Sodium Glucose Co-transporter (SGLT) Inhibitors in Nonobstructive Hypertrophic Cardiomyopathy

Inclusion Criteria:

1. Age at least 18 years, both sexes

2. Provision of signed and dated informed consent form

3. Stated willingness to comply with all study procedures and availability for theduration of the study

4. Ability to take oral medication and be willing to adhere to the study intervention.

5. For females of reproductive potential: use of highly effective contraception for atleast 1 month prior to screening and agreement to use such a method during studyparticipation and for an additional 2 weeks after the end of administration of studydrug.

6. Diagnosis of HCM with NYHA Class II-III functional class or New York HeartAssociation (NYHA) Class I with peak VO2 < 90% on cardiopulmonary exercise stresstesting performed at Visit 1.

7. Left ventricular outflow tract gradient < 50 mmHg at rest, with valsalva, and withexercise.

8. Left ventricular ejection fraction > 50% by echocardiogram or cardiac MRI based onthe most recent assessment in the past year prior to screening and confirmed duringVisit 1 echocardiogram.

9. Stable medical therapy for at least 1 month prior to study enrollment.

Exclusion Criteria:

1. Receiving therapy with an SGLT2 inhibitor within 8 weeks prior to enrollment orprevious intolerance of an SGLT2 inhibitor

2. Type 1 diabetes mellitus

3. Age <18 years old

4. Pregnant or lactating women: Women of childbearing potential will undergo a urinepregnancy test during the screening visit.

5. Uncontrolled atrial fibrillation, as defined by a resting heart rate > 100 beats perminute at the time of the baseline assessment

6. Paroxysmal atrial fibrillation (Afib) or flutter with plans to attempt to restoresinus rhythm (with drug therapy, ablation, or DC cardioversion) during the studyperiod.

7. Unable to attain a respiratory exchange ratio of at least 1.05 on cardiopulmonaryexercise test (CPET) on the day of screening.

8. Septal reduction therapy within the previous 3 months.

9. Implantable cardio-defibrillator (ICD) implantation planned during the study period.

10. Implantation of a cardiac resynchronization therapy (CRT) device within 12 weeksprior to enrollment or intent to implant a CRT device during the study period

11. Hemoglobin < 10 g/dL

12. Estimated glomerular filtration rate (eGFR) < 25 mL/min/1.73m^2, or unstable orrapidly progressing renal disease at the time of randomization

13. Subject inability/unwillingness to exercise

14. Greater than moderate left sided valvular disease (mitral regurgitation, aorticstenosis, aortic regurgitation), moderate or greater mitral stenosis, or severeright-sided valvular disease based on baseline echo at the time of enrollment

15. Current angina due to clinically significant epicardial coronary disease, as perinvestigator judgment

16. Acute coronary syndrome or coronary intervention within the past 2 months

17. Primary pulmonary artery hypertension (WHO Group 1 Pulmonary Arterial Hypertension)

18. Clinically significant lung disease as defined by: Chronic Obstructive PulmonaryDisease meeting Stage III or greater GOLD criteria (FEV1<50% predicted), treatmentwith oral steroids within the past 6 months for an exacerbation of obstructive lungdisease, or current use of supplemental oxygen aside from nocturnal oxygen for thetreatment of obstructive sleep apnea.

19. Clinically-significant ischemia, as per investigator's judgement, on stress testingwithout either (1) subsequent revascularization, (2) an angiogram demonstrating theabsence of clinically significant epicardial coronary artery disease, as perinvestigator judgment; (3) a follow-up 'negative' stress test, particularly whenusing a more specific technique (i.e., a negative perfusion imaging test following a 'positive' ECG stress test)

20. Symptomatic bradycardia or second- or third-degree heart block, in the absence of apacemaker

21. Significant liver disease impacting synthetic function or volume control (ALT/AST > 3x ULN, Albumin < 3.0 g/dL)

22. Severe right ventricular dysfunction on baseline echocardiogram

23. Orthostatic blood pressure response to the transition from supine to standing (>20mmHg reduction in systolic blood pressure 2-3 minutes after standing)

24. Active participation in another study that utilizes an investigational agent (observational studies/registries allowed)

25. Any condition that, in the opinion of the investigator, will interfere with thecompletion of the study. This may include comorbid or psychiatric conditions thatmay impede successful completion of the protocol, or logistical concerns (e.g.inability to travel to the exercise unit).