Hereditary ATTR (hattr) Amyloidosis: Polyneuropathy An Overview. Identifying the link can lead to a crucial diagnosis

Hereditary ATTR (hattr) Amyloidosis: Polyneuropathy An Overview Identifying the link can lead to a crucial diagnosis

Hereditary ATTR (hattr) Amyloidosis: Polyneuropathy Information about mechanism of disease, signs and symptoms, diagnosis, and treatment

What is amyloidosis? The amyloidoses are a heterogeneous group of disorders characterized by deposition of insoluble misfolded protein aggregates, known as amyloid fibrils, in tissues 1,2 36 unique amyloid fibril proteins have been identified in humans 2 Amyloidosis can be acquired or hereditary, and systemic or localized 3 1. Shin S, et al. Mt Sinai J Med. 2012:79(6):733-748. 2. Sipe JD, et al. J Protein Fold Disord. 2016:23(4):209-213. 3. Rowczenio OM, et al. Human Mutat. 2014;35(9): E2403-E2412.

The most common types of systemic amyloidosis 1 Four types are seen most frequently 1,2 : Type Precursor Protein Organs/Systems Targeted AL lmmunoglobulin light chain All organs except central nervous system AA (Apo) serum amyloid A All organs except central nervous system Aβ 2 M ATTR β2-microglobulin, wild type β2-microglobulin, variant Transthyretin, wild type Transthyretin, variants Musculoskeletal system Autonomic nervous system Heart mainly in men, tenosynovium Nerves, heart, and GI tract Nomenclature: The amyloidoses are named based on the disease-causing protein, with an A designating amyloid fibril. For example, when the type is ATTR the A designates amyloid fibril, and the TTR designates the transthyretin protein. 3 1. Hazenberg BPC. Rheum Dis Clin N Am. 2013;39:323-345. 2. Damy T, et al. J Cardiovasc Transl Res. 2015;8(2):117-127. 3. Sipe JD, et al. J Protein Fold Disord. 2016:23(4):209-213.

Types of ATTR amyloidosis wtattr hattr Description Etiology Symptoms Time to Mortality Wild-type ATTR (wtattr) amyloidosis, formerly known as senile systemic amyloidosis (SSA), is a nonhereditary, progressive disease of undefined etiology. 1-3 Misfolded transthyretin (TTR) proteins accumulate as amyloid fibrils in multiple organs, including the heart. 4,5 Can cause cardiomyopathy and neuropathy, resulting in heart failure and mortality. 4,6,7 Hereditary ATTR (hattr) amyloidosis is an inherited, rapidly progressive, life-threatening disease. 8-10 Caused by a mutation in the TTR gene that results in misfolded TTR proteins accumulating as amyloid fibrils in multiple tissues including the nerves, heart, and gastrointestinal tract. 1,8,11 A multisystemic disease with a heterogeneous clinical presentation that includes sensory and motor, autonomic (e.g., diarrhea, erectile dysfunction, hypotension), and cardiac symptoms. 8,12,13 Can lead to significant morbidity, disability, and mortality. 4,8-10 Within 2 to 6 years (median overall survival of 3.6 years). 4,6 Within 2 to 15 years. 4,8 1. Hawkins PN, et al. Ann Med. 2015;47(8):625-638. 2. Dubrey S, et al. Postgrad Med J. 2015;91(1078):439-448. 3. Kourelis TV, et al. Expert Rev Cardiovasc Ther. 2015;13(8):945-961. 4. Castaño A, et al. Heart Fail Rev. 2015;20(2):163-178. 5. Westermark P, et al. Amyloid. 2003;10(suppl 1):48-54. 6. Pinney JH, et al. J Am Heart Assoc. 2013;2:e000098 doi:10.1161/jaha.113.000098. 7. Coelho T, et al. Curr Med Res Opin. 2013;29(1):63-76. 8. Hanna M. Curr Heart Fail Rep. 2014;11(1):50-57. 9. Mohty D, et al. Arch Cardiovasc Dis. 2013;106(10):528-540. 10. Adams D, et al. Neurology. 2015:85(8):675-682. 11. Damy T, et al. J Cardiovasc Transl Res. 2015;8(2):117-127. 12. Conceição I, et al. J Peripher Nerv Syst. 2016;21(1):5-9. 13. Shin SC, et al. Mt Sinai J Med. 2012;79(6):733-748.

Formation of amyloid fibrils in hattr amyloidosis 1,2 Liver TTR TTR Misfolded Amyloid Fibrils Amyloid Deposits TTR is primarily synthesized in the liver Normally, TTR is a tetramer composed of four identical monomers In hattr amyloidosis, the tetramer becomes destabilized, resulting in protein misfolding and aggregation into amyloid fibrils Amyloid fibrils are deposited at multiple sites in the body, including the nerves, heart, and the GI tract, causing damage that leads to clinical symptoms 1. Sekijima Y. J Neurol Neurosurg Psychiatry. 2015;86(9):1036-1043. 2. Hawkins PN, et al. Ann Med. 2015;47(8):625-638.

hattr amyloidosis a hereditary condition hattr amyloidosis is an autosomal dominant disease; thus, a person only needs to inherit one copy of the mutated TTR gene from one parent to develop the condition 1,2 Penetrance is variable, and some individuals may remain asymptomatic despite having a TTR mutation 1-3 1. Hanna M. Curr Heart Fail Rep. 2014;11(1):50-57. 2. Ando Y, et al. Orphanet J Rare Dis. 2013;8:31. 3. Hawkins PN, et al. Ann Med. 2015;47(8):625-638.

TTR gene mutations More than 120 different TTR gene mutations have been discovered 1-3 The most common mutation is Val30Met. Individuals with this mutation often initially present with polyneuropathy Prevalence is higher in Portugal, Sweden, Japan, Brazil, and Spain The Val122Ile mutation is common in individuals who initially present with cardiomyopathy; found in 3 to 4% of the African American populations Symptoms can present differently, even among people in the same family and in the same mutation 3 1. Sekijima Y. J Neurol Neurosurg Psychiatry. 2015;86(9):1036-1043. 2. Rowczenio DM, et al. Hum Mutat. 2014;35(9):E2403-E2412. 3. Ando Y, et al. Orphanet J Rare Dis. 2013;8:31.

hattr amyloidosis affects an estimated 50,000 patients worldwide 1 Polyneuropathy Cardiomyopathy Disease symptoms fall along a spectrum In the disease continuum of hattr amyloidosis: Some patients present primarily with polyneuropathy symptoms, historically known as familial amyloidotic polyneuropathy (FAP) 1,2 Other patients present primarily with cardiomyopathy symptoms, historically known as familial amyloidotic cardiomyopathy (FAC) 1,2 A substantial proportion of patients with hattr amyloidosis presents with a mixed phenotype 3,4 1. Hawkins PN, et al. Ann Med. 2015;47(8):625-638. 2. Ando Y, et al. Orphanet J Rare Dis. 2013;8:31. 3. Rapezzi C, et al. Eur Heart J. 2013;34(7):520-528. 4. Adams D, et al. In: The XVth International Symposium on Amyloidosis. Uppsala, Sweden: ISA International Society of Amyloidosis; July 3-7, 2016. PA 82.

hattr amyloidosis: a life-threatening, multisystem disease 1-4 Because amyloid fibrils are deposited in tissues throughout the body, including the nerves, heart, and GI tract, patients with hattr amyloidosis can present across a spectrum that includes sensory and motor, autonomic, and cardiac symptoms 1-6 In addition to the varied symptom presentation, age of onset varies among patients with a median age of 39 years, with some presenting as early as their 20s 7,8 1. Conceição I, et al. J Peripher Nerv Syst. 2016;21(1):5-9. 2. Mohty D, et al. Arch Cardiovasc Dis. 2013;106(10):528-540. 3. Shin SC, et al. Mt Sinai J Med. 2012;79(6):733-748. 4. Hanna M. Curr Heart Fail Rep. 2014;11(1):50-57. 5. Damy T, et al. J Cardiovasc Transl Res. 2015;8(2):117-127. 6. Hawkins PN, et al. Ann Med. 2015;47(8):625-638. 7. Ando Y, et al. Orphanet J Rare Dis. 2013;8:31. 8. Coelho T, et al. Curr Med Res Opin. 2013;29(1):63-76.

Constellation of possible signs and symptoms of hattr amyloidosis 1 Progressive dementia Headache Ataxia Seizures Spastic paresis Stroke-like episodes Vitreous opacification Glaucoma Abnormal conjunctival vessels Papillary abnormalities Proteinuria Renal failure Orthostatic hypotension Recurrent urinary tract infections (due to urinary retention) Sexual dysfunction Sweating abnormalities Conduction block Cardiomyopathy Arrhythmia Nausea & vomiting Early satiety Diarrhea Severe constipation Alternating episodes of diarrhea & constipation Unintentional weight loss Neuropathic pain Altered sensation (i.e., change in sensitivity to pain and temperature) Numbness and tingling Muscle weakness Impaired balance Difficulty walking Reference: 1. Conceição I, et al. J Peripher Nerv Syst. 2016;21(1):5-9.

Symptom presentation can vary among patients 1 In a multicenter study that included 186 individuals with hattr amyloidosis, 58% (109/186) of hattr amyloidosis patients presented with a mixed phenotype characterized by cardiac and neurologic involvement 2 Percentage of patients 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Sensory and motor Autonomic Cardiac Baseline clinical characteristics of 186 individuals with hereditary ATTR amyloidosis in a multicenter study 2 Echocardiographic abnormalities included increased LV wall thickness, granular sparkling of ventricular myocardium, increased thickness of atrioventricular valves or interatrial septum, or pericardial effusion 2 Electrocardiographic abnormalities included advanced A-V block or intraventricular conduction disturbances 2 1. Ando Y, et al. Orphanet J Rare Dis. 2013;8:31. 2. Rapezzi C, et al. Eur Heart J. 2013;34(7):520-528. https://doi.org/10.1093/eurheartj/ehs123.

Symptoms of hattr amyloidosis can progress quickly, leading to life-threatening dysfunction 1-3 As the disease progresses, symptoms increase in severity, leading to significant disability, decreased quality of life, and untimely death 3,4 hattr amyloidosis can lead to mortality within 2 to 15 years 1,5 Due to the variability of the disease, progression of symptoms can also be considerably different from patient to patient 6 Due to the rapid natural progression of the disease, patients with hattr amyloidosis require an early and accurate diagnosis. 4,7,8 1. Hanna M. Curr Heart Fail Rep. 2014;11(1):50-57. 2. Mohty D, et al. Arch Cardiovasc Dis. 2013;106(10):528-540. 3. Adams D, et al. Neurology. 2015:85(8):675-682. 4. Adams D, et al. Curr Opin Neurol. 2016;29(suppl 1):S14-S26. 5. Castaño A, et al. Heart Fail Rev. 2015;20(2):163-178. 6. Ando Y, et al. Orphanet J Rare Dis. 2013;8:31. 7. Conceição I, et al. J Peripher Nerv Syst. 2016;21(1):5-9. 8. Obici L, et al. Curr Opin Neurol. 2016;29(suppl 1):S27-S35.

Consider hattr amyloidosis in your differential diagnosis Because the symptoms of hattr amyloidosis may overlap with those of other diseases, detailed diagnostic history may help to identify patients with hattr amyloidosis. 1-4 Diseases with symptoms that overlap with those of hattr amyloidosis 1-4 Diagnostic assessment 5-9 Potential diagnoses 5-9 Ataxia and foot numbness Motor involvement Upper limb neuropathy Weakness in feet, ankles, legs Pain and tingling with alcohol abuse Polyneuropathy with diabetes Polyneuropathy with evidence of amyloid deposition CIDP ALS Motor polyradiculoneuropathy Carpal tunnel syndrome Idiopathic polyneuropathy Paraneoplastic neuropathy CIDP Motor neuron diseases Charcot-Marie-Tooth disease Alcoholic neuropathy Diabetic neuropathy AL amyloidosis AA amyloidosis For patients with neuropathic symptoms, the most common misdiagnosis previously received is CIDP 10 AA=amyloid A; AL=amyloid light chain; ALS=amyotrophic lateral sclerosis; CIPD=chronic inflammatory demyelinating polyneuropathy. 1. Adams D, et al. Curr Opin Neurol. 2016;29(suppl 1):S14-S26. 2. Conceição I, et al. J Peripher Nerv Syst. 2016;21(1):5-9. 3. Ando Y, et al. Orphanet J Rare Dis. 2013;8:31. 4. Ruberg FL, et al. Circulation. 2012;126(10):1286-1300. 5. Adams D, et al. Curr Neurol Neurosci Rep. 2014;14(3):435. 6. Adams D, et al. Curr Opin Neurol. 2012;25(5):564-572. 7. Szigeti K, et al. Eur J Hum Genet. 2009;17(6):703-710. 8. Zeng L, et al. J Pain Res. 2017;10:219-228. 9. Shin SC, et al. Mt Sinai J Med. 2012;79(6):733-748. 10. Cortese A, et al. J Neurol Neurosurg Psychiatry. 2017;0(0). doi:10.1136/jnnp-2016-315262.

Recognize the red-flag symptoms. Suspect hattr amyloidosis. Red-flag symptom clusters associated with hattr amyloidosis Progressive symmetric sensory-motor neuropathy and 1 of the following 1 : Bilateral carpal tunnel syndrome Nephropathy (e.g., proteinuria or renal failure) Early autonomic dysfunction (e.g., erectile dysfunction or postural hypotension) Gastrointestinal complaints (e.g., chronic diarrhea, constipation, or diarrhea/constipation) Unexplained weight loss Cardiovascular manifestations (e.g., conduction block, cardiomyopathy, or arrhythmia) Vitreous opacities Positive family history Additional signs: Rapid disease progression and failure to respond to immunomodulatory treatment Obtaining a family history is an important step in the diagnostic process 1-3 1. Conceição I, et al. J Peripher Nerv Syst. 2016;21(1):5-9. 2. Adams D, et al. Curr Opin Neurol. 2016;29(suppl 1):S14-S26. 3. Tan BY, et al. Circ Cardiovasc Genet. 2012;5(6):697-705.

Confirming an hattr amyloidosis diagnosis Diagnostic tools for patients presenting with polyneuropathy 1-3 Complete neurologic examination Electromyography Sympathetic skin response (SSR) Heart rate deep breathing Sudoscan assessment of electrochemical skin conductance Medical history Laboratory tests to exclude mimicking polyneuropathies Genetic analysis to determine pathologic mutation Tissue biopsy + Congo red staining Salivary gland Abdominal subcutaneous adipose tissue Rectal mucosa Sural nerve Skin Gastric Identification of amyloid protein Immunohistochemistry Mass spectrometry 1. Adams D, et al. Curr Opin Neurol. 2016;29(suppl 1):S14-S26. 2. Ando Y, et al. Orphanet J Rare Dis. 2013;8:31. 3. Castro J, et al. Clin Neurophysiol. 2016;127(5):2222-2227.

Genetic screening If patient symptoms and a family history lead to a suspicion of hattr amyloidosis, genetic counseling can help patients understand the potential diagnosis, the genetic screening process, and the implications of the disease.

hattr amyloidosis: linking pathophysiology to potential therapeutic approaches 1,2 Pathophysiology Liver TTR TTR Misfolded TTR Amyloid Fibrils Suppression of amyloidogenic TTR Liver transplantation Antisense oligonucleotides (ASO) RNAi therapeutics Tetramer Stabilizers Inhibition of amyloid deposits Monoclonal antibody Fibril disruptors THERAPEUTIC APPROACHES* *This visual represents approved and investigational approaches. Current investigational approaches: TTR tetramer stabilizers, RNAi therapeutics, ASOs, monoclonal antibodies, and fibril disruptors 1-3 1. Ueda M, et al. Transl Neurodegener. 2014;doi:10.1186/2047-9158-3-19. 2. Sekijima Y. J Neurol Neurosurg Psychiatry. 2015;86(9):1036-1043. 3. Richards DB, et al. N Engl J Med. 2015;373(12):1106-1114.

Current treatment options: liver transplant Orthotopic liver transplant removes approximately 95% of the production of TTR. It has improved survival rates but does not permanently halt disease progression and requires lifelong use of immunosuppressants 1,2 Transplant may be less effective for patients who present primarily with cardiomyopathy The limited availability of organs, as well as the exclusion of older patients and patients with advanced disease or with comorbidities, warrants the development of other treatment options 1. Sekijima Y. J Neurol Neurosurg Psychiatry. 2015;86(9):1036-1043. 2. Ando Y, et al. Orphanet J Rare Dis. 2013;8:31.

Investigational therapies in development There are multiple investigational therapies in development that target different points in the disease pathway 1-4 Therapies that may help to reduce fibril accumulation: Monoclonal antibodies may suppress ATTR amyloid deposition by binding to amyloid fibrils and targeting them for immune system destruction 1,2,4 Fibril disrupters bind to amyloid fibrils and disrupt their association 1,2 Therapies that may address the underlying cause of amyloidosis: Antisense oligonucleotides (ASOs) are short chemically modified oligonucleotides that bind to TTR mrna and prevent production of TTR protein via ASO-RNAse H mediated cleavage 1-3 RNAi therapeutics are double stranded small interfering RNAs that bind to transthyretin (TTR) messenger RNA (mrna) and prevent production of TTR protein via the RNA interference (RNAi) pathway 1-3 1. Ueda M, et al. Transl Neurodegener. 2014;doi:10.1186/2047-9158-3-19. 2. Sekijima Y. J Neurol Neurosurg Psychiatry. 2015;86(9):1036-1043. 3. Ando Y, et al. Orphanet J Rare Dis. 2013;8:31. 4. Richards DB, et al. N Engl J Med. 2015;373(12):1106-1114.

Treatments that stabilize TTR protein TTR tetramer stabilizers bind to the thyroxine binding site on the TTR protein, stabilizing circulating TTR tetramers and preventing the dissociation into monomers, but do not inhibit the synthesis of disease-causing protein 1,2 1. Sekijima Y. J Neurol Neurosurg Psychiatry. 2015;86(9):1036-1043. 2. Ando Y, et al. Orphanet J Rare Dis. 2013;8:31.

Recognize the signs. Suspect hattr amyloidosis. Hereditary ATTR (hattr) amyloidosis is an autosomal dominant disease 1-3 hattr amyloidosis is caused by a mutation in the transthyretin (TTR) gene that results in misfolded TTR proteins accumulating as amyloid fibrils in multiple sites including the nerves, heart, and GI tract 1,2,4 Affects multiple organs, resulting in varying symptoms 5-7 hattr amyloidosis can lead to mortality within 2 to 15 years 1,8 Obtaining a family history is an important step in the diagnostic process 5,9,10 There are multiple investigational therapies in development that target different points in the disease pathway 3,11-13 Access this information and these updates, and learn about genetic screening made available at no charge in the US, by visiting: https://hattramyloidosis.com 1. Hanna M. Curr Heart Fail Rep. 2014;11(1):50-57. 2. Hawkins PN, et al. Ann Med. 2015;47(8):625-638. 3. Ando Y, et al. Orphanet J Rare Dis. 2013;8:31. 4. Damy T, et al. J Cardiovasc Transl Res. 2015;8(2):117-127. 5. Conceição I, et al. J Peripher Nerv Syst. 2016;21(1):5-9. 6. Mohty D, et al. Arch Cardiovasc Dis. 2013;106(10):528-540. 7. Shin SC, et al. Mt Sinai J Med. 2012;79(6):733-748. 8. Castaño A, et al. Heart Fail Rev. 2015;20(2):163-178. 9. Adams D, et al. Curr Opin Neurol. 2016;29(suppl 1):S14- S26. 10. Tan BY, et al. Circ Cardiovasc Genet. 2012;5(6):697-705. 11. Ueda M, et al. Transl Neurodegener. 2014; doi:10.1186/2047-9158-3-19. 12. Sekijima Y. J Neurol Neurosurg Psychiatry. 2015;86(9):1036-1043. 13. Richards DB, et al. N Engl J Med. 2015;373(12):1106-1114.