This Study Tests Empagliflozin in Patients With Chronic Heart Failure With Reduced Ejection Fraction (HFrEF). The Study Looks at How Far Patients Can Walk in 6 Minutes and at Their Heart Failure Symptoms

Change from baseline to week 12 in exercise capacity as measured by the distance walked in 6 minutes in standardised conditions. If repeated 6MWT measurements were available for the same day, the longest distance was used for analysis. Change from baseline was defined as the distance walked in 6 minutes at week 12 minus the baseline value. Baseline value was defined as the last available measurement before start of treatment with randomised study medication. If a participant was present at the visit at week 12 but did not perform the 6MWT, the participant was evaluated as having walked a distance of 0 meter. If no value was available for week 12, an imputed value was used. Patients with missing week 12 data who had no clinical event were ranked below any patient with non-missing data, but above the patients who had clinical events. Patients who died before week 12 were ranked below the patients in all categories above.

Change from baseline in KCCQ-TSS was defined as the endpoint value at week 12 minus the last available measurement before start of treatment with randomised study medication. The KCCQ is 23 item self-administered questionnaire and comprises 7 domains: physical limitation, symptom frequency, symptom burden, symptom stability, social limitation, self-efficacy and quality of life. Additionally 3 summary scores exist: TSS, clinical summary score, and overall summary score. The scores of the KCCQ domains and summary scores range from 0 to 100, with higher score indicating better outcome. If no questionnaire was available at week 12, an imputed value was used. Patients with missing week 12 data who had no clinical event were ranked below any patient with non-missing data, but above the patients who had clinical events. Patients who died before week 12 were ranked below the patients in all categories above. If no questionnaire was available at baseline, change from baseline was not imputed.

Change from baseline in CHQ-SAS was defined as the endpoint value at week 12 minus the last available endpoint value before start of treatment with randomised study medication. The CHQ-SAS evaluates 3 domains: dyspnoea, fatigue, and emotional function. Scores of the domains range from 1 to 7, with higher score indicating better quality of life. If no questionnaire was available at week 12, an imputed value was used. Patients with missing week 12 data who had no clinical event were ranked below any patient with non-missing data, but above the patients who had clinical events. Patients who died before week 12 were ranked below the patients in all categories above. If no questionnaire was available at baseline, change from baseline was not imputed.

Change from baseline to week 6 in exercise capacity as measured by the distance walked in 6 minutes in standardised conditions. Change from baseline was defined as the distance walked in 6 minutes at week 6 minus the baseline value. Baseline value was defined as the last available measurement before start of treatment with randomised study medication.

If a participant was present at the visit at week 6 but did not perform the 6MWT, the participant was evaluated as having walked a distance of 0 meter. If no value was available for week 6, an imputed value was used.

Change from baseline to week 12 in Clinical Congestion score is defined as the score-value at week 12 minus the score-value at baseline. Baseline value was defined as the last available measurement before start of treatment with randomised study medication. The Clinical Congestion Score (summary score) is based on 3 items: orthopnoea, jugular venous distention (JVD) and oedema. Each item was assessed through a 4-measure questionnaire, which was further converted to a standardised 4-point scale ranging from 0 to 3, with 0 indicating no or fewer symptoms and 3 indicating continous or more symptoms. If at least 2 of the 3 items are not missing, the summary score is calculated as: (average over items JVD, orthopnea and oedema actually answered)*3. The summary score range from 0 to 9, with lower value indicating better health, and higher value indicating worse health. Mean is adjusted mean.

Change from baseline to week 12 in PGI-S of Heart Failure Symptoms. The Patient Global Impression of Severity (PGI-S) of Heart Failure Symptoms is a 1-item questionnaire to assess the patient's impression of symptoms severity, specifically: shortness of breath, fatigue and swelling. The PGI-S asks the Patient to choose one response that best describes how his/her heart failure symptoms, specifically: shortness of breath, fatigue and swelling are now on a 5-point scale, ranging from 'Not at all' (1) to 'Very severe' (5). Number of participants by change in score are reported. Change in score was defined as the number of categories improved/deteriorated from baseline to week 12.

Change from baseline to week 12 in Patient Global Impression of Severity (PGI-S) of dyspnoea. The PGI-S of Dyspnoea is a 1-item questionnaire designed to assess the participant´s impression of symptom severity, specifically dyspnoea. The PGI-S item asks the participant to choose one response that best describes how his/her dyspnoea is now on a 5-point scale, ranging from 'Not at all' (1) to 'Very severe' (5). Number of participants by change in score are reported. Change in score was defined as the number of categories improved/deteriorated from baseline to week 12.

The Patient Global Impression of Change (PGI-C) in Heart Failure Symptoms is a 1-item questionnaire to assess the patient's impression of change in heart failure symptoms, specifically: shortness of breath, fatigue, and swelling. The PGI-C asks the patient to choose one Response that best describes the overall change (if any) in his/her heart failure symptoms, specifically: shortness of breath, fatigue, and swelling since he/she started taking the study medication on a 7- category scale ranging from 'Very much better' (+3) to 'Very much worse' (-3).

The PGI-C in Dyspnoea is a 1-item questionnaire designed to assess the patient's Impression of change in dyspnoea. The PGI-C asks the patient to choose one response that best describes the change (if any) in his/her shortness of breath when performing usual activities since he/she started taking the study medication on a 7-category scale ranging from 'Very much better' (+3) to 'Very much worse' (-3).

Relative change from baseline to week 12 in N-terminal pro-brain natriuretic peptide (NTproBNP). Relative change from baseline is expressed as ratio of week 12 to baseline. Baseline value was defined as the mean of all available measurements from the screening visit until start of treatment with randomised study medication.