The annualized change in eGFR will be calculated from the Chronic Kidney Disease Epidemiology Collaboration eGFR creatinine equation refit without the race variable (CKD-EPIcr_R) equation for serum creatinine from baseline (mean of 3 eGFR determinations obtained during Screening and Placebo Run-in Periods [Visits 1a/1b (if required), Visit 2, and Visit 3]) to final assessment (mean of 3 eGFR determinations obtained during Follow-up Period I or, for participants who discontinue treatment prior to Visit 22, during the Follow-up Period 8 to 28 days following study drug treatment discontinuation).

Efficacy data were not analyzed as only 5 participants were randomized, and all 5 participants were prematurely terminated from the study drug by the sponsor less than 1 month following randomization. One month after randomization was the first scheduled post-randomization visit during which efficacy parameters would have been collected.

The annualized change in eGFR will be calculated from the CKD-EPIcr_R equation for serum creatinine from baseline (mean of 3 eGFR determinations obtained during obtained during Follow-up Period I) to final assessment (mean of 3 eGFR determinations obtained during Follow-up Period II or, for participants who discontinue treatment prior to Visit 43, during the Follow-up Period 8 to 28 days following study drug treatment discontinuation).

Efficacy data were not analyzed as only 5 participants were randomized, and all 5 participants were prematurely terminated from the study drug by the sponsor less than 1 month following randomization. One month after randomization was the first scheduled post-randomization visit during which efficacy parameters would have been collected. The study terminated prior to any participants entering Part 2 of study.

Number of participants randomized to lixivaptan with serum ALT levels >3 × the ULN compared to those randomized to placebo. The normal range of ALT was defined as 0-33 or 0-44 U/L, depending on the lab used.

All participants who entered the Double-blind Randomized Treatment Period.

Number of participants randomized to lixivaptan with serum ALT levels >3 × ULN compared to those randomized to placebo. The normal range of ALT was defined as 0-33 or 0-44 U/L, depending on the lab used.

The study terminated prior to any participants entering Part 2 of study.

Annualized rate of change (slope) in eGFR for serum creatinine, based on all eGFR determinations from baseline to all visits with on-treatment eGFR values during the Double-blind, Randomized Treatment Period. The baseline value will be calculated as the mean of 3 eGFR determinations obtained during Screening and Placebo Run-in Periods (Visits 1a/1b [if required], Visit 2, and Visit 3).

Efficacy data were not analyzed as only 5 participants were randomized, and all 5 participants were prematurely terminated from the study drug by the sponsor less than 1 month following randomization. One month after randomization was the first scheduled post-randomization visit during which efficacy parameters would have been collected.

Annualized rate of change (slope) in eGFR for serum creatinine, based on all eGFR determinations from baseline to all visits with on-treatment eGFR values during the Maintenance Treatment Period. The baseline value will be calculated as the mean of 3 eGFR determinations obtained during obtained during Follow-up Period I.

Efficacy data were not analyzed as only 5 participants were randomized, and all 5 participants were prematurely terminated from the study drug by the sponsor less than 1 month following randomization. One month after randomization was the first scheduled post-randomization visit during which efficacy parameters would have been collected. The study terminated prior to any participants entering Part 2 of study.

Annualized percent change in htTKV, determined by magnetic resonance imaging (MRI), from baseline (obtained at Screening [Visit 1a]) to the end of Follow-up Period I.

Efficacy data were not analyzed as only 5 participants were randomized, and all 5 participants were prematurely terminated from the study drug by the sponsor less than 1 month following randomization. One month after randomization was the first scheduled post-randomization visit during which efficacy parameters would have been collected.

Annualized percent change in htTKV, determined by MRI from baseline (obtained at Visit 25/Week 56) to the end of Follow-up Period II.

Efficacy data were not analyzed as only 5 participants were randomized, and all 5 participants were prematurely terminated from the study drug by the sponsor less than 1 month following randomization. One month after randomization was the first scheduled post-randomization visit during which efficacy parameters would have been collected. The study terminated prior to any participants entering Part 2 of study.

Number of participants with TEAEs during the Lixivaptan Titration Period.

All participants entering the Lixivaptan Titration Period.

Number of participants with TEAEs by treatment group after Randomization (Double-blind Randomized Treatment Period and Follow-up Period I)

All participants who were randomized.

Number of participants with TEAEs by treatment cohort during Part 2 (Lixivaptan Re-titration Period, Maintenance Treatment Period, and Follow-up Period II).

All participants were prematurely terminated from the study drug by the sponsor less than 1 month following randomization; none proceeded to Part 2 of the study.

Number of participants with clinical laboratory findings (clinical chemistry, hematology and urinalysis) recorded during the Lixivaptan Titration Period and considered to be potentially clinically important.

All participants entering the Lixivaptan Titration Period.

Number of participants with clinical laboratory findings (clinical chemistry, hematology and urinalysis) recorded after Randomization (Double-blind Randomized Treatment Period and Follow-up Period I) and considered to be potentially clinically important, by treatment group.

All participants who were randomized.

Number of participants with clinical laboratory findings (clinical chemistry, hematology and urinalysis) recorded during Part 2 (Lixivaptan Re-titration Period, Maintenance Treatment Period, and Follow-up Period II) and considered to be potentially clinically important, by treatment cohort.

All participants were prematurely terminated from the study drug by the sponsor less than 1 month following randomization; none proceeded to Part 2 of the study.

Number of participants with vital signs findings (heart rate, diastolic and systolic blood pressure, weight) recorded during the Lixivaptan Titration Period and considered to be potentially clinically important.

All participants entering the Lixivaptan Titration Period.

Number of participants with vital signs findings (heart rate, diastolic and systolic blood pressure, weight) recorded after Randomization (Double-blind Randomized Treatment Period and Follow-up Period I) and considered to be potentially clinically important, by treatment group.

All participants who were randomized.

Number of participants with vital signs findings (heart rate, diastolic and systolic blood pressure, weight) recorded during Part 2 (Lixivaptan Re-titration Period, Maintenance Treatment Period, and Follow-up Period II) and considered to be potentially clinically important, by treatment cohort.

All participants were prematurely terminated from the study drug by the sponsor less than 1 month following randomization; none proceeded to Part 2 of the study.

Number of participants with ECG findings recorded during the Lixivaptan Titration Period and considered to be potentially clinically important (defined as a QT interval corrected for heart rate according to Fridericia's formula [QTcF] ≥ 450 msec).

All participants entering the Lixivaptan Titration Period.

Number of participants with ECG findings recorded after Randomization (Double-blind Randomized Treatment Period and Follow-up Period I) and considered to be potentially clinically important (defined as a QTcF ≥ 450 msec), by treatment group.

All participants who were randomized.

Number of participants with ECG findings recorded during Part 2 (Lixivaptan Re-titration Period, Maintenance Treatment Period, and Follow-up Period II) and considered to be potentially clinically important (defined as a QTcF ≥ 450 msec), by treatment cohort.

All participants were prematurely terminated from the study drug by the sponsor less than 1 month following randomization; none proceeded to Part 2 of the study.