Bioequivalence of a new liquid formulation of ursodeoxycholic acid (Ursofalk suspension) and Ursofalk capsules measured by plasma pharmacokinetics and biliary enrichment

Fetal cardiac dysfunction in intrahepatic cholestasis of pregnancy is associated with elevated serum bile acid concentrations

BACKGROUND & AIMS

Intrahepatic cholestasis of pregnancy (ICP) is associated with an increased risk of stillbirth. This study aimed to assess the relationship between bile acid concentrations and fetal cardiac dysfunction in patients with ICP who were or were not treated with ursodeoxycholic acid (UDCA).

METHODS

Bile acid profiles and NT-proBNP, a marker of ventricular dysfunction, were assayed in umbilical venous serum from 15 controls and 76 ICP cases (36 untreated, 40 UDCA-treated). Fetal electrocardiogram traces were obtained from 43 controls and 48 ICP cases (26 untreated, 22 UDCA-treated). PR interval length and heart rate variability (HRV) parameters were measured in 2 behavioral states (quiet and active sleep).

RESULTS

In untreated ICP, fetal total serum bile acid (TSBA) concentrations (r = 0.49, p = 0.019), hydrophobicity index (r = 0.20, p = 0.039), glycocholate concentrations (r = 0.56, p = 0.007) and taurocholate concentrations (r = 0.44, p = 0.039) positively correlated with fetal NT-proBNP. Maternal TSBA (r = 0.40, p = 0.026) and alanine aminotransferase (r = 0.40, p = 0.046) also positively correlated with fetal NT-proBNP. There were no significant correlations between maternal or fetal serum bile acid concentrations and fetal HRV parameters or NT-proBNP concentrations in the UDCA-treated cohort. Fetal PR interval length positively correlated with maternal TSBA in untreated (r = 0.46, p = 0.027) and UDCA-treated ICP (r = 0.54, p = 0.026). Measures of HRV in active sleep and quiet sleep were significantly higher in untreated ICP cases than controls. HRV values in UDCA-treated cases did not differ from controls.

CONCLUSIONS

Elevated fetal and maternal serum bile acid concentrations in untreated ICP are associated with an abnormal fetal cardiac phenotype characterized by increased NT-proBNP concentration, PR interval length and HRV. UDCA treatment partially attenuates this phenotype.

LAY SUMMARY

The risk of stillbirth in intrahepatic cholestasis of pregnancy (ICP) is linked to the level of bile acids in the mother which are thought to disrupt the baby's heart rhythm. We found that babies of women with untreated ICP have abnormally functioning hearts compared to those without ICP, and the degree of abnormality is closely linked to the level of harmful bile acids in the mother and baby's blood. Babies of women with ICP who received treatment with the drug UDCA do not have the same level of abnormality in their hearts, suggesting that UDCA could be a beneficial treatment in some ICP cases, although further clinical trials are needed to confirm this.

Pharmaceutical suspensions of ursodeoxycholic acid for pediatric patients: in vitro and in vivo studies

Ursodeoxycholic acid (UDCA) is used in the oral therapy of hepatobiliary cholestatic diseases. Due to UDCA low aqueous solubility, two pediatric oral suspensions (25 mg/mL) were formulated with a few excipients, suspension A (SA) and suspension B (SB) with a vehicle, including two suspending agents. Physical, chemical and microbiological stability and a rheological study were performed at three different conditions (5 °C ± 3 °C, 25 °C ± 2 °C/60% RH ± 5% RH and 40 °C ± 2 °C/75% RH ± 5% RH) for 120 days. Moreover, dissolution study, content uniformity, related substances, and a study of relative oral bioavailability were also carried out. Both suspensions were physically, chemically and microbiologically stable throughout the study. SA and SB can be stored at 25 °C and 5 °C for at least 120 days whereas SA can be kept at 40 °C for at least 90 days and SB for 120 days. They both met USP specifications for dissolution, content uniformity, and related substances. SA and SB showed an improved relative oral bioavailability compared to the solid dosage form and they both displayed similar relative oral bioavailability with no significant differences between them. The developed suspensions proved to be safe and adequate and they are ideal for pediatric use for their acceptability, accurate dose administration and treatment adherence.

Development and validation of a new HPLC method for the analysis of a novel oral suspension formulation of 50 mg/ml ursodeoxycholic acid for newborns

Objectives

Drugs are developed for adults, making it difficult to find suitable treatments for children. Hospital pharmacy has developed alternatives to respond to this medical need. The objective of this study is to present a new liquid formulation of ursodeoxycholic acid (UDCA) at a concentration suitable for treatment of neonatal jaundice, and to introduce a novel high pressure liquid chromatography (HPLC) assay method.

Methods

Four formulations have been developed using suspension vehicles due to the low solubility of the active ingredient, and different concentrations of excipient, xanthan gum, needed to facilitate resuspension. An HPLC method coupled to a diode array detector (DAD) has been developed. This method was used to analyze chemical and microbiologic stabilities, as well as physicochemical properties and palatability.

Results

After formulation was chosen, our new HPLC method assay was developed and validated for the quantification of chemical and microbiological stabilities of our product. Both parameters were stable over three months. Palatability has been improved thanks to the addition of universal suspension adjuvants. Odor, appearance and taste were judged pleasant despite a bitter aftertaste, with a persistence of the UDCA resuspension after one month.

Conclusions

Three months after informing neonatal department about the availability of the drug, patients and caregivers are satisfied, and production campaigns are routinely planned.

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.

Applications of accelerator MS in pediatric drug evaluation

Accelerator MS (AMS) provides a novel method for obtaining and analyzing pharmacokinetics and pharmacodynamics in children. This paper reviews the scientific and ethical rationale for AMS in pediatric trials, the regulatory framework and general considerations with some specific examples of pediatric clinical trials using AMS. Microdosing in the context of this article refers to studies using a negligible amount (nanocuries) of (14)C as tracer, and AMS as a quantitative technique. The technology is by no means a panacea for the deficiency in pediatric clinical research; however, it lessens the challenges and provides the most quantitative tool for pediatric pharmacology studies.