A Phase 1 interventional study of Chronocort® and Cortef® in Adrenal Insufficiency, sponsored by Neurocrine UK Limited. Completed at 1 site in United Kingdom. Open to male participants aged 18 Years to 45 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-09-14.
Sponsored by Neurocrine UK Limited · Phase 1, Interventional, and Treatment
This was a single centre, open label, randomised, two period, crossover study to evaluate the bioavailability of Chronocort® versus Cortef® immediate release hydrocortisone tablets in dexamethasone-suppressed healthy adult male subjects.
This study was an open-label, randomised, single dose, two-period, crossover study in 25 healthy male subjects.
The study comprised of a pre-study screen, followed by 2 treatment periods (1 and 2) and a post-study followup.
Screening (Day -28 to Day -1): Screening assessments were carried out within 28 days before first administration of IMP. Eligible subjects were asked to return for the treatment periods. Continued eligibility was confirmed pre-dose during each treatment period.
Treatment Periods (Day -1 to Day 1): Eligible subjects received a single-dose of each IMP over 2 treatment periods (1/period as determined by the randomisation schedule), each separated by 7 days washout. Each study period was approximately 2 days in duration, from the afternoon of Day -1 to the morning of Day 1 at 24 hours (h) post-dose. During each treatment period, Subjects arrived at the Clinical Unit on Day -1, IMP was administered on the morning of Day 0 fasted (following an overnight fast of at least 10 h) and subjects were discharged following the 24 h post-dose blood samples and completion of the scheduled measurements.
Pharmacokinetic (PK) samples were collected pre-dose at \~ -2min and up to 23 h post-dose (Day 1) (24 samples) for the measurement of cortisol. A further 3 baseline samples were taken for the measurement of cortisol. Safety was also evaluated throughout the study.
Post Study: After completion of both study periods, the subjects returned 4-22 days later for the final followup visit.
Subjects (unless anatomically sterile or where abstaining from sexual intercourse is in line with the preferred and usual lifestyle of the subject) and sexual partners must use 2 effective contraception methods during the trial and for 3 months after the last dose, for example:
Exclusion Criteria:
Single dose of 20mg Chronocort® (oral administration), followed by a single dose of 20mg Cortef® Immediate Release Hydrocortisone Tablets (oral administration).
Drug: Chronocort® · Drug: Cortef®
Single dose of 20mg Cortef® Immediate Release Hydrocortisone Tablets (oral administration), followed by a single dose of 20mg Chronocort® (oral administration).
Drug: Chronocort® · Drug: Cortef®
Single dose of 20mg Chronocort® administered in one treatment period
Single dose of 20mg Cortef® administered in one treatment period
Area under the concentration time curve from time 0 to infinity (AUC0-inf) of Chronocort® to Cortef® based on baseline adjusted and unadjusted serum cortisol concentration calculated for each sampling time point.
Comparing the area under the concentration time curve of Chronocort® compared to Cortef® immediate release hydrocortisone tablets.
Time frame: Samples taken at 0, 0.25, 0.5, 0.75, 1.0, 1.25, 1.5, 2, 2.5, 3, 4, 5, 6, 8, 10, 11,12, 13, 14, 16, 18, 20, 22, and 24 hours (morning of Day 1) in both periods.
Pharmacokinetic parameters for serum cortisol + relative bioavailability - Cmax
The following PK endpoint was derived from baseline adjusted and unadjusted serum cortisol concentration-time data following administration of each IMP. ◦ Cmax Maximum plasma cortisol concentration.
Time frame: Samples taken at 0, 0.25, 0.5, 0.75, 1.0, 1.25, 1.5, 2, 2.5, 3, 4, 5, 6, 8, 10, 11,12, 13, 14, 16, 18, 20, 22, and 24 hours (morning of Day 1) in both periods.
Pharmacokinetic parameters for serum cortisol + relative bioavailability - Tmax
The following PK endpoint was derived from baseline adjusted and unadjusted serum cortisol concentration-time data following administration of each IMP. ◦ Tmax The time to maximum observed cortisol concentration sampled during a dosing interval.
Time frame: Samples taken at 0, 0.25, 0.5, 0.75, 1.0, 1.25, 1.5, 2, 2.5, 3, 4, 5, 6, 8, 10, 11,12, 13, 14, 16, 18, 20, 22, and 24 hours (morning of Day 1) in both periods.
Pharmacokinetic parameters for serum cortisol + relative bioavailability - Kel
The following PK endpoint was derived from baseline adjusted and unadjusted serum cortisol concentration-time data following administration of each IMP. ◦ kel Elimination rate constant.
Time frame: Samples taken at 0, 0.25, 0.5, 0.75, 1.0, 1.25, 1.5, 2, 2.5, 3, 4, 5, 6, 8, 10, 11,12, 13, 14, 16, 18, 20, 22, and 24 hours (morning of Day 1) in both periods.
Pharmacokinetic parameters for serum cortisol + relative bioavailability - t1/2
The following PK endpoint was derived from baseline adjusted and unadjusted serum cortisol concentration-time data following administration of each IMP. ◦ t1/2 Terminal half-life.
Time frame: Samples taken at 0, 0.25, 0.5, 0.75, 1.0, 1.25, 1.5, 2, 2.5, 3, 4, 5, 6, 8, 10, 11,12, 13, 14, 16, 18, 20, 22, and 24 hours (morning of Day 1) in both periods.
Pharmacokinetic parameters for serum cortisol + relative bioavailability - AUC0-t
The following PK endpoint was derived from baseline adjusted and unadjusted serum cortisol concentration-time data following administration of each IMP. ◦ AUC0-t Area under the plasma cortisol concentration-time curve (AUC) from the time of dosing to the time of the last observed concentration.
Time frame: Samples taken at 0, 0.25, 0.5, 0.75, 1.0, 1.25, 1.5, 2, 2.5, 3, 4, 5, 6, 8, 10, 11,12, 13, 14, 16, 18, 20, 22, and 24 hours (morning of Day 1) in both periods.
Pharmacokinetic parameters for serum cortisol - Serum cortisol clearance (CL/F)
Calculated as Dose / AUC0-inf. This PK endpoint was derived from baseline adjusted and unadjusted serum cortisol concentration-time data following administration of each IMP.
Time frame: Samples taken at 0, 0.25, 0.5, 0.75, 1.0, 1.25, 1.5, 2, 2.5, 3, 4, 5, 6, 8, 10, 11,12, 13, 14, 16, 18, 20, 22, and 24 hours (morning of Day 1) in both periods.
Pharmacokinetic parameters for serum cortisol - Distribution during terminal elimination (Vz/F)
Volume of distribution based on the terminal elimination phase following extravascular administration derived from baseline adjusted and unadjusted serum cortisol
Time frame: Samples taken at 0, 0.25, 0.5, 0.75, 1.0, 1.25, 1.5, 2, 2.5, 3, 4, 5, 6, 8, 10, 11,12, 13, 14, 16, 18, 20, 22, and 24 hours (morning of Day 1) in both periods.
Observed changes in Safety Laboratory Data
Observed changes in Safety Laboratory data (biochemistry, haematology \& urinalysis) during the course of the study, with any out of normal range values flagged.
Time frame: Screening, Pre-dose and 10h and 24h post-dose during both treatment periods; Follow up
Observed changes in Vital Signs
Observed changes in vital signs data (blood pressure, pulse rate and oral temperature) during the course of the study, with any out of normal range values flagged.
Time frame: Screening; Pre-dose and at 4 and 10h post-dose during both treatment periods; Follow up
Observed changes in Electrocardiogram (ECG) data during the course of the study
12-Lead ECG parameters (Heart Rate, PR interval, QRS width, QT interval, and QT interval corrected using Bazett's formula (QTcB)) and investigator clinical interpretation was listed with any out of normal range values flagged.
Time frame: Screening, Pre-dose and 10h post-dose during both treatment periods; Follow up
Adverse Events
Adverse events (AEs) observed throughout the study
Time frame: Through study completion - approximately 6 weeks
Plan to share: No
No publications or documents are linked to this record.
This study is completed, as verified in Sep 2026. You cannot join it, but the record below documents what was studied.
Get an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Neurocrine UK Limited