Clinical Trial: The Effect Of Tafamidis For The Transthyretin Amyloid Polyneuropathy Patients With V30M Or Non-V30M Transthyretin

Study Status: Completed
Recruit Status: Completed
Study Type: Interventional

Official Title: The Effect On Transthyretin Stabilization, Safety, Tolerablity, Efficacy And Pharmacokinetics Of Orally Administered Tafamidis In Transthyretin Amyloid Polyneuropathy Pati

Brief Summary: Tafamidis has been developed as an oral specific stabilizer of transthyretin tetramer.

Detailed Summary:
Sponsor: Pfizer

Current Primary Outcome: Number of Participants With Transthyretin (TTR) Stabilization at Week 8 Compared With Baseline as Measured by a Validated Immunoturbidimetric Assay [ Time Frame: 8 weeks ]

Original Primary Outcome: TTR stabilization at Week 8 compared with Baseline, as measured by a validated immunoturbidimetric assay. [ Time Frame: 8 weeks ]

Current Secondary Outcome:

• Change From Baseline in Neuropathy Impairment Score (NIS); NIS (Total), NIS-LL (Lower Limb) and NIS-UL (Upper Limb) at Week 26, Week 52 and Week 78 [ Time Frame: Baseline, Week 26, Week 52, Week 78 ]
  The NIS provides a total body single score of neuropathic deficits (score range: 0-122, higher score = more deficit), comprising subset scores for cranial nerves, muscle weakness, reflexes, and sensation (based on mean of 2 scores in 1 week period; each item scored separately for left and right). The NIS-LL is a subscale that provides a score for the lower limbs functions (muscle weakness, reflexes and sensation in great toe) and has a score range of 0-44 (higher score = more deficit). The NIS-UL is a subscale that provides a score for the upper body functions (muscle weakness [including cranial nerves], reflexes and sensation in finger) and has a score range of 0-78 (higher score = more deficit). The components for cranial nerves and muscle weakness are scored from 0 (Normal) to 4 (Paralysis), and those for reflexes and sensation from 0 (Normal) to 2 (Absent). For all items, higher scores indicate greater impairment.
• Change From Baseline in Scores of the Total Quality of Life (TQOL) and 5 Domains as Measured by the Norfolk QOL - Diabetic Neuropathy (Norfolk QOL-DN) at Week 26, Week 52 and Week 78. [ Time Frame: Baseline, Week 26, Week 52, Week 78 ]
  Norfolk QOL-DN is a 35-item participant-rated questionnaire. It consists of 5 domains: Physical Functioning/Large Fiber [score range: -4 - 56] , Activities of Daily Living (ADL) [0 - 20], Symptoms [0 - 32], Small Fiber [0 - 16] and Autonomic [0 - 12]. Total of quality of life (TQOL) score is the sum of all five domains with a range of -4 to 136 (Pfizer Data Standards). Higher scores on each item of the Norfolk QOL-DN TQOL indicate worse quality of life.
• Change From Baseline in Summated 7 Nerve Tests Normal Deviate Score (∑ 7 NTs Nds) as Measured by Nerve Conduction Studies (NCS), Vibration Detection Threshold (VDT) and Heart Rate Response to Deep Breathing (HRDB) at Week 26, Week 52, and Week 78 [ Time Frame: Baseline, Week 26, Week 52, Week 78 ]
  The Σ7 NTs nds measures primarily large-fiber function. It is a composite score derived from five NCS attributes (peroneal nerve distal motor latency, peroneal nerve compound muscle action potential, peroneal nerve motor conduction velocity, tibial nerve distal motor latency, and sural nerve sensory nerve action potential amplitude) along with VDT obtained in great toes by Quantitative Sensory Testing (QST), and HRDB value. It is defined as 7 times the mean of non-missing values of, the five normal deviates of NCS, HRDB, and average normal deviate for VDT of toes. Score was determined through reference to normal values for age, sex, height and abnormalities scored. Total score range is approximately -26 to 26, where higher score=worse nerve function.
• Change From Baseline in Summated 3 Nerve Tests Small Fiber Normal Deviate Score (∑ 3 NTSF Nds) as Measured by Cooling and Heat Pain Thresholds by QST and HRDB at Week 26, Week 52 and Week 78 [ Time Frame: Baseline, Week 26, Week 52, Week 78 ]
  The Σ3 NTSF nds measures small-fiber function. It is a composite score defined as 3 times the mean of non-missing values of normal deviates of cooling threshold for lower limbs, heat pain intermediate response for lower limbs, and HRDB. The total score range is approximately -11.2 to 11.2, with a higher score demonstrating worse nerve function.
• Change From Baseline in Modified Body Mass Index (mBMI) at Week 8, Week 26, Week 52 and End of Study [ Time Frame: Baseline, Week 8, Week 26, Week 52, End of Study ]
  The mBMI was calculated by multiplying the BMI (the weight in kilograms divided by the square of the height in meters) by serum albumin level (gram/liter). Change in mBMI was calculated as the mBMI at the given week minus the Baseline mBMI.
• Change From Baseline in Ambulatory Status at Week 26, Week 52 and Week 78 [ Time Frame: Baseline, Week 26, Week 52, Week 78 ]
  Ambulatory status was evaluated using walking ability scale in polyneuropathy disability score. The ambulatory status was evaluated as: 0=Good, 1=Sensory disturbances in the feet but able to walk without difficulty, 2=Some difficulties with walking but can walk without aid, 3a=Able to walk with 1 stick or crutch, 3b=Able to walk with 2 sticks or crutches, 4=Not ambulatory, confined to a wheelchair or bedridden.
• Number of Participants With Transthyretin (TTR) Stabilization at Week 26, Week 52, and Week 78 Compared With Baseline as Measured by a Validated Immunoturbidimetric Assay [ Time Frame: Baseline, Week 26, Week 52, Week 78 ]
  TTR tetramer was assessed using a validated immunoturbidimetric assay. The TTR tetramer level for each plasma sample was measured before and after urea denaturation. The Fraction of Initial (FOI) tetramer concentration is the ratio of the measured TTR tetramer concentration after denaturation to the measured TTR tetramer concentration before denaturation. TTR tetramer stabilization is based on the difference between the on-treatment FOI and the baseline FOI expressed as a percentage of the baseline FOI. A patient who has the "TTR stabilization" is defin
  
  

  Original Secondary Outcome:

  • Change from baseline on the following scales: Neuropathy Impairment Score;QOL;"Σ7 NTs NDS" as measured by nerve conduction studies (NCS), vibration detection threshold (VDT) and heart rate response to deep breathing (HRDB); [ Time Frame: 3 years ]
  • Change from baseline on the following scales: "Σ3 NTSF NDS" as measured by cooling and heat pain thresholds utilizing CASE IV and heart rate response to deep breathing (HRDB); mBMI; Ambulatory status. [ Time Frame: 3 years ]
  • Transthyretin (TTR) stabilization at each follow up visit after Week 8. [ Time Frame: 3 years ]
  • Blood samples for determination of plasma levels of tafamidis will be collected at Baseline and during the visits at Week 2. [ Time Frame: 2 weeks ]
  • Blood samples for determination of plasma levels of tafamidis will be collected at Week 4. [ Time Frame: 4 weeks ]
  • Blood samples for determination of plasma levels of tafamidis will be collected Week 8. [ Time Frame: 8 weeks ]
  • Blood samples for determination of plasma levels of tafamidis will be collected at Week 26. [ Time Frame: 26 weeks ]
  • Blood samples for determination of plasma levels of tafamidis will be collected at Week 52. [ Time Frame: 52 weeks ]
  • Blood samples for determination of plasma levels of tafamidis will be collected at Week 78. [ Time Frame: 78 weeks ]
  • Blood samples for determination of plasma levels of tafamidis will be collected at End of study. [ Time Frame: 3 years ]

  
  
  Information By: Pfizer
  

  Dates:
  Date Received: September 13, 2011
  Date Started: November 2011
  Date Completion:
  Last Updated: August 10, 2015
  Last Verified: August 2015
  

  

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