Updated May 2026 · ClinicalTrials.gov

RECRUITINGPhase 4INTERVENTIONAL

Safety, Efficacy, and Pharmacokinetics of Tafamidis in Patients With Transthyretin-mediated Amyloidosis Post Orthotopic Heart Transplantation

Q: Who can participate in NCT05489523?

Eligibility for this trial depends on the specific inclusion and exclusion criteria set by the sponsor. The plain-English summary above translates the most important criteria into accessible language; the official clinical text is preserved in the collapsible section underneath. Whether you fit any specific trial is a medical decision your doctor needs to confirm — bring the trial information to your treating physician for a full review against your medical history.

Q: How do I contact the trial site for NCT05489523?

Contact information registered with ClinicalTrials.gov is shown in the sidebar of this page. Before reaching out, confirm with your treating physician that this trial is appropriate for your situation. The trial site will then walk you through the screening process to determine final eligibility.

Q: Is participating in a clinical trial safe?

Clinical trials in the United States are regulated by the FDA and overseen by Institutional Review Boards (IRBs) that review the protocol for safety. Risk varies by trial — Phase 1 studies test new treatments in humans for the first time, while Phase 3 trials use treatments that have already passed earlier safety screening. The informed consent document for any specific trial details the known risks and what to expect. Discuss those risks with your physician before deciding whether to participate.

Q: Where can I verify the data on this page?

Every detail on this page comes directly from the ClinicalTrials.gov API. Click "View on ClinicalTrials.gov" in the sidebar to see the official, unmodified record. The federal record is always authoritative; this page is a structured presentation with a plain-English eligibility translation. For background on how clinical trials are regulated, see the FDA drug approval process documentation.

An Open-label Study to Evaluate the Safety, Efficacy, and Pharmacokinetics of Tafamidis in Patients With Transthyretin-mediated Amyloidosis Post Orthotopic Heart Transplantation

Safety, Efficacy, and Pharmacokinetics of Tafamidis in Patients With Transthyretin-mediated Amyloidosis Post Orthotopic Heart Transplantation (NCT05489523) is a Phase 4 interventional studying Transthyretin Cardiac Amyloidosis, sponsored by University of Texas Southwestern Medical Center. RECRUITING as of the most recent ClinicalTrials.gov update. Talk to your doctor before contacting the trial site.

About This Trial

Transthyretin cardiac amyloidosis (ATTR-CA) is a relentlessly progressive disease that can progress to end stage heart failure, at which point recently approved transthyretin production silencing or structure stabilizing therapies provide no clinical benefit. For well-selected individuals, heart transplantation is an excellent therapeutic option to improve survival. Historically, concomitant liver transplantation has been used to halt the progression of non-cardiac transthyretin amyloidosis (ATTR) manifestations, especially for individuals with TTR genotypes associated with significant neuropathy. However, despite this, patients continue to experience progressive non-cardiac manifestations, particularly gastrointestinal and neuropathic, which can have a substantial influence on post-heart transplantation morbidity. Concomitant liver transplantation is also associated with substantial morbidity and its future therapeutic role is questionable with recently established therapies for ATTR. Therefore, there is a clear unmet need to determine the utility and safety of ATTR targeted therapies for patients with recent heart transplantation for end-stage ATTR-CA. The central hypothesis of this proposal is that in patients who have received a heart transplantation for end-stage ATTR-CA, tafamidis therapy will be efficacious and well-tolerated. We aim to determine the safety and efficacy of tafamidis in stable patients who have undergone heart or combined heart/liver transplantation for ATTR (wild-type or variant) cardiac amyloidosis. The proposed study will be a single-arm intervention clinical trial with tafamidis. Because of the efficacy of tafamidis for both variant ATTR-CA and wild-type ATTR-CA, there is no clinical equipoise for an inactive-comparator placebo arm. The primary endpoint of this study will be serial change in plasma transthyretin (TTR) levels from baseline to 12 months at 3-month intervals. The secondary endpoints of this study will include serial changes in neuropathy assessments, modified body mass indices, incident transplant-specific adverse events, and pharmacokinetics of tafamidis. Observations from this study will establish the role of tafamidis use for the management of ATTR in patients after transplantation for end-stage ATTR-CA.

What Stage of Research Is This?

Phase 4 studies happen after a treatment has been approved by the FDA. They monitor long-term safety, real-world effectiveness, and any rare side effects that only emerge in larger populations over longer periods. Phase 4 results sometimes lead to label changes, additional warnings, or — rarely — withdrawal of approval.

This trial is currently recruiting participants. The sponsor has registered the study with ClinicalTrials.gov as actively enrolling, which means new applicants who meet the eligibility criteria can be considered for screening. Trial status can change between updates — confirm current recruiting status with the study contact before traveling for a screening visit.

With a target enrollment of 25 participants, this is a small study — typical of early-phase research, rare-disease trials, or pilot studies designed to generate preliminary signal before a larger study is launched.

Who May Be Eligible (Plain English)

Who May Qualify: - Has received orthotopic heart transplantation for end-stage ATTRv or ATTRwt ≥12 months prior to screening. Concomitant hepatic and renal transplantation with adequate allograft function are included. - Has a stable immunosuppressive regimen and ≤ 10 mg of prednisone (or equivalent) at time of enrollment. - Has a Karnofsky performance status ≥ 70% Who Should NOT Join This Trial: - Has previously received inotersen within the past 180 days, patisiran within the past 90 days, tafamidis within the past 14 days, or diflunisal in the past 14 days. - Participating in a clinical trial for ATTR targeted therapies. - Has an estimated glomerular filtration rate (eGFR) ≤ 15 ml/min/1.73 m2 - Has known leptomeningeal or AL amyloidosis - Has active post-transplant lymphoproliferative disease - Excluding non-melanomatous skin cancers, has an active malignancy. - Has active infection with hepatitis B, hepatitis C, human weakened immune system virus, or cytomegalovirus (CMV). For CMV, donor/ recipient exposure status and prior treated CMV disease on stable doses of antiviral therapies are not excluded. - Has cardiac allograft dysfunction defined by left ventricular ejection fraction (LVEF) \<50% by echocardiogram within the past 3 months - Has been treated for acute cellular or antibody mediated rejection in the past 3 months - Has criteria to meet International Society for Heart and Lung Transplantation standardized nomenclature for severe coronary allograft vasculopathy ("ISHLT CAV3") Always talk to your doctor about whether this trial is right for you.

These are translations of the protocol\'s inclusion and exclusion criteria, simplified for patients and caregivers. The original clinical text appears below. Eligibility is ultimately confirmed by the trial site\'s screening process — this summary is a starting point for a conversation with your doctor, not a final determination.

Original Eligibility Criteria

View original clinical language

Inclusion Criteria: * Has received orthotopic heart transplantation for end-stage ATTRv or ATTRwt ≥12 months prior to screening. Concomitant hepatic and renal transplantation with adequate allograft function are included. * Has a stable immunosuppressive regimen and ≤ 10 mg of prednisone (or equivalent) at time of enrollment. * Has a Karnofsky performance status ≥ 70% Exclusion Criteria: * Has previously received inotersen within the past 180 days, patisiran within the past 90 days, tafamidis within the past 14 days, or diflunisal in the past 14 days. * Participating in a clinical trial for ATTR targeted therapies. * Has an estimated glomerular filtration rate (eGFR) ≤ 15 ml/min/1.73 m2 * Has known leptomeningeal or AL amyloidosis * Has active post-transplant lymphoproliferative disease * Excluding non-melanomatous skin cancers, has an active malignancy. * Has active infection with hepatitis B, hepatitis C, human immunodeficiency virus, or cytomegalovirus (CMV). For CMV, donor/ recipient exposure status and prior treated CMV disease on stable doses of antiviral therapies are not excluded. * Has cardiac allograft dysfunction defined by left ventricular ejection fraction (LVEF) \<50% by echocardiogram within the past 3 months * Has been treated for acute cellular or antibody mediated rejection in the past 3 months * Has criteria to meet International Society for Heart and Lung Transplantation standardized nomenclature for severe coronary allograft vasculopathy ("ISHLT CAV3")

Treatments Being Tested

DRUG

Tafamidis 61 MG

Tafamidis 61 mg by mouth daily for 12 months

Locations (4)

Trial sites listed on ClinicalTrials.gov for this study. Site activation status can vary — confirm with the specific site before traveling for a screening visit.

Cedars-Sinai

Beverly Hills, California, United States

Columbia University Medical Center

New York, New York, United States

Cleveland Clinic

Cleveland, Ohio, United States

UT Southwestern Medical Center

Dallas, Texas, United States

How to Talk to Your Doctor About This Trial

Bring the printable summary of this trial — including the NCT ID (NCT05489523), the sponsor (University of Texas Southwestern Medical Center), and the key eligibility criteria — to your next appointment. Your doctor can review the inclusion and exclusion criteria against your medical history, lab values, and current treatments to assess whether you are likely to qualify. They can also help you weigh whether trial participation makes sense alongside your existing care plan.

Useful questions to walk through together: What does the trial protocol require beyond standard care? How long is the active treatment phase, and how long is follow-up? Are there study visits at sites I can reach? Who pays for the trial-specific procedures, and who pays for standard-of-care portions? See our 25 questions to ask about clinical trials guide for a more complete checklist.

Authoritative Sources

The official record for this trial lives on ClinicalTrials.gov — the federal registry maintained by the National Library of Medicine at NIH. For background on how this trial fits into the FDA approval pathway, see the FDA drug approval process. For oncology-specific guidance for patients considering trials, the National Cancer Institute publishes patient-oriented overviews. International trial registries are aggregated by the WHO ICTRP.

Frequently Asked Questions

What is the NCT05489523 clinical trial studying?

Who can participate in NCT05489523?

Eligibility for this trial depends on the specific inclusion and exclusion criteria set by the sponsor. The plain-English summary above translates the most important criteria into accessible language; the official clinical text is preserved in the collapsible section underneath. Whether you fit any specific trial is a medical decision your doctor needs to confirm — bring the trial information to your treating physician for a full review against your medical history.

How do I contact the trial site for NCT05489523?

Contact information registered with ClinicalTrials.gov is shown in the sidebar of this page. Before reaching out, confirm with your treating physician that this trial is appropriate for your situation. The trial site will then walk you through the screening process to determine final eligibility.

Is participating in a clinical trial safe?

Clinical trials in the United States are regulated by the FDA and overseen by Institutional Review Boards (IRBs) that review the protocol for safety. Risk varies by trial — Phase 1 studies test new treatments in humans for the first time, while Phase 3 trials use treatments that have already passed earlier safety screening. The informed consent document for any specific trial details the known risks and what to expect. Discuss those risks with your physician before deciding whether to participate.

Where can I verify the data on this page?

Every detail on this page comes directly from the ClinicalTrials.gov API. Click "View on ClinicalTrials.gov" in the sidebar to see the official, unmodified record. The federal record is always authoritative; this page is a structured presentation with a plain-English eligibility translation. For background on how clinical trials are regulated, see the FDA drug approval process documentation.

How This Page Is Built

Every field on this page is pulled directly from the ClinicalTrials.gov API v2 — no estimates, no proxies. The plain-English eligibility translation is generated from the original protocol text and reviewed for fidelity to the underlying clinical criteria. The original clinical text remains visible in the collapsible section above so users and clinicians can verify the translation. Read the full methodology for the data pipeline and known limitations.

Source: ClinicalTrials.gov API v2 record for NCT05489523. Maintained by the National Library of Medicine at NIH. Public domain. Cite as: "TrialFinderData. NCT05489523. Data: ClinicalTrials.gov."

Medical disclaimer: This page is informational, not medical advice. Talk to your doctor about whether a clinical trial is right for you.

Last updated 2026-05-08 · Data from ClinicalTrials.gov.