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Context There is no licensed oral native testosterone (NT) because of challenges in the formulation. Licensed oral formulations of the ester, testosterone undecanoate (TU), require a meal for absorption and generate supraphysiological dihydrotestosterone (DHT) levels. Objective To develop an oral NT formulation. Design and methods A lipid-based formulation of native testosterone filled into soft-gelatin capsules at 40 mg per capsule was designed with 2 years of stability at ambient temperature. Pharmacokinetic comparison studies of this oral lipidic NT formulation to oral TU were conducted in dogs and hypogonadal men. Results In dogs, 40 mg NT was well absorbed under fasted conditions whereas 40 mg TU required a high-fat meal: for NT, the mean fed/fasted AUC ratio was 1.63 and for TU 7.05. In hypogonadal men, fed and fasted NT had similar pharmacokinetics: Cmax mean 26.5 vs 30.4 nmol/L (769 vs 882 ng/dL), AUC0–10 h 87 vs 88.6 h nmol/L. NT (fed state) showed a testosterone AUC increase of 45% between 120 and 200 mg, and NT 200 mg gave a similar mean AUC0–10 h to TU 80 mg: 87 vs 64.8 h nmol/L. Serum TU levels were variable and on a molar basis were ~ten-fold higher than serum testosterone levels after TU 80 mg fed. The DHT: testosterone AUC0–10 h ratio was more physiological for NT than TU being 0.19 vs 0.36. There were no emerging safety concerns with NT. Conclusion This novel oral lipidic native testosterone formulation has potential advantages over oral TU of dosing independently of food and a lower risk of supraphysiological DHT levels. Significance statement There is no licensed oral testosterone because of challenges in formulation, and the oral formulations of the ester, testosterone undecanoate, require a fatty meal for absorption and generate supraphysiological dihydrotestosterone levels. We have overcome the design challenges and formulated an oral native testosterone that can be taken with or without food and provides physiological levels of testosterone and dihydrotestosterone in hypogonadal men. This formulation, DITEST, has the potential advantage of being oral for patients who do not tolerate injections and less risk of adverse events that might theoretically be associated with elevated dihydrotestosterone levels. Future studies will need to define the dosing regimen for replacement in hypogonadal men.

Steroid 5β-reductase (AKR1D1) is highly expressed in human liver where it inactivates endogenous glucocorticoids and catalyses an important step in bile acid synthesis. Endogenous and synthetic glucocorticoids are potent regulators of metabolic phenotype and play a crucial role in hepatic glucose metabolism. However, the potential of synthetic glucocorticoids to be metabolised by AKR1D1 as well as to regulate its expression and activity has not been investigated. The impact of glucocorticoids on AKR1D1 activity was assessed in human liver HepG2 and Huh7 cells; AKR1D1 expression was assessed by qPCR and Western blotting. Genetic manipulation of AKR1D1 expression was conducted in HepG2 and Huh7 cells and metabolic assessments were made using qPCR. Urinary steroid metabolite profiling in healthy volunteers was performed pre- and post-dexamethasone treatment, using gas chromatography-mass spectrometry. AKR1D1 metabolised endogenous cortisol, but cleared prednisolone and dexamethasone less efficiently. In vitro and in vivo, dexamethasone decreased AKR1D1 expression and activity, further limiting glucocorticoid clearance and augmenting action. Dexamethasone enhanced gluconeogenic and glycogen synthesis gene expression in liver cell models and these changes were mirrored by genetic knockdown of AKR1D1 expression. The effects of AKR1D1 knockdown were mediated through multiple nuclear hormone receptors, including the glucocorticoid, pregnane X and farnesoid X receptors. Glucocorticoids down-regulate AKR1D1 expression and activity and thereby reduce glucocorticoid clearance. In addition, AKR1D1 down-regulation alters the activation of multiple nuclear hormone receptors to drive changes in gluconeogenic and glycogen synthesis gene expression profiles, which may exacerbate the adverse impact of exogenous glucocorticoids.

Objectives There is no licensed, dose-appropriate formulation of hydrocortisone for children with adrenal insufficiency (AI) and patients rely on compounded adult medication. The aim of this study was to evaluate the absorption, palatability and safety of Infacort®, an immediate-release, granule formulation of hydrocortisone with taste masking. Study design Single site with satellites attended by a “flying” doctor from investigator site. Open-label, single-dose study in three consecutive child cohorts (n=24) with AI; Cohort 1, children aged 2 to Au: the age ranges quoted are slightly different in each of the abstract, main text, Table 1 and Supplemental table. These have now been unified as shown here. . Methods Fasted children were given a single dose of Infacort® as dry granules administered directly from a capsule or spoon followed by a drink. The primary endpoint was the maximum serum cortisol concentration up to 240 minutes after Infacort® administration. Secondary endpoints were palatability and adverse events (AEs). Results All children showed an increase in cortisol above baseline after Infacort® (p

Context:The classic androgen synthesis pathway proceeds via DHEA, androstenedione and testosterone to 5α-dihydrotestosterone (DHT). However, DHT synthesis can also be achieved by an alternative pathway originating from 17α-hydroxyprogesterone (17OHP), which accumulates in congenital adrenal hyperplasia (CAH). Similarly, recent work has highlighted androstenedione-derived 11-oxygenated 19-carbon steroids as active androgens and, in CAH, androstenedione is generated directly from 17OHP. The exact contribution of alternative pathway activity to androgen excess in CAH and its response to glucocorticoid therapy is unknown.Objective:We sought to quantify classic and alternative pathway-mediated androgen synthesis in CAH, their diurnal variation and their response to conventional glucocorticoid (GC) therapy and modified release hydrocortisone.Methods:We employed urinary steroid metabolome profiling by gas chromatography-mass spectrometry for 24-h steroid excretion analysis, studying the impact of conventional GC...

Current treatment in Europe for adrenal insufficiency in neonates and infants is unsatisfactory as unlicensed adult dosage formulations are used. These are difficult to administer and may give rise to inconsistencies in dose as the content uniformity of the dosage form cannot be verified. As there is no licensed hydrocortisone formulation for children < 6 years hydrocortisone is often compounded by pharmacies using adult hydrocortisone tablets. In a recent study of compounded hydrocortisone up to 20% of the batches did not meet European Pharmacopeial accuracy and precision criteria (ECE 2014 Abstract #1278). This medication safety study investigated hydrocortisone individually and extemporaneously compounded for paediatric use in adrenally insufficient patients, meaning the current therapy is inadequate in up to every 5th child treated. Thus, there is a need for specifically designed and licensed hydrocortisone formulations for this vulnerable paediatric patient group especially neonates and infants.