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This Study Will Examine the Clinical Effectiveness of Tafamidis in Patients With Mixed Phenotype Hereditary Transthyretin Amyloidosis

Completed
Conditions
Hereditary Transthyretin Amyloidosis (ATTRv) Cardiomyopathy (CM), Mixed Phenotype
Interventions
Registration Number
NCT05139680
Lead Sponsor
Pfizer
Brief Summary

This study will examine the clinical effectiveness of Tafamidis in patients with Mixed Phenotype Hereditary Transthyretin Amyloidosis using data that already exist in patients' medical records.

Detailed Description

Not available

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
10
Inclusion Criteria
  • Age ≥18 years at diagnosis
  • Diagnosed with ATTRv-CM, mixed phenotype
  • Treated with tafamidis (VYNDAQEL 80 mg [four 20-mg tafamidis meglumine capsules] orally once daily or VYNDAMAX 61 mg [one 61-mg tafamidis capsule] orally once daily) for ≥6 months
  • Have had ≥1 pre- and ≥2 post-treatment neurologic assessments
Exclusion Criteria
  • History of organ transplant
  • Wild-type TTR genotype
  • Individuals who are non-ambulatory
  • Prior treatment with any disease-modifying therapy (investigational or approved) alone or in combination, except tafamidis, as either VYNDAQEL 80 mg (four 20-mg tafamidis meglumine capsules) orally once daily or VYNDAMAX 61 mg (one 61-mg tafamidis capsule) orally once daily
  • Peripheral neuropathy attributed to causes other than ATTR amyloidosis (e.g., diabetes mellitus, B12 deficiency, HIV infection)

Study & Design

Study Type
OBSERVATIONAL
Study Design
Not specified
Arm && Interventions
GroupInterventionDescription
Patients with mixed phenotype ATTRv-CMtafamidisHereditary ATTR-CM patients presenting with mixed phenotype
Primary Outcome Measures
NameTimeMethod
Neurologic Disease Progression: Number of Participants According to Muscle Weakness Assessment by Neuropathy Impairment Score (NIS) Subscale ScorePre-treatment baseline period to post-treatment period (data for specified duration was extracted from medical records and observed retrospectively in this study from 08-Mar-2023 to 19-May-2023)

Neurologic disease progression meant worsening of neurologic function over the time, is assessed by NIS subscale score in this outcome measure. NIS is a composite neurologic impairment score that assesses muscle weakness, sensation, and reflexes by physical exam. NIS subscale for muscle weakness assessment has a score range from 0 (minimum value) to 192 (maximum value). Lower scores indicates normal to mild impairment. Participants were classified as: no change, increase or decrease in NIS subscale scores from pre-treatment baseline period to post-treatment period. Pre-treatment baseline period: at least 6 months and up to 12 months before treatment initiation. Post-treatment period: at least 6 months after treatment initiation with a +/- 3 months window.

Neurologic Disease Progression: Number of Participants According to Walking Capacity Assessment by Polyneuropathy Disability (PND) ScorePre-treatment baseline period to post-treatment period (data for specified duration was extracted from medical records and observed retrospectively in this study from 08-Mar-2023 to 19-May-2023)

Neurologic disease progression meant worsening of neurologic function over the time, is assessed by PND score in this outcome measure. PND is a scoring system to assess participants' walking capacity. It consists of four stages from stage 0 (no impairment) to stage IV (confined to a wheelchair or bedridden). Lower scores indicates normal to mild impairment. Participants were classified as: no change, increase or decrease in PND scores from pre-treatment to post -treatment period. Pre-treatment baseline period: at least 6 months and up to 12 months before treatment initiation. Post-treatment period: at least 6 months after treatment initiation with a +/- 3 months window.

Neurologic Disease Progression: Number of Participants According to Muscle Strength Assessment by Medical Research Council (MRC) ScalePre-treatment baseline period to post-treatment period (data for specified duration was extracted from medical records and observed retrospectively in this study from 08-Mar-2023 to 19-May-2023)

Neurologic disease progression meant worsening of neurologic function over the time, is assessed by MRC scale in this outcome measure. MRC assessed muscle strength using a score of 0 (no contraction) to 5 (normal power), to grade the power of a particular muscle group in relation to the movement of a single joint. The higher scores mean a better outcome. Participants were classified as: no change, increase or decrease in MRC scale score from pre-treatment to post-treatment period. Pre-treatment baseline period: at least 6 months and up to 12 months before treatment initiation. Post-treatment period: at least 6 months after treatment initiation with a +/- 3 months window.

Secondary Outcome Measures
NameTimeMethod
Modified Body Mass Index (mBMI)Pre-treatment baseline period, post-treatment period (data for specified duration was extracted from medical records and observed retrospectively in this study from 08-Mar-2023 to 19-May-2023)

mBMI was calculated as the product of BMI in kilogram per meter square (kg/m\^2) and serum albumin in gram per litre (g/L) to compensate for peripheral edema. Pre-treatment baseline period: at least 6 months and up to 12 months before treatment initiation. Post-treatment period: at least 6 months after treatment initiation with a +/- 3 months window.

Trial Locations

Locations (1)

Pfizer

🇺🇸

New York, New York, United States

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