A Study to Learn More About the Change in the Blood Levels of Transthyretin When Participants With Transthyretin Amyloidosis With Cardiomyopathy Switch From Tafamidis to Acoramidis
ACO-SWITCH
A Prospective, Single-arm, Phase 4 Study to Evaluate the Course of Serum Transthyretin (TTR) Level With Acoramidis in Adult Patients With Variant or Wild-type Transthyretin Amyloidosis With Cardiomyopathy (ATTR-CM) Previously Treated With Tafamidis
2 other identifiers
interventional
50
4 countries
10
Brief Summary
Transthyretin (TTR) is a protein made by the liver that helps transport thyroid hormone and vitamin A in the blood. In some people, this protein breaks down and forms harmful clumps called amyloid. TTR amyloid gets deposited in the heart wall and stops it from pumping blood properly, which may lead to heart failure. The breakage in TTR protein can be age-related (wild-type ATTR-CM), or genetic (variant ATTR-CM). The study drug, acoramidis, works by attaching itself to the TTR protein, making TTR more stable and less likely to break down and form amyloid (clumps). This helps to slow down the progression of the disease, improve heart function, and increase the TTR levels in the blood. Acoramidis is an approved treatment for wild-type or variant ATTR-CM in Europe and the United States. Tafamidis is another drug that stabilizes TTR and prevents it from breaking down. In this study, acoramidis will be studied in participants with ATTR--CM who were previously treated with tafamidis. The main purpose of this study is to assess the change in blood TTR levels after participants are switched from tafamidis to acoramidis. This will be studied to understand if acoramidis causes an increase in blood TTR levels beyond the levels achieved with tafamidis. For this, the researchers will measure the change in the levels of TTR protein in participants' blood after 6 months of the treatment with acoramidis, or earlier if a participant stops the treatment before reaching that six-month mark. All participants will continue taking tafamidis during the screening period. In the treatment period of the study, participants will take acoramidis as two tablets twice daily by mouth, for up to 6 months. At the start of this study, the study doctors will review each participant's medical history and check their overall health. The study doctors will perform electrocardiograms (ECG), and measure blood pressure and heart rate. Researchers will also take blood and urine samples from the participants to measure levels of TTr, NT-proBNP, hs-TnT, hs-CRP, RBP4, eGFR, creatinine, cystatin-C, UACR, and TSH at the start of the study, and at various time points thereafter (during the study) to assess heart, kidney and thyroid function. There will be a total of 9 study check-ins. Participants will visit the study site twice: at screening and at the end of treatment period. A study nurse will visit the participant's home 6 times, at the start of treatment, Weeks 1, 2, 3 and 4, then again at 3 months. The final check-in will be done by phone. The study doctors will monitor the health of the participants regularly for any medical problems during follow-up visits. Participants will know the treatment they will receive during the study. Each participant could be in the study for about 8 months.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P25-P50 for phase_4
Started Feb 2026
10 active sites
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
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Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
December 11, 2025
CompletedFirst Posted
Study publicly available on registry
December 22, 2025
CompletedStudy Start
First participant enrolled
February 13, 2026
CompletedPrimary Completion
Last participant's last visit for primary outcome
July 15, 2027
ExpectedStudy Completion
Last participant's last visit for all outcomes
July 15, 2027
June 8, 2026
June 1, 2026
1.4 years
December 11, 2025
June 5, 2026
Conditions
Keywords
Outcome Measures
Primary Outcomes (1)
Change in serum TTR level from baseline to month 6 or premature discontinuation of treatment
TTR = Transthyretin
From baseline to month 6 or premature discontinuation of treatment
Secondary Outcomes (15)
Serum TTR level at baseline, week 1, 2, 3, 4 and at month 3.
At baseline, week 1, 2, 3, 4 and at month 3
Number of participants with TEAEs and serious TEAEs
From the first administration of study drug until 30 days after the last dose of study drug or end of study, whatever occurs first
Change from baseline to month 6 of NT-proBNP
From baseline to month 6
Change from baseline to month 6 of hs-TnT
From baseline to month 6
Change from baseline to month 6 of hs-CRP
From baseline to month 6
- +10 more secondary outcomes
Study Arms (1)
Acoramidis
EXPERIMENTALParticipants will receive acoramidis 712 mg orally BID
Interventions
356 mg film-coated tablets. The recommended dose of acoramidis is 712 mg (two tablets, 356 mg) orally, twice daily, corresponding to a total daily dose of 1424 mg.
Eligibility Criteria
You may qualify if:
- Participants must be 18 to 90 years of age inclusive, at the time of signing the informed consent.
- Diagnosis of ATTR-CM; disease defining examination, i.e., Single Photon Emission Computed Tomography (SPECT) or SPECT/Computed Tomography (CT) or biopsy, within 24 months prior to Visit 1 (V1).
- Participants must currently be treated with tafamidis and have used tafamidis for at least the previous 3 months prior to V1 and have adhered to tafamidis therapy.
- New York Heart Association (NYHA) class ≤ II at V1.
- Estimate glomerular filtration rate (eGFR) ≥ 30 mL/min/1.73m\^2 at V1.
- N-terminal pro-B-type Natriuretic Peptide (NT-proBNP) \> 300 and ≤ 7000 pg/mL at V1.
You may not qualify if:
- Prior liver or heart transplantation or planned within the next 12 months.
- Current or planned use of ventricular assist device.
- Active cancer or other disease that decreases the life expectancy to less than one year.
- Heart failure due to ischemic heart disease.
- Myocardial infarction, cardiovascular (CV) surgery, or unstable angina within the last 90 days prior to V1.
- Confirmed diagnosis of light-chain amyloidosis.
- Dialysis or severe renal impairment as reflected by Urinary Albumin Creatinine Ratio (UACR) \> 300 mg/g at V1.
- Major surgery 90 days prior to V1.
- Recent initiation of Sodium-Glucose-Cotransporter-2 inhibitors (SGLT2i) within 3 months before V1.
- Initiation of treatment with a diuretic or increase in diuretic dose within 3 months before V1.
- Treatment with calcium channel blockers (e.g., verapamil, diltiazem) or digitalis.
- Recent CV hospitalization within 3 months before V1.
- Known hypersensitivity to acoramidis or to any of the excipients.
- A condition that, as judged by the investigator, would preclude compliance with the study protocol, such as a history of substance abuse, alcoholism, or a psychiatric condition.
- Known or suspected liver disorder and bile secretion/flow (cholestasis, also history of it).
- +1 more criteria
Contact the study team to confirm eligibility.
Sponsors & Collaborators
- Bayerlead
Study Sites (10)
Universitätsklinikum St. Pölten - Lilienfeld - Klinische Abteilung für Innere Medizin 3
Sankt Pölten, Lower Austria, 1210, Austria
Medizinische Universität Wien- Universitätsklinik für Innere Medizin II, Klinische Abteilung für Kardiologie
Vienna, State of Vienna, 1090, Austria
Klinik Favoriten - 5.Medizinische Abteilung-Kardiologie
Vienna, State of Vienna, 1100, Austria
Klinik Ottakring - 3. Medizinische Abteilung mit Kardiologie, internistischer Intensivmedizin und Ambulanz
Vienna, State of Vienna, 3500, Austria
Medizinische Universität Graz- Klinische Abteilung für Kardiologie
Vienna, Styria, 1030, Austria
Krankenhaus St. Josef Braunau | Innere Medizin I
Braunau am Inn, Upper Austria, 5280, Austria
AZ St-Jan Brugge-Oostende A.V.
Bruges, 8000, Belgium
Hôpital Erasme/Erasmus Ziekenhuis
Brussels, 1070, Belgium
KVZ Kardiovaskulaeres Zentrum Darmstadt GmbH
Darmstadt, Hesse, 64287, Germany
Oslo Universitetssykehus HF, Rikshospitalet
Oslo, 0424, Norway
MeSH Terms
Interventions
Central Study Contacts
Study Design
- Study Type
- interventional
- Phase
- phase 4
- Allocation
- NA
- Masking
- NONE
- Purpose
- TREATMENT
- Intervention Model
- SINGLE GROUP
- Sponsor Type
- INDUSTRY
- Responsible Party
- SPONSOR
Study Record Dates
First Submitted
December 11, 2025
First Posted
December 22, 2025
Study Start
February 13, 2026
Primary Completion (Estimated)
July 15, 2027
Study Completion (Estimated)
July 15, 2027
Last Updated
June 8, 2026
Record last verified: 2026-06
Data Sharing
- IPD Sharing
- Will not share
Currently, there is no established plan for the sharing of Individual Patient Data (IPD) from this study. The availability of this study's data will later be determined according to Bayer's commitment to the EFPIA/PhRMA 'Principles for responsible clinical trial data sharing.' This pertains to the scope, timepoint, and process of data access. As such, Bayer commits to considering requests from qualified researchers for patient- / study-level clinical trial data, and documents from clinical trials involving medicines and indications approved in the US and EU. However, this commitment does not reflect an active IPD sharing plan. This applies to data on new medicines and indications that have been approved by the EU and US regulatory agencies on or after January 01, 2014. Researchers can use www.vivli.org to request access to IPD and documents from clinical studies to conduct research. Information on Bayer's criteria for listing studies is provided in the member section of the portal.