A Study to Examine the Clinical Effectiveness of Tafamidis in Patients With Mixed Phenotype Hereditary Transthyretin Amyloidosis

NCT05139680 | Completed Results

• 1 other identifier: B3461099
• Study Type: observational
• Target: 10
• Locations: 1 country
• Sites: 1

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.

Conditions

Hereditary Transthyretin Amyloidosis (ATTRv) Cardiomyopathy (CM), Mixed Phenotype

Keywords

transthyretin; amyloidosis; cardiomyopathy; tafamidis; polyneuropathy; progression

Outcome Measures

Primary Outcomes (3)

• Neurologic Disease Progression: Number of Participants According to Muscle Weakness Assessment by Neuropathy Impairment Score (NIS) Subscale Score

  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.

  Pre-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: Number of Participants According to Walking Capacity Assessment by Polyneuropathy Disability (PND) Score

  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.

  Pre-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: Number of Participants According to Muscle Strength Assessment by Medical Research Council (MRC) Scale

  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.

  Pre-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)

Secondary Outcomes (1)

• 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)

Study Arms (1)

Patients with mixed phenotype ATTRv-CM

Hereditary ATTR-CM patients presenting with mixed phenotype

Drug: tafamidis

Interventions

tafamidis DRUG

80 or 61 milligrams (mg)

Also known as: Vyndaqel, Vyndamax

Patients with mixed phenotype ATTRv-CM

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

The study will include patients with mixed-phenotype ATTRv-CM who are treated in the Amyloidosis Program at MedStar.

You may qualify if:

• 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

You may not qualify if:

• 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)

Sponsors & Collaborators

• Pfizer: lead

Study Sites (1)

Pfizer

New York, New York, 10017, United States

Location

Related Publications (1)

• Streicher N, Amass L, Wang R, Stephens JM, LeMasters T, Raina R, Merrill E, Sheikh FH. Real-World Effectiveness of High-Dose Tafamidis on Neurologic Disease Progression in Mixed-Phenotype Variant Transthyretin Amyloid Cardiomyopathy. Cardiol Ther. 2024 Jun;13(2):359-368. doi: 10.1007/s40119-024-00362-9. Epub 2024 Mar 23.

  PMID: 38521883 DERIVED

Related Links

• To obtain contact information for a study center near you, click here.

MeSH Terms

Conditions

Amyloidosis, Hereditary, Transthyretin-Related; Cardiomyopathies; Amyloidosis; Polyneuropathies; Disease Progression

Interventions

tafamidis

Condition Hierarchy (Ancestors)

Heart Diseases; Cardiovascular Diseases; Proteostasis Deficiencies; Metabolic Diseases; Nutritional and Metabolic Diseases; Peripheral Nervous System Diseases; Neuromuscular Diseases; Nervous System Diseases; Disease Attributes; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Results Point of Contact

• Title: Pfizer ClinicalTrials.gov Call Center
• Organization: Pfizer Inc.

ClinicalTrials.gov_Inquiries@pfizer.com

1-800-718-1021

Study Officials

• Pfizer CT.gov Call Center

  Pfizer

  STUDY DIRECTOR

Publication Agreements

• PI is Sponsor Employee: No
• Restriction Type: OTHER
• Restrictive Agreement: Yes

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: RETROSPECTIVE
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: November 17, 2021
• First Posted: December 1, 2021
• Study Start: March 8, 2023
• Primary Completion: May 19, 2023
• Study Completion: May 19, 2023
• Last Updated: September 19, 2024
• Results First Posted: September 19, 2024

Record last verified: 2024-04

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)