Tamibarotene for HFpEF: see if this drug helps heart failure with preserved ejection fraction

Inclusion Criteria:

* 1\. Patients who have been diagnosed with heart failure at least 12 weeks prior to providing informed consent and are classified as NYHA Class II to IV at screening.
* 2\. Patients with LVEF of 50% or more as determined by echocardiography at screening.
* 3\. Patients with an NT-proBNP level of 300 pg/mL or more at screening (or 600 pg/mL or more for patients with atrial fibrillation at screening).
* 4\. Patients have evidence of structural heart disease (left atrial enlargement and/or left ventricular hypertrophy) based on echocardiography at screening, or who have a history of hospitalization for heart failure within 12 months prior to providing informed consent.
* 5\. Patients receiving any of the following medications whose dosage regimen has remained unchanged for at least 4 weeks prior to the initiation of investigational product administration:

  ・Diuretics,SGLT2 inhibitors, ARNIs, ARBs, ACE inhibitors, MRAs, beta-blockers, digitalis preparations, HCN channel blockers, Soluble guanylate cyclase stimulators
* 6\. Patients with eGFR of 30 mL/min/1.73 m² or more at screening.
* 7\. Patients with a BMI of less than 45 kg/m² at screening.
* 8\. Patients with a systolic blood pressure of 160 mmHg or less and a diastolic blood pressure of 100 mmHg or less at screening, whose antihypertensive medication regimen has remained unchanged for at least 4 weeks prior to the initiation of investigational product administration.
* 9\. Patients who agree to comply with the applicable requirement(s) below:
* 1\) For female patients of childbearing potential, willingness to use contraceptionii from 30 days before the initiation of investigational product administration until 2 years after the end of investigational product administration.
* 2\) For male patients with partners of childbearing potential, willingness to use contraceptionii from the initiation of investigational product administration until 6 months after the end of investigational product administration, and to refrain from sperm donation during this period.
* 10\. Patients who are at least 26 years of age at the time informed consent is obtained.
* 11\. Patients who have voluntarily provided written informed consent after receiving adequate information about the study.

Exclusion Criteria:

* 1\. Patients diagnosed with acute heart failure, atrial fibrillation, or atrial flutter with a resting heart rate greater than 110 bpm within 4 weeks prior to enrollment.
* 2\. Patients with a history of myocardial infarction or unstable angina within 12 weeks prior to enrollment.
* 3\. Patients with chronic heart failure attributable to cardiac amyloidosis, glycogen storage disease, hypertrophic cardiomyopathy, active myocarditis, mitochondrial cardiomyopathy, cardiac sarcoidosis, arrhythmogenic right ventricular cardiomyopathy, constrictive endocarditis, cardiac tamponade, untreated severe valvular heart disease, congenital heart disease, or other similar conditions.
* 4\. Patients who have undergone PCI, CABG, valvuloplasty, valve replacement surgery, catheter ablation, implantation of an ICD, CRT, or any other cardiac surgery within 12 weeks prior to enrollment, or who are expected to require any of these procedures during the study period.
* 5\. Patients who have received mechanical circulatory support within 12 weeks prior to enrollment.
* 6\. Patients with a history of stroke or transient ischemic attack within 12 weeks prior to enrollment.
* 7\. Patients with evidence of increased bleeding tendency or coagulation abnormalities, including thromboembolic disorders or hemorrhagic disorders (except for patients whose condition is adequately controlled with anticoagulants, antiplatelet agents, or similar medications).
* 8\. Patients with pulmonary diseases, including primary pulmonary hypertension, chronic thromboembolic pulmonary hypertension, COPD, or interstitial lung disease.
* 9\. Patients with hepatic impairment (AST 100 IU/L or more, or ALT 100 IU/L or more).
* 10\. Patients with LDL cholesterol 180 mg/dL or more, or TG (non-fasting)300 mg/dL or more at screening.
* 11\. Patients receiving maintenance dialysis or those considered likely to require initiation of dialysis within 1 year.
* 12\. Patients with type 1 diabetes mellitus.
* 13\. Patients with hemoglobin less than 9.0 g/dL at screening.
* 14\. Patients with malignant neoplasms.
* 15\. Patients whose life expectancy is anticipated to be less than 1 year.
* 16\. Patients currently receiving vitamin A preparations or regularly taking supplements containing vitamin A.
* 17\. Patients with hypervitaminosis A.
* 18\. Breastfeeding female patients (except those who agree to discontinue breastfeeding during the investigational product treatment period and for 6 months after the last dose of investigational product).
* 19\. Pregnant female patients or female patients with a positive pregnancy test result (female patients of childbearing potential who have had menstruation within 12 months prior to enrollment must undergo pregnancy testing; female patients for whom the possibility of pregnancy cannot be excluded, including those with amenorrhea for more than 12 months due to reasons such as chemical menopause, must also undergo pregnancy testing).
* 20\. Patients with a history of hypersensitivity or anaphylactic reaction to any component of the investigational product.
* 21\. Patients who have participated in, or are currently participating in, a clinical trial (observational clinical researches are permitted) within 4 weeks prior to enrollment.
* 22\. Patients whom the Principal Investigator or Sub-Investigator considers unsuitable for participation in this study.