randomized controlled trials have shown that all the treatments (tafamidis, diflunisal, patisiran, and inotersen) are effective in the context of a clinical trial. However, we have very little idea of whether individual patients will respond in an equally positive way to all the drugs or whether there will be some who respond better to one or another or not respond at all, nor do we know whether combinations will be additive or synergistic. We lack validated markers of clinical response. While the small molecule TTR stabilizers increase serum TTR levels, the RNA-based drugs lower serum TTR. In the latter case, it is not clear that the reduction in serum TTR is related to the clinical response in a 1:1 fashion. Pharmaceutical companies have made substantial investments in the development of these agents and will clearly attempt to recoup those investments quickly. It is incumbent upon those of us who care for these patients to develop ways to assess the effects of therapy in the shortest possible time at the lowest possible cost. The better we are able to accomplish this the more likely it is that we will be able to treat the most patients in the most clinically efficient fashion regardless of their economic status. We now have the drugs we just have to figure out who should get them and when.

Transthyretin (TTR) related cardiomyopathy is an underdiagnosed cause of heart failure but is increasingly recognized in various settings - from patients admitted with heart failure to symptomatic aortic stenosis - and is rapidly becoming the most frequent form of systemic amyloidosis. Following the recent publication of the landmark ATTR-ACT trial that showed tafamidis to be the first treatment to improve survival in patients with TTR-related cardiac amyloidosis and heart failure, we reviewed the drug's rationale, characteristics and evidence supporting its use in TTR amyloidosis.

Background: Ocular abnormalities have been known to occur in hereditary amyloidotic polyneuropathy since the 1950s. While vitreous opacities and scalloped pupils were described early it has become evident that every component of the eye from the conjunctiva to the retinal vasculature can be involved. Reports from the major centres in Japan, Portugal and Sweden, which primarily treat patients with ATTRV30M, have indicated that with the increased longevity seen in patients treated with liver transplantation the frequency of the more severe eye findings, notably vitreous opacities and subsequent glaucoma, are being detected more frequently., Methods: In an attempt to confirm that the experience was similar in a broader range of locales we performed a survey of ten treatment centres in eight countries to determine the frequency of severe ocular abnormalities (vitreous opacities and glaucoma) in 804 patients with V30M disease and whether there was any relationship to treatment with liver transplantation or the transthyretin stabilizer tafamidis., Results: The data indicate that the frequency of these abnormalities increases with increasing duration of disease. In patients broadly matched for duration of disease the frequency was higher in subjects who had undergone liver transplantation than in those who were untreated., Conclusions: Retrospective surveys are subject to a number of potential biases. In this case, the major potential confounders were defining the time of disease onset and physician bias in choice of therapy, particularly regarding the choice of patients and the time in their course when they should undergo liver transplantation, and when and whether they should receive tafamidis. Nonetheless it appears that the incidence of severe ocular abnormalities in V30M subjects from centres around the world is similar to those found in centres in the areas endemic for this variant protein. The incidence increased with duration of disease regardless of therapy with the highest frequencies seen in patients more than ten years after diagnosis who had undergone liver transplantation.

Background: Tafamidis, a non-NSAID highly specific transthyretin stabilizer, delayed neurologic disease progression as measured by Neuropathy Impairment Score-Lower Limbs (NIS-LL) in an 18-month, double-blind, placebo-controlled randomized trial in 128 patients with early-stage transthyretin V30M familial amyloid polyneuropathy (ATTRV30M-FAP). The current post hoc analyses aimed to further evaluate the effects of tafamidis in delaying ATTRV30M-FAP progression in this trial., Methods: Pre-specified, repeated-measures analysis of change from baseline in NIS-LL in this trial (ClinicalTrials.gov NCT00409175) was repeated with addition of baseline as covariate and multiple imputation analysis for missing data by treatment group. Change in NIS-LL plus three small-fiber nerve tests (NIS-LL + Σ3) and NIS-LL plus seven nerve tests (NIS-LL + Σ7) were assessed without baseline as covariate. Treatment outcomes over the NIS-LL, Σ3, Σ7, modified body mass index and Norfolk Quality of Life-Diabetic Neuropathy Total Quality of Life Score were also examined using multivariate analysis techniques., Results: Neuropathy progression based on NIS-LL change from baseline to Month 18 remained significantly reduced for tafamidis versus placebo in the baseline-adjusted and multiple imputation analyses. NIS-LL + Σ3 and NIS-LL + Σ7 captured significant treatment group differences. Multivariate analyses provided strong statistical evidence for a superior tafamidis treatment effect., Conclusions: These supportive analyses confirm that tafamidis delays neurologic progression in early-stage ATTRV30M-FAP., Trial Registration Number: NCT00409175.

Amyloid neuropathies of acquired or genetic origin are disabling and life-threatening, until recently there were few treatment options available. Poor prognosis is related to progressive neuropathy and associated, although often underdiagnosed, cardiac involvement in specific transthyretin (TTR) gene mutations. Recent progress has modified prognosis and management of amyloid neuropathies. In TTR-familial amyloidosis with polyneuropathy, major changes have occurred over the last 30 years: better knowledge concerning genetics, phenotypes and epidemiology, and the advent of possible treatments. Liver transplantation, first performed in 1990, stopped disease progression, thus doubling survival in early onset V30M patients. More recently tetramer stabilizers (Tafamidis and Diflunisal) showed a significant reduction of progression of neuropathic scores; Tafamidis is now recommended in Stage I patients. Two multicentric clinical trials are now ongoing to evaluate TTR gene silencing by antisense Oligonucleotides (ASO) or siRNA. In the near future we should have new therapeutical options for patients with amyloid neuropathy.

Introduction: Transthyretin (TTR)-related hereditary amyloidosis is an adult-onset, dominantly inherited, systemic neurodegenerative disease endemic in some populations. Stabilization of the native structure of TTR by small-molecule ligands has recently proved effective in slowing neurological progression. Two drugs, tafamidis and diflunisal, are now available for most patients, particularly in the early stage of the disease. However, this disorder remains life threatening with several unmet needs. There are great expectations for a number of novel agents undergoing investigation., Areas Covered: The authors review the current investigational drugs for the treatment of TTR amyloidosis according to the different steps of the fibrillogenesis process they target. Innovative approaches include suppression of TTR secretion, prevention of TTR misfolding by stronger stabilizers identified through structure-based design and high-throughput screening methodologies as well as the redirection of pathogenic aggregates toward nontoxic species and reabsorption of deposits through amyloid disrupters and immunotherapy., Expert Opinion: Suppression of TTR synthesis by antisense oligonucleotides and small-interfering RNA is presently one of the most promising therapeutic approaches. However, well-designed clinical trials are required to establish their safety and efficacy compared with liver transplantation, tafamidis and diflunisal. With a longer time frame, it may be possible to develop combination therapies that target multiple steps of the aggregation process that could provide the best long-life effective treatments for this devastating disease.