Effects of tolvaptan in patients with chronic kidney disease and chronic heart failure

Thirst intensity survey in ADPKD patients

INTRODUCTION

With increased fluid intake and tolvaptan treatment, the growth rate of cysts can be theoretically decelerated in autosomal polycystic kidney disease. In this prospective study, it was planned to evaluate thirst sensation in these patients and the parameters affecting its intensity.

METHODS

Forty-one ADPKD patients on tolvaptan and 40 ADPKD patients not on tolvaptan as the control group were evaluated for thirst distress sensation and intensity. The feeling of thirst and the discomfort caused by excessive fluid intake was assessed with Thirst Distress Scale-HF 12 questions (60/12). Thirst intensity was evaluated with a 100 mm visual scale.

RESULTS

Of the whole group, 35.8% (29) were males, and 64.2% (52) were females. The mean age of the tolvaptan group was 39.17 ± 9.35 years and for the control group, it was 41.95 ± 12.29 years. There was a negative correlation between the thirst distress score of the patients and an increase in creatinine level after a year of tolvaptan treatment (r = - 0.335, p = 0.035). The patients not taking thiazide had higher thirst intensity scores (p = 0.004). There was no impact of tolvaptan dosage, total kidney volume, serum sodium, urinary osmolarity or eGFR on thirst distress and thirst intensity scores.

DISCUSSION/CONCLUSION

Only thiazide co-treatment had a positive impact on thirst distress and intensity when given tolvaptan. Thirst Distress Scale for ADPKD patients can be used to classify patients before and during tolvaptan treatment.

How should we treat acute kidney injury caused by renal congestion?

Decreased kidney function is associated with increased risk of cardiovascular events and mortality, and heart failure (HF) is a wellknown risk factor for renal dysfunction. Acute kidney injury (AKI) in patients with HF often is attributed to prerenal factors, such as renal hypoperfusion and ischemia as a result of decreased cardiac output. Another such factor is reduction of absolute or relative circulating blood volume, with the decrease in renal blood flow leading to renal hypoxia followed by a decrease in the glomerular filtration rate. However, renal congestion is increasingly being recognized as a potential cause of AKI in patients with HF. Increased central venous pressure and renal venous pressure lead to increased renal interstitial hydrostatic pressure and a reduction of the glomerular filtration rate. Both decreased kidney function and renal congestion have been shown to be important prognostic factors of HF, and adequate control of congestion is important for improving kidney function. Loop and thiazide diuretics are recommended as standard therapies to reduce volume overload. However, these agents are associated with worsening renal function even though they are effective for improving congestive symptoms. There is growing interest in tolvaptan, which can improve renal congestion by increasing excretion of free water and decreasing the required dose of loop diuretic, thereby improving kidney function. This review summarizes renal hemodynamics, the pathogenesis of AKI due to renal ischemia and renal congestion, and diagnosis and treatment options for renal congestion.

Impact of urine cyclic AMP relative to plasma arginine vasopressin on response to tolvaptan in patients with chronic kidney disease and heart failure

BACKGROUND

The clinical utility of tolvaptan in chronic kidney disease (CKD) patients with heart failure remains uncertain. The level of urine cyclic adenosine monophosphate (AMP) relative to plasma arginine vasopressin (AVP) indicates the residual function of the collecting ducts in response to AVP stimulation and might be a key to predicting response of tolvaptan.

METHODS

CKD patients who were hospitalized to treat their congestive heart failure refractory to conventional loop diuretics were considered to receive tolvaptan and included in this prospective study. The impact of urine cyclic AMP/plasma AVP ratio for prediction of response to tolvaptan, which was defined as any increase in urine volume at day 7 from day 0, was investigated.

RESULTS

A total of 30 patients (median 75 years old, 24 men, and median estimated glomerular filtration rate 14.4 mL/min/1.73 m²) were included. As compared to baseline, urine volume increased at day 7 in 17 responders, whereas urine volume decreased at day 7 in 13 non-responders. Baseline urine cyclic AMP/plasma AVP ratio distributed between 0.25 and 4.01 with median 1.90. The urine cyclic AMP/plasma AVP ratio was a significant predictor of response to tolvaptan, which was adjusted for 6 potential confounders with a cutoff of 1.24.

CONCLUSIONS

Baseline urine cyclic AMP/plasma AVP ratio is an independent predictor of response to tolvaptan in advanced CKD patients with heart failure.

CLINICAL TRIAL REGISTRATION

UMIN000022422.

Effect of Tolvaptan in Patients with Chronic Kidney Disease Stage G5, and Impact of Concomitant Use of Thiazide Diuretics: A Retrospective Cohort Study

BACKGROUND

The diuretic effect of tolvaptan, a vasopressin V2 receptor antagonist, in patients with severe renal dysfunction remains poorly characterized. Thiazide diuretics reduce urinary volume (UV) in patients with nephrogenic diabetes insipidus, which lacks V2 receptor function.

OBJECTIVE

This retrospective study investigated the acute urinary effects of tolvaptan in patients with stage G5 chronic kidney disease and congestive heart failure (CHF), and the impact of thiazide diuretics on the urinary effects of tolvaptan.

METHODS

UVs 24 h before and after tolvaptan administration and 30-day dialysis initiation rate were compared between patients with and without thiazide diuretic administration.

RESULTS

Thiazide diuretics were used in 26 of the 106 recruited patients (age 73.4 ± 13.0 years; estimated glomerular filtration rate 8.07 ± 3.13 mL/min/1.73 m²). The pre- and post-tolvaptan 24-h UVs were significantly higher in patients not administered thiazide diuretics (1043.4 ± 645.6 vs. 1422.2 ± 774.0 mL/day; p < 0.001) than in those administered thiazide diuretics (1177.3 ± 686.5 vs. 1173.1 ± 629.1 mL/day; p = 0.93). In a multivariate regression model, thiazide diuretic use was significantly associated with decreased 24-h UV (β coefficient - 486.7, 95% confidence interval [CI] - 674.5 to - 298.8); increased urine osmolality (β coefficient 37.7, 95% CI 17.1-58.4); increased body weight (β coefficient 0.62, 95% CI 0.31-0.92); and increased 30-day dialysis initiation rate (odds ratio 3.40, 95% CI 1.18-9.82) after tolvaptan administration.

CONCLUSIONS

Tolvaptan exhibited significant diuretic effects in patients with CHF, including those with severe renal dysfunction, which were diminished with concomitant thiazide diuretic use.

Efficacy and Safety of Combination Therapy with Tolvaptan and Furosemide in Children with Nephrotic Syndrome and Refractory Edema: A Prospective Interventional Study

OBJECTIVE

Severe edema in children with nephrotic syndrome is often refractory to conventional diuretics. Tolvaptan has been used satisfactorily for managing edema in patients with heart failure and cirrhosis. The safety and efficacy of combination therapy with oral tolvaptan and intravenous (IV) furosemide was assessed in patients with furosemide refractory edema.

METHODS

Patients, aged 5-18 y with nephrotic syndrome and severe edema, were screened for eligibility. After excluding hypovolemia, patients received IV furosemide (3-4 mg/kg/d) for 48 h. Those refractory to IV furosemide (weight loss < 3%) received tolvaptan (0.5-1 mg/kg once daily) and IV furosemide for the next 48 h. Parameters were compared between 48 h of furosemide alone and combination therapy.

RESULTS

A total of 24 patients (18 boys) with mean age of 8.0 ± 3.0 y were enrolled. Urine volume significantly increased with combination therapy as compared to furosemide therapy (mean difference: 1.2 mL/kg/h; 95% CI: 0.8-1.65 mL/kg/h) (p < 0.001). Compared to therapy with furosemide alone, combination therapy resulted in significant reduction in body weight from 26.9 ± 10.3 kg to 24.8 ± 9.7 kg (p < 0.001). Estimated glomerular filtration rate did not change (p = 0.81) but serum sodium increased from 135.7 ± 3.3 mEq/L to 140.4 ± 4.8 mEq/L (p < 0.001) with combination therapy; 2 patients showed asymptomatic hypernatremia.

CONCLUSION

The combination of oral tolvaptan and IV furosemide is effective in augmenting diuresis and reducing weight in patients with furosemide refractory edema but requires monitoring of electrolytes and volume status.

Efficacy of tolvaptan on advanced chronic kidney disease with heart failure: a randomized controlled trial

Background

Tolvaptan (TLV) is reported to improve diuretic effects in patients with chronic kidney disease (CKD) when furosemide (FUR) is not sufficiently effective. However, it is not clear whether TLV addition is effective for advanced CKD patients with heart failure.

Methods

An open-label, parallel-group randomized trial was performed. The subjects were 33 patients with CKD stage G3–G5 who had fluid overload despite taking 20–100 mg/day FUR. They were divided into two groups: a group administered 15 mg/day TLV plus their original FUR dose for 7 days (TLV group), and a group administered 120–200 mg/day FUR (i.e., 100 mg/day over their previous dose) for 7 days (FUR group).

Results

The mean change in urine volume was significantly higher in the TLV group compared to the FUR group (637 ml vs 119 ml; p < 0.05). The difference was greater when the urine osmolality before treatment was high. Serum creatinine was increased only in the FUR group. The incidence of worsening renal function (WRF) was significantly lower in the TLV group (18.8% vs 58.8%; p < 0.05). Serum sodium decreased significantly in the FUR group, but did not change in the TLV group.

Conclusions

In patients with advanced CKD with fluid overload, the addition of TLV achieved a significantly higher urine volume with less adverse effects on renal function compared with increasing the dose of FUR. The efficacy and safety of TLV were higher in patients who had higher urine osmolality and lower serum sodium before treatment.

Clinical trial registration

UMIN000014763.

Long-term Benefits of Treatment with Tolvaptan in Patients with Autosomal Dominant Polycystic Kidney Disease

BACKGROUND

Tolvaptan is the first effective drug treatment for autosomal dominant polycystic kidney disease (ADPKD) patients, but few long-term observations of the effects of tolvaptan have been reported.

METHODS

In this single center, retrospective cohort study, we investigated nine patients who participated in a phase 3 trial of tolvaptan for ADPKD patients at our hospital between 2008 and 2014. Six of the patients discontinued tolvaptan at the end of the clinical trial and were defined as the discontinuation group, and three continued to take it; these were defined as the continuation group. The observation period was 3 years before and after the end of the tolvaptan trial, and we compared the following data in each group: serum creatinine, estimated glomerular filtration rate (eGFR), total kidney volume, serum sodium concentration, and urine specific gravity.

RESULTS

eGFR was significantly improved after the end of the trial in the continuation group (P = 0.0446), but there was no significant change in the regression line before and after the end of the trial in the discontinuation group. The increases in mean total kidney volume rates over the 3 years before and after the trial were 0.01 %/year vs. 0.067 %/year in the discontinuation group (P = 0.0247). On the other hand, serum sodium concentration and urine specific gravity showed no change during the observation period.

CONCLUSION

This study suggested that long-term administration of tolvaptan may improve renal function and inhibit total kidney volume growth.

Efficacy and safety of oral tolvaptan in patients undergoing hemodialysis: a Phase 2, double-blind, randomized, placebo-controlled trial

BACKGROUND

Loop diuretics are used to manage fluid retention in patients with end-stage kidney disease undergoing hemodialysis (HD). This randomized, double-blind, placebo-controlled, Phase 2 trial evaluated the efficacy and safety of tolvaptan, a vasopressin V2 receptor antagonist, in Japanese HD patients.

METHODS

A total of 124 patients (24-h urine volume ≥500 mL) on thrice-weekly HD were randomized to receive oral tolvaptan 15 mg/day (n = 40), tolvaptan 30 mg/day (n = 40) or placebo (n = 44) for 24 weeks. Efficacy endpoints were change from baseline in 24-h urine volume, total fluid removal by HD per week and interdialytic weight gain (IDWG). Safety was assessed via the incidence of treatment-emergent adverse events (TEAEs).

RESULTS

At treatment end, the difference (95% confidence interval) from the placebo group in the mean change from baseline in 24-h urine volume was significant in the tolvaptan 15 mg {429.1 mL [95% confidence interval (CI) 231.0, 627.2]; P < 0.0001} and 30 mg [371.6 mL (95% CI 144.1, 599.2); P = 0.0017] groups. The mean changes from baseline in total fluid removal by HD and IDWG were not significantly different in the tolvaptan groups versus the placebo group. Although the proportion of patients with TEAEs was lower in the placebo group (77.3%) than in the tolvaptan groups (92.3%), tolvaptan was safe and well-tolerated during the study period.

CONCLUSIONS

Tolvaptan significantly sustained diuretic action for 24 weeks in HD patients but did not reduce total fluid removal by HD per week and IDWG to the same extent.

Reversible splenial lesion syndrome (RESLES) due to acute intermittent porphyria with a novel mutation in the hydroxymethylbilane synthase gene

Background

Reversible splenial lesion syndrome (RESLES) is a clinico-radiological syndrome characterized by the presence of reversible lesions specifically involving the splenium of the corpus callosum (SCC). The cause of RESLES is unknown. However, infectious-related mild encephalitis/encephalopathy (MERS) with a reversible splenial lesion remains the most common cause of reversible splenial lesions. Acute intermittent porphyria (AIP) is an autosomal dominant disorder caused by a partial deficiency of porphobilinogen deaminase (PBGD), the third enzyme in the heme biosynthetic pathway. It can affect the autonomic, peripheral, and central nervous system.

Result

In this study, we report a 20-year-old woman with AIP who presented with MRI manifestations suggestive of RESLES, she had a novel HMBS nonsense mutation, a G to A mutation in base 594, which changed tryptophan to a stop codon (W198*). Conclusion: To the best of our knowledge, this is only one published case of RELES associated with AIP.

Impact of serum albumin levels on the body fluid response to tolvaptan in chronic kidney disease patients

PURPOSE

Tolvaptan exerts an aquaretic effect by blocking vasopressin V2 receptor. Although tolvaptan ameliorates body fluid retention even in patients with chronic kidney disease (CKD), predictors of body fluid reduction induced by tolvaptan remain unclear. We, therefore, examined the clinical parameters associated with the effect of tolvaptan on fluid volume in CKD patients.

METHODS

Twelve CKD patients (stage 3-5) with fluid retention were treated with tolvaptan in addition to conventional diuretic treatment. Patients were divided into low and high responders by the median change in total body water (TBW) for 1 week measured by a bioimpedance analysis (BIA) device, and clinical parameters were compared between the groups.

RESULTS

The body weight significantly decreased by 2.0 ± 2.3 kg (p = 0.005), but the estimated glomerular filtration rate (eGFR) was not significantly changed (16.9 ± 11.9 vs. 17.4 ± 12.4 mL/min/1.73 m², p = 0.139) after 1 week. The BIA showed that the intracellular water (ICW) decreased by 6.0% ± 4.7% (p < 0.001), the extracellular water (ECW) decreased by 6.7% ± 5.4% (p = 0.001), and the TBW decreased by 6.3% ± 4.9% (median value - 6.02%, p < 0.001). The serum albumin level in the high responders was significantly lower than in the low responders (2.3 ± 0.5 vs. 3.3 ± 0.8 g/dL, p = 0.013). Significant partial correlations adjusted for the eGFR were observed between the baseline serum albumin level and changes in the ICW (r = 0.440, p = 0.048), ECW (r = 0.593, p = 0.009) and TBW (r = 0.520, p = 0.020).

CONCLUSIONS

Serum albumin levels predict the body fluid response to tolvaptan in CKD patients. Tolvaptan may be a promising therapeutic option for ameliorating body fluid retention, especially in patients with hypoalbuminemia.

Different Effects on Fluid Distribution between Tolvaptan and Furosemide in a Liver Cirrhosis Patient with Chronic Kidney Disease

A 73-year-old man with liver cirrhosis and advanced chronic kidney disease was admitted to our hospital due to bilateral lower leg edema and appetite loss. Furosemide to treat fluid retention markedly decreased extracellular water compared with intracellular water, but the addition of tolvaptan equally decreased both with a greater diuretic response than furosemide alone. Furthermore, tolvaptan administration increased the plasma colloid osmotic pressure, which might facilitate the shift of fluid from the extravascular space to the intravascular space. This is the first case showing different effects on the fluid distribution between furosemide and additional tolvaptan in the same patient.

Efficacy of tolvaptan for chronic heart failure: Study protocol for a systematic review of randomized controlled trial

BACKGROUND

The protocol of this study will be proposed for systematic evaluation of the efficacy and safety of tolvaptan in the treatment of chronic heart failure (CHF).

METHODS

We will retrieve the following electronic databases for randomized controlled trials assessing the efficacy of tolvaptan in patients with CHF: PubMed, Embase, Cochrane Central Register of Controlled Trials, Web of Science, Scopus, Chinese Biomedical Literature Database, China National Knowledge Infrastructure, VIP Information, and Wanfang Data. Each database will be retrieved from inception to February 1, 2019 without any limitations. The entire process of study selection, data extraction, and methodological quality evaluation will be conducted by 2 independent authors.

RESULTS

The protocol of this proposed study will compare the efficacy and safety of tolvaptan in the treatment of patients with CHF. The outcomes will include all-cause mortality, change in body weight, urine output, change in serum sodium; and incidence of all adverse events.

CONCLUSION

The findings of this proposed study will summarize the current evidence of tolvaptan for CHF.

ETHICS AND DISSEMINATION

All data used in this systematic review will be collected from the previous published trials. Thus, no research ethics approval is needed for this study. The findings of this study will be published at a peer-reviewed journal.

PROSPERO REGISTRATION NUMBER

PROSPERO CRD42019120818.

Effects of tolvaptan on renal function in chronic kidney disease patients with volume overload

Background

Fluid overload in chronic kidney disease (CKD) is generally controlled by diuretics, with potentially harmful effects on renal function. The efficacy of tolvaptan, a vasopressin V2-receptor antagonist and aquaretic, has not been evaluated for fluid control in CKD with reduced renal function.

Methods

Each patient from a group of 24 CKD patients on tolvaptan 15 mg/d plus conventional diuretics (T group) was matched by age and sex with a patient from a group of 24 CKD patients on conventional nonaquaretic diuretics alone not associated to tolvaptan other than tolvaptan (C group). Changes in renal function were compared between the groups for 1 year.

Results

There were no significant differences in blood pressure, hemoglobin levels, cardiac function, urine specific gravity, and urinary sodium concentration between the 2 groups at the beginning of the follow-up period and 1 year after. The estimated glomerular filtration rate (eGFR) by the formula developed by Japanese Society of Nephrology (in mL/min/1.73 m²) decreased: C group (from 28.3±13.6 to 23.0±12.3, p=0.09), T group (from 22.7±12.4 to 19.4±12.2, p=0.18), but both did not reach significance. A 50% reduction in eGFR was observed in 4 patients in the C group and 1 in the T group (p<0.05). A subgroup analysis performed on the patients with stage 3-4 CKD demonstrated a significant reduction in eGFR in the C group (n=17, p=0.04), but not in T group (n=17, p=0.07).

Conclusion

These results suggest that tolvaptan may have less effects on CKD progression among stage 3-4 CKD patients who are on conventional diuretics.