Oral lyophylizate formulation of desmopressin: superior pharmacodynamics compared to tablet due to low food interaction

Potential clinical applications of current and future oral forms of desmopressin (Review)

Desmopressin is a synthetic analogue of vasopressin and a selective vasopressin receptor 2 agonist. It was first synthesised in 1967 and utilised for its antidiuretic properties. It is also used in bleeding disorders to enhance clotting. Other potential uses of the drug have been reported. The present review aims to provide a broad overview of the literature on potential further uses of oral forms of desmopressin. Key therapeutic areas of interest were identified based on known physiological activities/targets of desmopressin or reports of an effect of desmopressin in the literature. The feasibility of adequate dosing with oral forms of the drug was also considered. Systematic literature searches were carried out using the silvi.ai software for the identified areas, and summaries of available papers were included in tables and discussed. The results of the searches showed that desmopressin has been investigated for its efficacy in a number of areas, including bleeding control, renal colic, the central nervous system and oncology. Evidence suggests that oral desmopressin may have the potential to be of clinical benefit for renal colic and bleeding control in particular. However, further research is needed to clarify its effect in these areas, including randomised controlled studies and studies specifically of oral formulations (and doses). Further research may also yield findings for cancer, cognition and overactive bladder.

Desmopressin Dose Requirements in Adults with Congenital and Acquired Central Diabetes Insipidus

Central diabetes insipidus is a rare disorder characterized by a deficiency of vasopressin. The first line drug to treat this disorder is a synthetic analogue of vasopressin, desmopressin.The primary aim of this retrospective register study was to compare desmopressin dose requirements in patients with acquired and congenital DI, and secondly to assess the influence of BMI on dose requirement and risk of hyponatremia with different drug administrations. We included all patients with suspected DI attending the endocrine department at Rigshospitalet, Copenhagen, Denmark in 2022. We identified 222 patients who were included whereof 130/222 (58.6%) were females and median age was 53 years (IQR 35 to 63). The etiology included 7/222 (3.2%) congenital and 215/222 (96.8%) acquired. After converting nasal and sublingual doses to equivalent oral doses, the median daily dose requirement was 600 μg in patients with congenital etiology compared to 200 μg in patients with acquired etiology (p=0.005). We found no association between BMI and desmopressin dose requirements (p=0.6). During the past 12 months, 66/215 (30.7%) had sodium levels<136 mmol/l including 20/215 (9.3%) with sodium levels<131 mmol/l. No increased risk of hyponatremia was found, when nasal and oral were compared (p=0.9). Daily desmopressin dose requirements were higher in patients with congenital DI compared to patients with acquired DI. However, this result was associated with uncertainty due to the small congenital group. BMI did not influence daily dose requirements and nor did type of administration influence the risk of hyponatremia.

Effect of laser acupuncture on monosymptomatic nocturnal enuresis in adolescent females: A randomized controlled trial

BACKGROUND AND AIM

Nocturnal enuresis (NE) is prevalent in children and adolescents and affects their social life later. Therefore, the objective of this study was to ascertain laser acupuncture (LA) therapy's effect on NE in adolescent females.

METHODS

Sixty adolescent females diagnosed with chronic monosymptomatic nocturnal enuresis (MNE) were randomly divided into two equal groups: The intervention group (received LA and desmopressin) and the control group (received desmopressin only) (n = 30 each). Treatment was delivered and LA was used three times a week for 12 successive weeks. Abdominal ultrasonography and voiding calendar were used to assess bladder capacity and maximum voiding volume (MVV), respectively. The frequency of bed wetness was assessed throughout the trial period in a diary.

RESULTS

Statistically significant differences were reported in the intervention group. Bladder capacity significantly increased in the intervention group (LA and desmopressin) than in the control group.

CONCLUSIONS

The results of this study suggest the beneficial influences of LA on MNE, despite the very poor quality of the literature's available evidence.

The therapeutic effect of oral desmopressin lyophilisate formulation in children with central diabetes insipidus

OBJECTIVES

We aimed to assess the efficacy of oral use of oral desamino-D-arginine-8-vasopressin lyophilisate (OLD) in children with central diabetes insipidus (CDI).

METHODS

Clinical, laboratory, and imaging characteristics of twenty-five children with CDI treated with OLD were evaluated.

RESULTS

Fourteen boys and eleven girls with a mean age of 52.37 months were evaluated. These children (mean weight and height at admission, 26.81 ± 14.8 kg vs. 92.52 ± 30 cm) presented with failure to thrive, irritability, prolonged fever, polyuria and hypernatremia (mean sodium level, 143.12 ± 8.6 mEq/L). At the time of hypernatremia, mean serum and urine osmolality were 298.2 ± 18 mOsm/kg and 160.20 ± 8.7 mOsm/kg, respectively. ADH levels were undetectable (<0.5 pmol/L) at admission in all cases. Oral administration of desmopressin lyophilisate (120 µg/tablet) was initiated at a dose of 5 μg/kg/day in two divided doses together with controlled water intake to avoid hyponatremia. Serum sodium levels normalised in a mean duration of 15.2 ± 16.4 h with a mean decline rate of 0.12 ± 0.04 mEq/L/h. Nine children needed rehospitalization because of hypernatremia due to non-compliance. Four episode of hyponatremia was observed. Weight gain and growth were normal during the mean follow-up duration of 37.79 ± 48.2 months.

CONCLUSIONS

Administration of OLD was practical and safe in the treatment of CDI in children with CNS malformations in this small retrospective series.

Management of Central Diabetes Insipidus in Disabled Children with Diluted Oral Desmopressin Lyophilisate Formulation Administered Through Nasogastric Tube: A Retrospective Case Series

BACKGROUND

Experience with nasogastric administration of oral DDAVP [desamino-D-arginine-8-vasopressin] lyophilisate (ODL) for central diabetes insipidus (CDI) in disabled children with swallowing coordination difficulties is limited.

OBJECTIVE

We aimed to assess the safety and efficacy of nasogastric use of ODL in disabled children with CDI. Time to serum sodium normalisation was compared with that of children with normal intellect and CDI treated with sublingual DDAVP.

METHODS

Clinical, laboratory and neuroimaging characteristics were evaluated for 12 disabled children with CDI treated with ODL through nasogastric tube at Dr Behcet Uz Children's Hospital, Turkey, between 2012 and 2022.

RESULTS

Six boys and six girls with a mean (±SD) age of 43 (± 40) months were evaluated. These children (mean [±SD] weight standard deviation score [SDS] - 1.2 ± 1.7; mean [±SD] height SDS - 1.3 ± 1.4) presented with failure to thrive, irritability, prolonged fever, polyuria and hypernatraemia (mean serum sodium 162 [±3.6] mEq/L). At diagnosis, mean serum and urine osmolality were 321 (± 14) mOsm/kg and 105 (± 7.8) mOsm/kg, respectively. Arginine vasopressin (AVP) levels were undetectable (< 0.5 pmol/L) at diagnosis in all patients. Nasogastric tube administration of DDAVP lyophilisate (120 µg/tablet) dissolved in water (10 mL) was commenced at a dose of 1-5 µg/kg/day in two divided doses together with controlled water intake to avoid hyponatraemia. The frequency and dose of DDAVP were titrated based on urine output and serum sodium concentration. Serum sodium declined at a rate of 0.11 ± 0.03 mEq/L/h and reached normal range in a mean duration of 174 ± 46.5 h. Serum sodium declined faster in children with normal intellect and CDI treated with sublingual DDAVP (1.28 ± 0.39 mEq/L/h; p = 0.0003). Three disabled children needed rehospitalisation because of hypernatraemia due to unintentional DDAVP omission by caregivers. No episode of hyponatraemia was observed. Weight gain and growth were normal during the median (± interquartile range) follow-up duration of 32 ± 67 months.

CONCLUSIONS

Nasogastric administration of oral DDAVP lyophilised formulation was safe and effective in the treatment of CDI in disabled children in this small retrospective series.

Fundamental advances in hydrogels for the development of the next generation of smart delivery systems as biopharmaceuticals

Recent advances in developing and applying therapeutic peptides for anticancer, antimicrobial and immunomodulatory remedies have opened a new era in therapeutics. This development has resulted in the engineering of new biologics as part of a concerted effort by the pharmaceutical industry. Many alternative routes of administration and delivery vehicles, targeting better patient compliance and optimal therapeutic bioavailability, have emerged. However, the design of drug delivery systems to protect a range of unstable macromolecules, including peptides and proteins, from high temperatures, acidic environments, and enzymatic degradation remains a priority. Herein, we give chronological insights in the development of controlled-release drug delivery systems that occurred in the last 70 years or so. Subsequently, we summarise the key physicochemical characteristics of hydrogels contributing to the development of protective delivery systems concerning drug-targeted delivery in the chronospatial domain for biopharmaceuticals. Furthermore, we shed some light on promising hydrogels that can be utilised for systemic bioactive administration.

Primary enuresis in adults: pathogenesis, clinical course and modern approaches to treatment: A review

The review article presents current data on the epidemiology, classification, pathogenesis, risk factors, diagnosis, and features of the clinical course of primary enuresis in adults. The main methods of treatment of patients with primary enuresis are described in detail. It has been shown that in the treatment of this category of patients, the leading role is given to the use of a synthetic analogue of the antidiuretic hormone desmopressin. A detailed analysis of the pharmacological properties and clinical use of desmopressin in patients with primary enuresis is presented. The advantages of prescribing a sublingual form of desmopressin, which ensures its high efficiency and good tolerability of therapy.

Better outcomes with desmopressin melt than enuretic alarm therapy in children with nocturnal enuresis during coronavirus disease 2019 (COVID-19)

Objectives

This study aimed to investigate the effect of the coronavirus disease 2019 (COVID-19) pandemic on the treatment of children with primary monosymptomatic nocturnal enuresis (MNE) with desmopressin melt versus an enuresis alarm.

Materials and methods

This study included 56 children with primary MNE who were taking desmopressin melt or using an alarm. Their anxiety levels were evaluated using the Social Anxiety Scale for Children-Revised. For both treatment methods, data from a 3-month bedwetting diary between the third and sixth months of the pre-pandemic treatment were compared with those assessed during the same period during the pandemic.

Results

Prior to the COVID-19 pandemic, the median 3-month mean frequency of MNE was 1 (0-7.67) in children using desmopressin melt versus 1.33 (0-6) in those using alarm treatment (p = 0.095). During the COVID-19 pandemic period, the median monthly mean frequency of MNE was 1.33 (0-7.33) in children using desmopressin melt versus 6 (1.33-13) in those using alarm treatment (p < 0.001).

Conclusions

The COVID-19 pandemic and its accompanying psychological effects did not affect the treatment efficacy of desmopressin melt in children with primary MNE but did adversely affect that of enuresis alarms.

Desmopressin therapy in children and adults: pharmacological considerations and clinical implications

PURPOSE

This review aims to provide prescribing clinicians a deeper appreciation of desmopressin's clinical indications and formulation types, to better balance efficacy and safety through proper formulation selection.

BACKGROUND

Since its discovery 50 years ago, desmopressin's antidiuretic properties have been used for central diabetes insipidus, primary monosymptomatic nocturnal enuresis and adult nocturnal polyuria, while its coagulant effects are useful for mild hemophilia A and von Willebrand Disease. During this time, newer formulations of desmopressin have also been introduced to the market raising questions on interchangeability, dose conversion and safety. The wide array of clinical indications and variable pharmacokinetic properties of different desmopressin preparations raises the possibility of medication error, especially the risk of hyponatraemia.

METHODOLOGY

A narrative review to explore clinically relevant aspects of desmopressin therapy, synthesising information obtained from searches of published literature.

RESULTS

We identified that the risk factors for developing hyponatremia include extremes of age, existing comorbidity, drug interaction, intranasal formulations and intercurrent illness. We describe the dose equivalence between all formulations to facilitate conversion. We highlight that in view of inter-subject variability, close monitoring is recommended when switching preparations. We found that paediatric data remains limited, leading to recent proposals for age- and weight-based dosing regimens.

CONCLUSION

The risk of hyponatremia, albeit small, can be reduced by adhering to the indication-specific doses and taking steps to govern the safe prescription of the drug. Further paediatric clinical trials are awaited to expand the evidence base of childhood desmopressin therapy.

Desmopressin acetate the first sublingual tablet to treat nocturia due to nocturnal polyuria

Introduction: Desmopressin was widely used to treat nocturnal polyuria in adults under the age of 65 due to the well-established risk of hyponatremia. Since the prevalence of nocturia increases with age, and with an aging population, those most affected were excluded from treatment. Recently, a new lower dose sublingual tablet formulation that optimizes the balance between efficacy and tolerability has been licensed for symptomatic treatment of nocturia due to idiopathic nocturnal polyuria in adults of any age, with the caveat of regular serum monitoring for those over 65. This newer formulation aims to achieve the same clinical outcomes as previous formulations while reducing the risk of hyponatremia.Areas covered: This review will look at the pharmacology of the newly formulated desmopressin and examine the results of the clinical trials that would support its treatment of adult nocturia with idiopathic nocturnal polyuria.Expert opinion: When reporting on the clinical efficacy of desmopressin on nocturia, it is important for clinical trials to publish their complete data on nocturnal and 24-hour urine voided volumes. Further research examining the physiological reasoning behind this gender-specific dosing for desmopressin and the optimal recommended treatment duration of desmopressin for those over 65 is needed.

Development and evaluation of a composite dosage form containing desmopressin acetate for buccal administration

Desmopressin acetate (DDAVP) is an oligopeptide indicated for the treatment of primary nocturnal enuresis, for example. The poor oral bioavailability of DDAVP accelerated a shift to alternative routes of administration like nasal and oromucosal, whereby nasal administration results in high fluctuations increasing the risk of undesirable side effects. Aim of the study was to use a new composite dosage form (solid matrix attached to a bilayer mucoadhesive film) to make DDAVP available via oromucosal route, reducing the risk of undesirable side effects through precise dosing. DDAVP was incorporated into a solid matrix in the form of a minitablet, and both direct tableting (AV > 30) and granulation followed by tableting (AV = 17.86) were compared. Minitablets with content uniformity could only be obtained by granulation and loss supplementation (AV = 11.27) with immediate drug release (>80% after 7–8 min) and rapid disintegration (<49 s). Permeation studies were performed with a clinically relevant dose (200 μg) in a time interval of up to one hour, resulting in apparent permeation coefficients of 4.90 × 10⁻⁶ cm/s (minitablet) and 2.04 × 10⁻⁶ cm/s (composite). Comparable fluctuations showed no inferiority of composite and minitablet regarding dosing accuracy. Thus, a step towards controlled and dose-accurate transmucosal delivery of systemically active DDAVP could be achieved.

Desmopressin oral lyophilisate in young children: new insights in pharmacokinetics and pharmacodynamics

OBJECTIVE

To study the pharmacokinetic (PK)/pharmacodynamic (PD) characteristics of desmopressin (dDAVP) oral lyophilisate in children below the age of 8 years with special emphasis on age-related and size-related differences in bioavailability.

DESIGN

Open label, non-randomised, interventional PK and PD trial.

SETTING

Single-centre study.

PATIENTS

Children (age: 6 months to 8 years) with nocturnal polyuria, including both children with uropathy or nephropathy (glomerular filtration rate >60 mL/min/1.73 m²) and children (age: 5-8 years) with severe monosymptomatic nocturnal enuresis, who were unresponsive to treatment with 400 µg of the dDAVP tablet for at least 1 month.

INTERVENTIONS

After a water load, dDAVP was administered sublingually as a single dose of oral lyophilisate. Subsequently, blood and urine samples were collected until 7 hours post-administration.

MAIN OUTCOME MEASURES

Non-compartmental analysis of PK parameters was performed based on dDAVP concentrations in both plasma and urine. To evaluate the effect of dDAVP lyophilisate (PD parameters), the urinary concentration capacity (urine osmolality (mOsm/kg)) and antidiuretic effect (diuresis rate (mL/kg/h)) were calculated.

RESULTS

The PK data support the need for size-dependent dosing in children. Body weight was shown to be a significant covariate for apparent clearance (CL/F) and apparent volume of distribution (V_d/F). A double absorption peak of dDAVP lyophilisate in the first 2 hours post-administration was demonstrated.

CONCLUSIONS

For the first time, a double absorption profile of dDAVP lyophilisate was found in children, questioning extrapolation of bioequivalence from adults towards children. Moreover, the need for size-adapted dosing regimens of dDAVP lyophilisate in young children is indicated.

TRIAL REGISTRATION NUMBER

NTC02584231.

An Integrated Paediatric Population PK/PD Analysis of dDAVP: How do PK Differences Translate to Clinical Outcomes?

INTRODUCTION

The bioequivalence of two formulations of desmopressin (dDAVP), a vasopressin analogue prescribed for nocturnal enuresis treatment in children, has been previously confirmed in adults but not in children. In this study, we aimed to study the pharmacokinetics (PK) and pharmacodynamics (PD) of these two formulations, in both fasted and fed children, including patients younger than 6 years of age.

METHODS

Previously published data from one PK study and one PK/PD study in children aged between 6 and 16 years were combined with a new PK/PD study in children aged between 6 months and 8 years, and analysed using population PK/PD modelling. Simulations were performed to further explore the relative bioavailability of both formulations and evaluate current dosing strategies.

RESULTS

The complex absorption behaviour of the lyophilizate was modelled using a double input, linked to a one-compartmental model with linear elimination and an indirect response model linking dDAVP concentration to produced urine volume and osmolality. The final model described the observed data well and elucidated the complexity of bioequivalence and therapeutic equivalence of the two formulations. Simulations showed that current dosing regimens using a fixed dose of lyophilizate 120 μg is not adequate for children, assuming children to be in the fed state when taking dDAVP. A new age- and weight-based dosing regimen was suggested and was shown to lead to improved, better tailored effects.

CONCLUSIONS

Bioequivalence and therapeutic equivalence data of two formulations of the same drug in adults cannot be readily extrapolated to children. This study shows the importance of well-designed paediatric clinical trials and how they can be analysed using mixed-effects modelling to make clinically relevant inferences. A follow-up clinical trial testing the proposed dDAVP dosing regimen should be performed.

CLINICAL TRIAL REGISTRATION

This trial has been registered at www.clinicaltrials.gov (identifier NCT02584231; EudraCT 2014-005200-13).

Nocturnal enuresis in children: The role of arginine-vasopressin

Nocturnal enuresis is the involuntary pass of urine during sleep beyond the age of 5 years. It is a common condition in childhood and has an impact on the child's well-being. Research into the pathophysiology of the condition in the last decades has led to a paradigm shift, and enuresis is no longer considered a psychiatric disorder but rather a maturation defect with a somatic background. An excess urine production during sleep is a common finding in children with enuresis and disturbances in the circadian rhythm of arginine-vasopressin (AVP) is found in the majority of children with nocturnal polyuria. Children with enuresis and nocturnal polyuria lack the physiologic increase in AVP levels during sleep and treatment with the AVP analogue desmopressin can restore this rhythm and lead to dry nights. The reasons for this aberrant circadian AVP rhythm are not established. Furthermore, not all children with enuresis and nocturnal polyuria can be successfully treated with desmopressin suggesting that factors beyond renal water handling can be implicated such as natriuresis, hypercalciuria, and sleep-disordered breathing. The advances in the research of the genetic background of the condition may shed further light on the enuresis pathophysiology.

Comparison of the efficacy of desmopressin fast-melting formulation and enuretic alarm in the treatment of monosymptomatic nocturnal enuresis

BACKGROUND

Primary monosymptomatic nocturnal enuresis (MNE) is a common pediatric condition and there are two firstline, evidence-based treatments available; desmopressin and the enuresis alarm. Although there are many studies comparing enuresis alarm and desmopressin treatments in the literature, most were conducted using old formulations of desmopressin.

OBJECTIVE

To compare the efficacy of desmopressin MELT formulation and enuresis alarm therapy in patients with MNE.

STUDY DESIGN

A total of 130 patients who had primary MNE were included in the study. The patients were divided into two groups using simple randomization; desmopressin MELT (Group 1, n = 66) and enuresis alarm (Group 2, n = 64). The patients were invited for a follow-up visit at the fourth, 12th and 24th weeks of treatment. Treatment response and compliance were evaluated using bed-wetting diary and ICSS criteria.

RESULTS

The mean age of the patients Group 1 and 2 was 11.2 + 3.3 and 10.2 + 3.4 years, respectively (p = 0.104). Complete response rate was similar at 4th week (53% vs. 37.3%, p = 0.162) and at 12th week (68.4% vs. 68.2%, p = 0.257). The relapse rate was significantly higher in the desmopressin MELT group than in the enuresis alarm group (48.9% vs 20.5%, p = 0.007). At the end of the study ten patients were excluded from the study because of loss to follow-up and/or side effects. The overall complete response rate was significantly higher in the enuresis alarm group than in the desmopressin MELT group at the end of the study (41.3% vs 64.9%, p = 0.035). When the intention to treat analysis population was considered, similarly the complete response rate was significantly higher in the enuresis alarm group than in the desmopressin MELT group (40.9% vs 64.1%, p = 0.027).

DISCUSSION

With regard to the management of children with MNE, our study revealed that desmopressin MELT and enuresis alarm both have high efficacy rates in primary MNE treatment both at 4th and 12th week. However, overall complete response rate was better in enuresis alarm treatment at 24th week. In addition, enuresis alarm treatment also presents as a more favorable relapse rate.

CONCLUSIONS

Enuresis alarm presented a more permanent treatment response and a lower relapse rate than desmopressin MELT formulation.

Pediatric Pharmacology of Desmopressin in Children with Enuresis: A Comprehensive Review

Desmopressin is a synthetic analogue of the natural antidiuretic hormone arginine vasopressin. Over the years, it has been clinically used to manage nocturnal polyuria in children with enuresis. Various pharmaceutical formulations of desmopressin have been commercialized for this indication-nasal spray, nasal drops, oral tablet and oral lyophilizate. Despite the fact that desmopressin is a frequently prescribed drug in children, its use and posology is based on limited pediatric data. This review provides an overview of the current pediatric pharmacological data related to the different desmopressin formulations, including their pharmacokinetics, pharmacodynamics and adverse events. Regarding the pharmacokinetics, a profound food effect on the oral bioavailability was demonstrated as well as different plasma concentration-time profiles (double absorption peak) of the desmopressin lyophilizate between adults and children. Literature about maturational differences in distribution, metabolism and excretion of desmopressin is rather limited. Regarding the pharmacodynamics, formulation/dose/food effect and predictors of response were evaluated. The lyophilizate is the preferred formulation, but the claimed bioequivalence in adults (200 µg tablet and 120 µg lyophilizate), could not be readily extrapolated to children. Prescribing the standard flat-dose regimen to the entire pediatric population might be insufficient to attain response to desmopressin treatment, whereby dosing schemes based on age and weight were proposed. Moreover, response to desmopressin is variable, whereby complete-, partial- and non-responders are reported. Different reasons were enumerated that might explain the difference in response rate to desmopressin observed: different pathophysiological mechanisms, bladder capacity and other predictive factors (i.e. breast feeding, familial history, compliance, sex, etc.). Also, the relapse rate of desmopressin treatment was high, rendering it necessary to use a pragmatic approach for the treatment of enuresis, whereby careful consideration of the position of desmopressin within this treatment is required. Regarding the safety of the different desmopressin formulations, the use of desmopressin was generally considered safe, but additional measures should be taken to prevent severe hyponatremia. To conclude the review, to date, major knowledge gaps in pediatric pharmacological aspects of the different desmopressin formulations still remain. Additional information should be collected about the clinical relevance of the double absorption peak, the food effect, the bioequivalence/therapeutic equivalence, the pediatric adapted dosing regimens, the study endpoints and the difference between performing studies at daytime or at nighttime. To fill in these gaps, additional well designed pharmacokinetic and pharmacodynamic studies in children should be performed.

Nocturnal enuresis: an update on management

Topics for DTB review articles are selected by DTB's editorial board to provide concise overviews of medicines and other treatments to help patients get the best care. Articles include a summary of key points and a brief overview for patients. Articles may also have a series of multiple choice CME questions.

Pharmacologic therapies for the management of non-neurogenic urinary incontinence in children

Introduction: Non-neurogenic urinary incontinence in children is a common condition that affects the quality of life for both patients and parents. Symptoms may occur in the daytime, nighttime, or both and may be the result of structural and functional anomalies. Evaluation and management of associated co-morbidities, such as constipation is critical to management. Behavioral therapy is a fist line therapy in most cases of non-neurogenic urinary incontinence and pharmacologic therapy a second-line therapy.Areas covered: In this review, the authors cover the pharmacologic agents, FDA approved and commonly used non-FDA approved, available for the treatment of four non-structural etiologies of non-neurogenic urinary incontinence in children. These include nocturnal enuresis, overactive bladder, giggle incontinence, and dysfunctional voiding.Expert opinion: Non-neurogenic causes of urinary incontinence in children represent a complicated medical condition that requires both pharmacologic and non-pharmacologic management. Limited FDA-approved therapies as well as suboptimal results with approved therapies due to a lack in the understanding of the underlying pathophysiology and patient selection may lead to the use of alternative non-FDA approved therapies.

Determination of the renal concentration capacity following intravenous administration of dDAVP in healthy humans

The synthetic AVP analogue 1-desamino-8-d-arginine-vasopressin (dDAVP) is used for treatment of polyuric disorders. Lack of commercially available assays limits the usefulness of dDAVP as a diagnostic tool in the assessment of renal concentrating capacity. We aimed to develop a specific radioimmunoassay (RIA) for determination of plasma dDAVP (pdDAVP) in order to investigate the relationship between pdDAVP levels and urine osmolality (Uosm). Further, we aimed to determine the onset, duration, and maximum concentrating capacity following intravenous (i.v.) bolus dDAVP injection. The dDAVP assay was based on a well-established RIA for measurements of AVP. Fourteen healthy subjects (aged 15-18 years) participated. Blood and urine samples were collected prior to and after i.v. bolus of 0.03 µg/kg dDAVP. Diuresis and Uosm was measured for nine hours following dDAVP administration. PdDAVP and Uosm were analyzed.We established a specific RIA for the measurement of pdDAVP. All subjects reached maximal pdDAVP concentration (C_max) 30 minutes following infusion, and a rise in Uosm after 60 minutes. Maximal Uosm varied between subjects, with no direct correlation to the achieved pdDAVP levels. We found no significant intra-individual variation between two dDAVP infusions and the effect was reproducible in terms of C_max and maximal Uosm. We characterized the relationship between pdDAVP and Uosm after dDAVP bolus injection in healthy adolescents using our dDAVP assay. Maximal Uosm achieved correlated with the baseline Uosm levels and seemed unrelated to achieved pdDAVP levels. The urine concentrating response was maintained at least eight hours.

Oral administration of diluted nasal desmopressin in managing neonatal central diabetes insipidus

BACKGROUND

Neonatal central diabetes insipidus (NCDI) remains a therapeutic challenge, as extremely low doses of enteral desmopressin cannot be titrated with current preparations. The aim of this study was to describe the use of orally administered dilute desmopressin in NCDI.

METHODS

Nasal desmopressin (100 μg/mL) was diluted in 0.9% saline to 10 μg/mL. Infants were treated with 1-5 μg and doses were titrated to a twice-daily regimen. The feed volume was 150 mL/kg/day and titrated according to weight gain.

RESULTS

Five infants aged 6-105 days were included. Stabilizing treatment doses ranged from 2 to 5 μg twice daily in neonates, and 12 μg twice daily in the older infant who was diagnosed at 105 days.

CONCLUSIONS

Dilution of nasal desmopressin with saline facilitates safe administration and dose titration in NCDI. We recommend considering this therapeutic approach to NCDI, particularly in small infants or where alternative treatment regimens have been unsuccessful.

Optimizing response to desmopressin in patients with monosymptomatic nocturnal enuresis

Most patients with monosymptomatic nocturnal enuresis can be effectively treated with an enuresis alarm or antidiuretic therapy (desmopressin), depending on the pathophysiology of the condition in the individual patient. Desmopressin is first-line therapy for enuresis caused by nocturnal polyuria, an excessive urine output during the night. However, in a recent study, around one-third of patients thought to be resistant to desmopressin were subsequently treated effectively with desmopressin monotherapy in a specialist centre. The aim of this article is to review best practice in selecting patients for desmopressin treatment, as well as outline eight recommendations for maximizing the chances of treatment success in patients receiving desmopressin. The roles of formulation, dose, timing of administration, food and fluid intake, inter-individual variation in response, body weight, adherence, withdrawal strategies and combination therapies are discussed in light of the most recent research on desmopressin and enuresis. Possible reasons for suboptimal treatment response are explored and strategies to improve outcomes in patients for whom desmopressin is an appropriate therapy are presented. Through optimization of the treatment plan in primary and specialist care centres, the hope is that fewer patients with this distressing and often embarrassing condition will experience unnecessary delays in receiving appropriate care and achieving improvements.

Advances in the management of primary monosymptomatic nocturnal enuresis in children

Intermittent incontinence of urine in a sleeping child who has previously been dry for less than 6 months without any other lower urinary tract symptoms is considered to be primary monosymptomatic nocturnal enuresis (PMNE). Although, most children outgrow PMNE with age, the psychological impact on the child warrants parental education and patient motivation and treatment. Motivational therapy, alarm therapy and drug therapy are the mainstay of treatment. Motivational and alarm therapy have better success rates than drug therapy alone. Desmopressin is the commonly used first-line drug and is best for short-term relief. Other drugs such as anti-cholinergics, imipramine and sertraline are used in resistant cases. This review focuses on the assessment and treatment of PMNE.

Diabetes insipidus: The other diabetes

Diabetes insipidus (DI) is a hereditary or acquired condition which disrupts normal life of persons with the condition; disruption is due to increased thirst and passing of large volumes of urine, even at night. A systematic search of literature for DI was carried out using the PubMed database for the purpose of this review. Central DI due to impaired secretion of arginine vasopressin (AVP) could result from traumatic brain injury, surgery, or tumors whereas nephrogenic DI due to failure of the kidney to respond to AVP is usually inherited. The earliest treatment was posterior pituitary extracts containing vasopressin and oxytocin. The synthetic analog of vasopressin, desmopressin has several benefits over vasopressin. Desmopressin was initially available as intranasal preparation, but now the oral tablet and melt formulations have gained significance, with benefits such as ease of administration and stability at room temperature. Other molecules used for treatment include chlorpropamide, carbamazepine, thiazide diuretics, indapamide, clofibrate, indomethacin, and amiloride. However, desmopressin remains the most widely used drug for the treatment of DI. This review covers the physiology of water balance, causes of DI and various treatment modalities available, with a special focus on desmopressin.

Formulations for children: problems and solutions

Paediatric formulation design is complex as there is a need to understand the developmental physiological changes that occur during childhood and their impact on the absorption of drugs. Paediatric dose adjustments are usually based on achieving pharmacokinetic or pharmacodynamic profiles equivalent to those achieved in adult populations. However, differences in the way in which children handle adult products or the use of bespoke paediatric formulations can result in unexpected pharmacokinetic drug profiles with altered clinical efficacy. Differences in drug formulations need to be understood by healthcare professionals involved in the prescribing, administration or dispensing of drugs to children such that appropriate advice is given to ensure that therapeutic outcomes are achieved. This issue is not confined to oral medicines but is applicable for all routes of administration encountered in paediatric therapy.

Combined laser acupuncture and desmopressin for treating resistant cases of monosymptomatic nocturnal enuresis: a randomized comparative study

OBJECTIVE

Monosymptomatic nocturnal enuresis (MNE) is a common sociomedical problem affecting children that may persist until adulthood despite various lines of therapy. The aim of this study was to assess the efficacy of combined laser acupuncture and desmopressin in managing patients with resistant MNE, compared with their efficacy when used as monotherapy.

MATERIAL AND METHODS

The study included 186 patients with a mean age of 15.7 years (range 10-21 years) presenting with persistent MNE. All patients were evaluated clinically and investigated with urine analysis, plain X-ray of the urinary tract and abdominal ultrasonography. They were randomized into three equal groups based on the line of management: group A, managed with laser acupuncture alone; group B, managed with desmopressin alone; and group C, managed with a combination of laser acupuncture and desmopressin, with a treatment course of 3 months and follow-up period of 6 months to record the efficacy of therapy, side-effects and bladder capacity.

RESULTS

A statistically significant higher cure rate was reported in group C patients, being reported in 33, 35 and 46 patients in groups A, B and C, respectively. Improvement was reported in 18, 17 and 13 cases in groups A, B and C, respectively, but the difference was not statistically significant. Bladder capacity significantly increased only in patients receiving acupuncture (groups A and C).

CONCLUSION

Combined laser acupuncture and desmopressin is a promising and valid option to manage resistant cases of MNE.

Desmopressin for the treatment of female storage lower urinary tract symptoms

Female storage lower urinary tract symptoms are prevalent and bothersome. They are usually attributed to an overactive bladder and treated with antimuscarinics. Nevertheless, failure of conventional treatment to alleviate nocturia in particular and epidemiological data suggesting that nocturnal polyuria is the only or a contributing factor to nocturia, has attracted interest in decreasing nighttime urine production as a method of managing nocturia. A reduction in urine production could also, at least temporarily, delay daytime storage symptoms by delaying bladder filling. Therefore, desmopressin, the synthetic analogue or naturally occurring antidiuretic hormone, could have a role in the management of female frequency, urgency and urgency incontinence. This work aims to review data on the use of desmopressin in females with storage symptoms. Available evidence indicates that desmopressin is efficacious in reducing nighttime urine production and episodes of nocturia, resulting in fewer sleep interruptions. This translates into improved quality of life. Desmopressin is also effective in postponing micturition, urgency and incontinence for several hours after being taken on demand. The tolerability profile of desmopressin is good and significantly improved compared to historical figures due to the introduction of new oral formulations, tailoring the dose according to gender and age and adhering to instructions for fluid restriction before administration. The incidence of hyponatremia, desmopressin’s most important side-effect, is less than 3% in recent trials. The efficacy of desmopressin, combined with its improved safety profile, makes it an interesting method for treating female storage lower urinary tract symptoms.

Pharmacokinetics of desmopressin administered as tablet and oral lyophilisate formulation in children with monosymptomatic nocturnal enuresis

Desmopressin 120 μg oral lyophilisate and 200 μg tablet are considered bioequivalent, based on extrapolation of studies in a limited number of adults and on one dose-finding study of desmopressin oral lyophilisate in children. However, no comparative pharmacokinetic study in children was executed confirming this statement. No data are available on the influence of food intake on the bioavailability of desmopressin tablet in a pediatric setting, although studies in adults have documented that food intake results in a significantly lower desmopressin plasma concentration. In this study, we analyzed plasma concentrations of desmopressin oral lyophilisate and tablet with concomitant food intake. Twenty-three children with monosymptomatic nocturnal enuresis (mean age, 12.7 years) were recruited. Two tests were performed on two separate days in identical conditions with a standardized food and fluid intake. Desmopressin was administered as desmopressin tablet or desmopressin oral lyophilisate immediately after a meal. Desmopressin plasma concentration was measured at 1 h, 2 h, and 6 h postdosing. No significant difference in plasma concentration of 120 μg desmopressin oral lyophilisate and 200 μg tablet was demonstrated, even with concomitant food intake. A significant difference in variability was found, identifying a smaller variance for desmopressin oral lyophilisate plasma concentrations at all time points. This study demonstrates comparable plasma levels for desmopressin oral lyophilisate, despite the lower dose. The dosage for desmopressin oral lyophilisate is more predictable due to the significantly smaller variance. Therefore, desmopressin oral lyophilisate seems more suitable, especially in the younger age group for which time interval between dinner and drug administration is limited.

Oral desmopressin lyophilisate (MELT) for monosymptomatic enuresis: structured versus abrupt withdrawal

OBJECTIVE

To investigate whether a structured withdrawal program from a sublingual formulation of fast-melting oral desmopressin lyophilisate (MELT) is superior to a sudden withdrawal from this formulation in the treatment of monosymptomatic nocturnal enuresis.

MATERIALS AND METHODS

One hundred and three children presented to our pediatric nephrology outpatient clinic for bedwetting. Eighty-one children, aged between 5½ and 14 years (mean age 8.64 years), were treated with MELT at a dosage of 120 mcg a day. Responders were randomized to been withdrawn from therapy, after 3 months, abruptly or in a structured withdrawal program (60 mcg/day for 15 days and then 60 mcg every second evening for another 15 days). Main outcome parameter was relapse rate 1 month after the end of treatment. Relapse was defined as bedwetting occurring more than 2 nights per month after the 1-month treatment-free period.

RESULTS

Relapse rate at 1 month after the end of treatment was 47.83% in the group on a structured program versus 45.83% in the abrupt termination group (p = 0.89).

CONCLUSION

Our study suggests that a structured withdrawal program from MELT therapy doesn't offer advantages compared to an abrupt termination in children with monosymptomatic nocturnal enuresis.

Desmopressin melt improves response and compliance compared with tablet in treatment of primary monosymptomatic nocturnal enuresis

Primary nocturnal enuresis is a prevalent childhood condition that can persist into adulthood. Desmopressin is an antidiuretic available as orally disintegrating lyophilisate (melt) or solid tablet. Recent findings suggesting different food interactions and clinical characteristics, including compliance, between desmopressin melt and tablet motivated a post hoc analysis of a previously reported randomised, crossover study. The efficacy of desmopressin melt compared with tablet was evaluated using the International Children's Continence Society (ICCS) responder definitions. Compliance was further analysed using detailed criteria, and the association between efficacy and compliance was examined. In total, 221 patients aged 5-15 years, already receiving desmopressin tablets were randomised to the treatment sequence melt (120/240 μg)/tablet (0.2/0.4 mg) or tablet/melt in two consecutive 3-week periods. The probability of being a responder (partial or full) during either period was significantly more likely with desmopressin melt compared with tablet (odds ratio, 2.0; confidence intervals, 1.07-3.73; p = 0.03). There was no period effect on compliance in the tablet/melt sequence and no difference in the number of completely compliant patients in each formulation group; however, more patients were >75 % compliant in period 1 compared with period 2 in the melt/tablet sequence. Increased compliance was associated with greater reductions in the number of wet nights for both formulations.

CONCLUSIONS

Desmopressin melt, compared with tablet, improves the probability of being a responder. Switching from tablet to melt formulation increased patient compliance. Increased compliance was associated with increased efficacy. Switching to desmopressin melt may benefit patients with suboptimal responses to desmopressin tablet.

Long-term durability of the response to desmopressin in female and male nocturia patients

AIMS

To explore the durability of efficacy and gender differences during chronic administration of desmopressin in nocturia.

METHODS

This pooled analysis of three short-term efficacy studies, with extensions, of desmopressin administered as orally disintegrating tablet (ODT) or solid tablet in nocturia treatment, comprised 351 patients completing 40-56 weeks' treatment. Efficacy endpoints of change in number of nocturnal voids and duration of initial undisturbed sleep period from baseline were analyzed to determine response durability and gender differences.

RESULTS

The mean decrease in number of nocturnal voids during short-term treatment was maintained and further reduced during the long term. At 52 weeks, the mean decrease in number of nocturnal voids from baseline reached 1.4-2.1 voids for desmopressin ODT 25-100 µg. Following 40-week tablet treatment, the decrease in number of nocturnal voids was 0.8-1.5 for desmopressin 100-400 µg. The mean decrease in nocturnal voids (25-50 µg ODT) was greater for females than males. For females, the improvement in initial period of undisturbed sleep was 2.5-3 hr for desmopressin ODT 25-100 µg, compared with 1.3-2.6 hr for males. No gender difference in efficacy was seen in the tablet studies.

CONCLUSIONS

The decrease in nocturnal voids and improvement in sleep with short-term desmopressin treatment were maintained throughout long-term treatment. A durable gender difference in efficacy in favor of females was observed with desmopressin ODT 25 µg. Further, large-scale long-term trials are needed to confirm the durability of efficacy with gender-specific doses of desmopressin.