John Ouyang

Tolvaptan in Patients with Autosomal Dominant Polycystic Kidney Disease

BACKGROUND The course of autosomal dominant polycystic kidney disease (ADPKD) is often associated with pain, hypertension, and kidney failure. Preclinical studies indicated that vasopressin V(2)-receptor antagonists inhibit cyst growth and slow the decline of kidney function. METHODS In this phase 3, multicenter, double-blind, placebo-controlled, 3-year trial, we randomly assigned 1445 patients, 18 to 50 years of age, who had ADPKD with a total kidney volume of 750 ml or more and an estimated creatinine clearance of 60 ml per minute or more, in a 2:1 ratio to receive tolvaptan, a V(2)-receptor antagonist, at the highest of three twice-daily dose regimens that the patient found tolerable, or placebo. The primary outcome was the annual rate of change in the total kidney volume. Sequential secondary end points included a composite of time to clinical progression (defined as worsening kidney function, kidney pain, hypertension, and albuminuria) and rate of kidney-function decline. RESULTS Over a 3-year period, the increase in total kidney volume in the tolvaptan group was 2.8% per year (95% confidence interval [CI], 2.5 to 3.1), versus 5.5% per year in the placebo group (95% CI, 5.1 to 6.0; P<0.001). The composite end point favored tolvaptan over placebo (44 vs. 50 events per 100 follow-up-years, P=0.01), with lower rates of worsening kidney function (2 vs. 5 events per 100 person-years of follow-up, P<0.001) and kidney pain (5 vs. 7 events per 100 person-years of follow-up, P=0.007). Tolvaptan was associated with a slower decline in kidney function (reciprocal of the serum creatinine level, -2.61 [mg per milliliter](-1) per year vs. -3.81 [mg per milliliter](-1) per year; P<0.001). There were fewer ADPKD-related adverse events in the tolvaptan group but more events related to aquaresis (excretion of electrolyte-free water) and hepatic adverse events unrelated to ADPKD, contributing to a higher discontinuation rate (23%, vs. 14% in the placebo group). CONCLUSIONS Tolvaptan, as compared with placebo, slowed the increase in total kidney volume and the decline in kidney function over a 3-year period in patients with ADPKD but was associated with a higher discontinuation rate, owing to adverse events. (Funded by Otsuka Pharmaceuticals and Otsuka Pharmaceutical Development and Commercialization; TEMPO 3:4 ClinicalTrials.gov number, NCT00428948.).

Vasopressin V2-Receptor Blockade With Tolvaptan in Patients With Chronic Heart Failure Results From a Double-Blind, Randomized Trial

Background—In this study, we evaluated the effects of tolvaptan (OPC-41061), a novel, oral, nonpeptide vasopressin V2-receptor antagonist in patients with chronic heart failure (CHF). Methods and Results—This was a double-blind study investigating the effects of three doses of tolvaptan and placebo in patients with CHF. After a run-in period, 254 patients were randomly assigned to placebo (n=63) or tolvaptan [30 mg (n=64), 45 mg (n=64), or 60 mg (n=63)] once daily for 25 days. Patients were not fluid-restricted and were maintained on stable doses of furosemide. At day 1, when compared with baseline, a decrease in body weight of −0.79±0.99, −0.96±0.93, and −0.84±0.02 kg was observed in the 30-, 45-, and 60-mg tolvaptan groups, respectively, and a body weight increase of +0.32±0.46 kg in the placebo group (P <0.001 for all treatment groups versus placebo). Although the initial decrease in body weight was maintained during the study, no further reduction was observed beyond the first day. An increase in urine volume was observed with tolvaptan when compared with placebo (3.9±0.6, 4.2±0.9, 4.6±0.4, and 2.3±0.2 L/24 hours at day 1 for 30-, 45-, and 60-mg tolvaptan groups, and placebo, respectively;P <0.001). A decrease in edema and a normalization of serum sodium in patients with hyponatremia were observed in the tolvaptan group but not in the placebo group. No significant changes in heart rate, blood pressure, serum potassium, or renal function were observed. Conclusions—In patients with CHF, tolvaptan was well tolerated; it reduced body weight and edema and normalized serum sodium in the hyponatremic patients.

Oral Tolvaptan Is Safe and Effective in Chronic Hyponatremia

Vasopressin antagonists increase the serum sodium concentration in patients who have euvolemia and hypervolemia with hyponatremia in the short term (</=30 days), but their safety and efficacy with longer term administration is unknown. SALTWATER was a multicenter, open-label extension of the Study of Ascending Levels of Tolvaptan in Hyponatremia (SALT-1 and SALT-2). In total, 111 patients with hyponatremia received oral tolvaptan for a mean follow-up of 701 days, providing 77,369 patient-days of exposure. All patients had hyponatremia at randomization in SALT-1 and SALT-2, and 85% continued to have hyponatremia at entry in SALTWATER. The most common adverse effects attributed to tolvaptan were pollakiuria, thirst, fatigue, dry mouth, polydipsia, and polyuria. Six drug-related adverse effects led to study discontinuation. The increase in serum sodium exceeded the desired 1 mmol/L per h at initiation in five patients. Hypernatremia (>145 mmol/L) led to discontinuation in one patient. Mean serum sodium increased from 130.8 mmol/L at baseline to >135 mmol/L throughout the observation period (P < 0.001 versus baseline at most points). Responses were comparable between patients with euvolemia and those with heart failure but more modest in patients with cirrhosis. In conclusion, prolonged administration of tolvaptan maintains an increased serum sodium with an acceptable margin of safety.

Acute Hemodynamic Effects of Tolvaptan, a Vasopressin V2 Receptor Blocker, in Patients With Symptomatic Heart Failure and Systolic Dysfunction : An International, Multicenter, Randomized, Placebo-Controlled Trial

OBJECTIVES This study sought to assess the acute hemodynamic effect of vasopressin V(2) receptor antagonism. BACKGROUND In decompensated heart failure (HF), tolvaptan, a vasopressin V(2) receptor antagonist, has been shown to improve congestion. It has not yet been established whether these improvements may be associated with the hemodynamic effects of tolvaptan. METHODS A total of 181 patients with advanced HF on standard therapy were randomized to double-blind treatment with tolvaptan at a single oral dose (15, 30, or 60 mg) or placebo. RESULTS Tolvaptan at all doses significantly reduced pulmonary capillary wedge pressure (-6.4 +/- 4.1 mm Hg, -5.7 +/- 4.6 mm Hg, -5.7 +/- 4.3 mm Hg, and -4.2 +/- 4.6 mm Hg for the 15-mg, 30-mg, 60-mg, and placebo groups, respectively; p < 0.05 for all tolvaptan vs. placebo). Tolvaptan also reduced right atrial pressure (-4.4 +/- 6.9 mm Hg [p < 0.05], -4.3 +/- 4.0 mm Hg [p < 0.05], -3.5 +/- 3.6 mm Hg, and -3.0 +/- 3.0 mm Hg for the 15-mg, 30-mg, 60-mg, and placebo groups, respectively) and pulmonary artery pressure (-5.6 +/- 4.2 mm Hg, -5.5 +/- 4.1 mm Hg, -5.2 +/- 6.1 mm Hg, and -3.0 +/- 4.7 mm Hg for the 15-mg, 30-mg, 60-mg, and placebo groups, respectively; p < 0.05). Tolvaptan increased urine output by 3 h in a dose-dependent manner (p < 0.0001), without changes in renal function. CONCLUSIONS In patients with advanced HF, tolvaptan resulted in favorable but modest changes in filling pressures associated with a significant increase in urine output. These data provide mechanistic support for the symptomatic improvements noted with tolvaptan in patients with decompensated HF. (Heart Pressure Assessment Study With Tolvaptan to Treat Congestive Heart Failure; NCT00132886).

Improvement in hyponatremia during hospitalization for worsening heart failure is associated with improved outcomes: insights from the Acute and Chronic Therapeutic Impact of a Vasopressin Antagonist in Chronic Heart Failure (ACTIV in CHF) trial

Background: Hyponatremia predicts poor outcome in patients with acute heart failure syndromes. This study evaluated the relationship between baseline serum sodium, change in serum sodium, and 60‐day mortality in hospitalized heart failure patients. Methods: A post‐hoc analysis of the ACTIV in CHF trial was performed. ACTIV in CHF randomized 319 patients hospitalized for worsening heart failure to placebo or one of three tolvaptan doses. Cox proportional hazards regression‐analysis was used to explore the relationship between baseline hyponatremia, sodium change during the hospitalization, and 60‐day mortality. Results: Hyponatremia was observed in 69 patients (21.6%). After covariate adjustment, baseline hyponatremia was a statistically significant predictor of 60‐day mortality (P = 0.0016). Follow‐up serum sodium data were available in 68 patients. At hospital discharge, 45 of 68 (66.2%) hyponatremic patients had improvements in serum sodium levels (⩾2 mmol/l). Hyponatremic patients with a serum sodium improvement had a mortality rate of 11.1% at 60 days post discharge, compared with a 21.7% mortality rate in those showing no improvement. After covariate adjustment, change in serum sodium was a statistically significant predictor of 60‐day mortality (HR: 0.736, 95% CI: 0.569–0.952 for each 1‐mmol/l increase in serum sodium from baseline). Conclusions: Serum sodium improvements during hospitalization for heart failure were associated with improved survival at 60 days.

Tolvaptan in Autosomal Dominant Polycystic Kidney Disease: Three Years' Experience

BACKGROUND AND OBJECTIVES Autosomal dominant polycystic kidney disease (ADPKD), a frequent cause of end-stage renal disease, has no cure. V2-specific vasopressin receptor antagonists delay disease progression in animal models. DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS This is a prospectively designed analysis of annual total kidney volume (TKV) and thrice annual estimated GFR (eGFR) measurements, from two 3-year studies of tolvaptan in 63 ADPKD subjects randomly matched 1:2 to historical controls by gender, hypertension, age, and baseline TKV or eGFR. Prespecified end points were group differences in log-TKV (primary) and eGFR (secondary) slopes for month 36 completers, using linear mixed model (LMM) analysis. Sensitivity analyses of primary and secondary end points included LMM using all subject data and mixed model repeated measures (MMRM) of change from baseline at each year. Pearson correlation tested the association between log-TKV and eGFR changes. RESULTS Fifty-one subjects (81%) completed 3 years of tolvaptan therapy; all experienced adverse events (AEs), with AEs accounting for six of 12 withdrawals. Baseline TKV (controls 1422, tolvaptan 1635 ml) and eGFR (both 62 ml/min per 1.73 m(2)) were similar. Control TKV increased 5.8% versus 1.7%/yr for tolvaptan (P < 0.001, estimated ratio of geometric mean 0.96 [95% confidence interval 0.95 to 0.97]). Corresponding annualized eGFR declined: -2.1 versus -0.71 ml/min per 1.73 m(2)/yr (P = 0.01, LMM group difference 1.1 ml/min per 1.73 m(2)/yr [95% confidence interval 0.24 to 1.9]). Sensitivity analyses including withdrawn subjects were similar, whereas MMRM analyses were significant at each year for TKV and nonsignificant for eGFR. Increasing TKV correlated with decreasing eGFR (r = -0.21, P < 0.01). CONCLUSION ADPKD cyst growth progresses more slowly with tolvaptan than in historical controls, but AEs are common.

Rationale and design of the TEMPO (Tolvaptan Efficacy and Safety in Management of Autosomal Dominant Polycystic Kidney Disease and its Outcomes) 3-4 Study.

BACKGROUND Current management of autosomal dominant polycystic kidney disease (ADPKD) is focused on treating disease complications, not on slowing cyst development or preventing progression to kidney failure. Tolvaptan, a selective vasopressin V2 (vasopressin 2) receptor antagonist, has been proved to inhibit kidney cyst growth and preserve kidney function in multiple animal models of polycystic kidney disease. The TEMPO (Tolvaptan Efficacy and Safety in Management of Autosomal Dominant Polycystic Kidney Disease and Its Outcomes) 3-4 Study will examine the long-term effectiveness and safety of tolvaptan in patients with ADPKD. We report baseline characteristics and revised power calculations for the trial. STUDY DESIGN A prospective, 3-year, multicenter, double-blind, placebo-controlled trial of tolvaptan, a selective V2 receptor antagonist. Primary outcome is total kidney volume percentage of change from baseline for tolvaptan relative to placebo. Secondary outcome parameters include time to ADPKD-associated complications (kidney function decrease, blood pressure control, renal pain, and albuminuria) and safety end points. SETTING & PARTICIPANTS This trial includes patients with ADPKD with relatively preserved kidney function (baseline estimated creatinine clearance ≥60 mL/min), aged 50 years or younger, and with total kidney volume measured using magnetic resonance imaging ≥750 mL. INTERVENTION Administration of placebo or tolvaptan, dose titrated to tolerance. OUTCOMES Number of subjects enrolled and baseline characteristics. MEASUREMENTS Total kidney volume, kidney function, albuminuria, kidney pain, and vital signs. RESULTS 1,445 patients with ADPKD were enrolled between March 2007 and January 2009. Preliminary baseline median total kidney volume was 1.46 L, and estimated creatinine clearance was 105 ± 34 mL/min. A prespecified blinded sample-size recalculation at two-thirds enrollment confirmed the likely power of the study to detect 20% differences from placebo in the primary and key secondary end points at P < 0.05. LIMITATIONS This is a preselected ADPKD population chosen for its risk of progression to kidney failure and may not represent the general ADPKD population. If study results are positive with regard to the primary end point, positive effects on other secondary clinical outcomes will be required to assess overall benefit. CONCLUSIONS This randomized trial is the largest clinical study of a proposed ADPKD intervention to date. It targets patients with ADPKD with early disease who are projected to have rapid cyst growth and accelerated outcomes. Blockade of vasopressin V2 receptor is hypothesized to inhibit cyst growth, thereby delaying additional adverse clinical outcomes.

Weight changes after hospitalization for worsening heart failure and subsequent re-hospitalization and mortality in the EVEREST trial

AIMS Increases in body weight (BW) are important determinants for hospitalization in ambulatory patients with heart failure (HF), but have not yet been explored in patients hospitalized for worsening HF. We explore the relationship between change in BW after hospitalization for worsening HF and risk for repeat hospitalization and mortality in the EVEREST trial. METHODS AND RESULTS The EVEREST trial randomized 4133 patients hospitalized for worsening HF and low ejection fraction (< or =40%) to tolvaptan, a vasopressin antagonist, or placebo. Following discharge, BW was assessed at 1, 4, and 8 weeks, and every 8 weeks thereafter. A time-dependent Cox proportional Hazard model explored the relationship between change in BW at 60, 120, and 180 days from discharge and the risks of HF hospitalization, cardiovascular (CV) hospitalization, and all-cause mortality. For subjects re-hospitalized for heart failure at 60, 120, and 180 days after discharge, mean BW increase prior to the event was 1.96, 2.07, and 1.97 kg, respectively, compared with 0.74, 0.90, and 1.04 kg in patients without re-hospitalization (P < 0.001 all groups). A similar pattern was observed with CV hospitalization. However, increases in BW were not predictive of all-cause mortality. CONCLUSION Increases in BW after hospitalization for worsening HF was predictive of repeat hospitalization events, but not mortality in the post-discharge period.

Efficacy and Safety of Brexpiprazole for the Treatment of Acute Schizophrenia: A 6-Week Randomized, Double-Blind, Placebo-Controlled Trial

OBJECTIVE The efficacy, safety, and tolerability of brexpiprazole and placebo were compared in adults with acute schizophrenia. METHOD This was a multicenter, randomized, double-blind, placebo-controlled study. Patients with schizophrenia experiencing an acute exacerbation were randomly assigned to daily brexpiprazole at a dosage of 0.25, 2, or 4 mg or placebo (1:2:2:2) for 6 weeks. Outcomes included change from baseline to week 6 in Positive and Negative Syndrome Scale (PANSS) total score (primary endpoint measure), Clinical Global Impressions Scale (CGI) severity score (key secondary endpoint measure), and other efficacy and tolerability measures. RESULTS The baseline overall mean PANSS total score was 95.2, and the CGI severity score was 4.9. Study completion rates were 62.2%, 68.1%, and 67.2% for patients in the 0.25-, 2-, and 4-mg brexpiprazole groups, respectively, versus 59.2% in the placebo group. At week 6, compared with placebo, brexpiprazole dosages of 2 and 4 mg produced statistically significantly greater reductions in PANSS total score (treatment differences: -8.72 and -7.64, respectively) and CGI severity score (treatment differences: -0.33 and -0.38). The most common treatment-emergent adverse event for brexpiprazole was akathisia (2 mg: 4.4%; 4 mg: 7.2%; placebo: 2.2%). Weight gain with brexpiprazole was moderate (1.45 and 1.28 kg for 2 and 4 mg, respectively, versus 0.42 kg for placebo at week 6). There were no clinically or statistically significant changes from baseline in lipid and glucose levels and extrapyramidal symptom ratings. CONCLUSIONS Brexpiprazole at dosages of 2 and 4 mg/day demonstrated statistically significant efficacy compared with placebo and good tolerability for patients with an acute schizophrenia exacerbation.

Effect of Tolvaptan in Autosomal Dominant Polycystic Kidney Disease by CKD Stage: Results from the TEMPO 3:4 Trial

BACKGROUND and objectives The Tolvaptan Efficacy and Safety in Management of Autosomal Dominant Polycystic Kidney Disease and Its Outcomes 3:4 study demonstrated a significant beneficial effect of the vasopressin V2 receptor antagonist tolvaptan on rates of kidney growth and eGFR decline in autosomal dominant polycystic kidney disease (ADPKD). This post hoc analysis was performed to reassess the primary and secondary efficacy endpoints by CKD stage at baseline. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS In a phase 3, multicenter, double-blind, placebo-controlled, 3-year trial, 1445 patients with ADPKD (age 18-50 years), with total kidney volume (TKV) ≥750 ml and estimated creatinine clearance ≥60 ml/min, were randomly assigned 2:1 to split-dose tolvaptan (45/15, 60/30, or 90/30 mg daily as tolerated) or placebo. The primary endpoint was annualized rate of TKV change. Secondary endpoints included a composite endpoint of time to multiple composite ADPKD-related events (worsening kidney function, kidney pain, hypertension, and albuminuria) and rate of kidney function decline. RESULTS Tolvaptan reduced annualized TKV growth by 1.99%, 3.12%, and 2.61% per year (all P<0.001; subgroup-treatment interaction, P=0.17) and eGFR decline by 0.40 in CKD1 (P=0.23), 1.13 in CKD2 (P<0.001) and 1.66 ml/min per 1.73 m(2) per year in CKD3 (P<0.001) with a trend for a positive subgroup-treatment interaction (P=0.07) across CKD1, CKD2 and CKD3. ADPKD-related events were less frequent in tolvaptan recipients than in placebo recipients among those with CKD1 (hazard ratio [HR], 0.83; 95% confidence interval [95% CI], 0.70-0.98; P=0.03) and those with CKD 3 (HR, 0.71; 95% CI, 0.57-0.89; P=0.003), but not among those with CKD2 (HR, 1.02; 95% CI, 0.85-1.21; P=0.86). Aquaresis-related adverse events (more frequent in the tolvaptan group) and ADPKD-related adverse events (more frequent in the placebo group) were not associated with CKD stage. Hypernatremia events in tolvaptan-treated patients with CKD3 and plasma aminotransferase elevations in tolvaptan-treated patients across CKD stages 1-3 occurred more frequently than in placebo recipients. CONCLUSIONS This post hoc analysis suggests clinically similar beneficial effects of tolvaptan in ADPKD across CKD stages 1-3.