A Study Testing Atumelnant Compared to Placebo in Adults with Classic Congenital Adrenal Hyperplasia to Reduce Steroid Dose While Controlling Hormones

3 1

What is this study about?

This study is looking at a condition called classic congenital adrenal hyperplasia, which is a disorder where the adrenal glands do not produce certain hormones properly. People with this condition need to take replacement hormones called glucocorticoids to help their body function normally. The treatment being tested in this study is called atumelnant, which comes in tablet form and is taken by mouth. The study will compare atumelnant with placebo to see which works better. Atumelnant is also known by its code name CRN04894.

The purpose of this study is to find out if atumelnant can help reduce the daily dose of glucocorticoid medication that people with this condition need to take, while still keeping the levels of certain hormones called adrenal androgens under control. The study will measure hormone levels in the blood, including a hormone called androstenedione and another one called 17-hydroxyprogesterone, to see if the treatment is working. The study will also look at how safe atumelnant is and what side effects it might cause.

The study will last for 32 weeks of treatment, and participants will be randomly assigned to receive either atumelnant tablets or placebo tablets. During the study, doctors will regularly check hormone levels in the blood and may adjust the dose of glucocorticoid medication based on these results. Participants will need to continue taking their regular glucocorticoid replacement medication throughout the study, and if they take a medication called fludrocortisone for mineral balance, they will continue that as well. The study will involve multiple visits to the study site for blood tests and health checks to monitor how well the treatment is working and to watch for any problems.

1 Treatment Period

This period will last for 32 weeks.

You will receive either atumelnant or a placebo (an inactive substance that looks like the study medication but contains no active ingredient). The assignment will be random, and neither you nor your doctor will know which one you are receiving.

Atumelnant is available in two strengths: 80 mg tablets and 120 mg tablets. Both are taken by mouth.

During this period, your daily dose of glucocorticoid (a type of steroid hormone replacement medication, such as hydrocortisone, prednisolone, prednisone, methylprednisolone, or dexamethasone) may be adjusted. The goal is to reduce the amount of glucocorticoid you take while keeping your hormone levels balanced.

You will continue taking your regular glucocorticoid medication as prescribed by your doctor throughout the study.

If you are taking fludrocortisone (a medication to help balance salt and water in your body), you will continue at your current stable dose.

If you are on estrogen therapy, you will continue at your current stable dose.

2 Study Visits and Monitoring

You will have regular visits to the study site throughout the 32-week treatment period.

At Week 2, your blood will be tested to measure androstenedione (A4), a hormone that is often elevated in people with congenital adrenal hyperplasia.

At Week 32, your blood will be tested again to measure androstenedione (A4) and 17-hydroxyprogesterone (17-OHP), another hormone related to your condition.

Blood samples will be taken in the morning, both before and after you take your glucocorticoid dose, to see how well the treatment is working.

Your doctor will monitor your hormone levels and may adjust your glucocorticoid dose based on the results.

Your blood sodium and potassium levels will be checked to ensure they remain in the normal range.

3 Contraception Requirements During the Study

If you are a female who can become pregnant and engage in sexual intercourse with men, you must use a highly effective method of birth control from the start of the study until at least 2 weeks after your last dose of study medication.

If you are a male who engages in sexual intercourse with women who can become pregnant, you must use a condom from the start of the study until at least 2 weeks after your last dose of study medication, unless you have had a vasectomy with confirmed absence of sperm.

If you are a male participant, you must agree not to donate sperm during the study and until at least 2 weeks after your last dose of study medication.

4 Follow-up Period

After completing the 32-week treatment period, you will be monitored for at least 2 weeks after your last dose of study medication.

This follow-up period ensures that any effects of the medication are properly observed after treatment ends.

Who Can Join the Study?

You must be 18 years of age or older but younger than 75 years at the time of signing the consent form
You must be willing and able to follow the study procedures and take the study treatment as directed
You must have classic congenital adrenal hyperplasia (a condition where the adrenal glands do not make certain hormones properly) caused by 21-hydroxylase deficiency (a specific enzyme problem), confirmed by your doctor
Your morning blood test for androstenedione (a hormone called A4) must show one of these patterns: levels above the normal upper limit while taking low doses of glucocorticoid (a steroid hormone medication) equivalent to less than 11 milligrams per square meter of body surface per day in hydrocortisone units, OR normal A4 levels in the upper half of the normal range while taking 15 milligrams per square meter of body surface per day or more of glucocorticoid in hydrocortisone units, OR A4 levels above the normal upper limit while taking 11 milligrams per square meter of body surface per day or more of glucocorticoid in hydrocortisone units
You must be on a stable dose of glucocorticoid replacement therapy (such as hydrocortisone, prednisolone, prednisone, methylprednisolone, or dexamethasone) with no dose changes greater than a specific amount within 2 months before joining the study
If you are taking fludrocortisone (a medication to replace another hormone called mineralocorticoid), your dose must have been stable for at least 2 months before joining the study, you must not have orthostatic hypotension (dizziness when standing up due to low blood pressure), and your blood sodium and potassium levels must be normal
If you are taking estrogen therapy (female hormone treatment) by any method, your dose must have been stable for at least 3 months before joining the study
If you are a female who has sexual intercourse with men, you must either be unable to become pregnant because of surgery (removal of the uterus, fallopian tubes, or ovaries), OR agree to use highly effective birth control methods from the start of the study until at least 2 weeks after the last dose of study medication
If you are a male who has sexual intercourse with women, you must agree to use a condom when sexually active with a female partner who can become pregnant from the start of the study until at least 2 weeks after the last dose of study medication, OR have had a vasectomy with confirmed absence of sperm, OR agree to remain abstinent throughout the study and until at least 2 weeks after the last dose
If you are male, you must agree not to donate sperm during the study and until at least 2 weeks after the last dose of study medication

Who Cannot Join the Study?

The study information provided does not contain specific exclusion criteria details
Exclusion criteria are the reasons why a person cannot join this clinical trial, which is a research study that tests new treatments
Without detailed exclusion criteria information, it is not possible to list the specific conditions or situations that would prevent participation in this study
Typical exclusion criteria in clinical trials may include things like other medical conditions, certain medications being taken, pregnancy status, or previous treatments, but these specific details are not available in the provided study information

Where you can join this trial?

Verified and Recommended Sites

No sites found in this category

Verified Sites

Site Name	City	Country
Medical University Of Vienna	Vienna	Austria
Azienda Ospedaliera Universitaria Federico II Di Napoli	Naples	Italy
Centre Hospitalier Universitaire De Bordeaux	Bordeaux	France
IRCCS Humanitas Research Hospital	Rozzano	Italy

Other Sites

Site Name	City	Country
Azienda Ospedaliera di Padova	Padua	Italy
Ospedale San Raffaele S.r.l.	Milan	Italy
Karolinska University Hospital	Solna	Sweden
IRCCS Ospedale Policlinico San Martino	Genoa	Italy
Uniwersyteckie Centrum Stomatologii I Medycyny Specjalistycznej Sp. z o.o.	Poznan	Poland
Azienda Ospedaliero Universitaria Di Modena	Modena	Italy
Azienda Ospedaliera Universitaria Policlinico Paolo Giaccone	Palermo	Italy
Instytut Centrum Zdrowia Matki Polki	Lodz	Poland
Samodzielny Publiczny Zaklad Opieki Zdrowotnej Szpital Uniwersytecki W Krakowie	Cracow	Poland
Centre Hospitalier Universitaire De Nantes	Nantes	France
Centre Hospitalier Lyon Sud	Pierre Benite	France
Hopital Beaujon	Clichy	France
Queen Silvia Childrens Hospital – Sahlgrenska University Hospital – Vaestra Goetalandsregionen	Gothenburg	Sweden
Centrum Zdrowia MDM	Warsaw	Poland
Mezfkmxgo Mwchrpu gmjsq	Munich	Germany
Kgwkevve dck Uyrnnpeqergr Mmhiqexn Aeo	Munich	Germany
Uuhauuhzodrwkcevtaevx Eneli Axn	Essen	Germany
Lwhik Ujoadfhxekwr Mplrlcp Cuyspxt (wxcfe	Leiden	The Netherlands
Uyljddylxv Dcpsr Sslan Db Rncw Ls Sifwqlkz	Rome	Italy
Cdfknx Hifcwkurorn Rtvakgph Daiqpcelfyfzqc	Angers	France
Cnni Dn Nhjvl	Vandoeuvre Les Nancy	France
Uyukaankfbwnqhrskqihm Wtnlrmhgd Azw	Wuerzburg	Germany
Ihndp Obhrqcqy Aqbjprbkbv Sdy Lghe	Milan	Italy

Trial status

Country	Status	Recruitment Start
Austria	Recruiting	03.12.2025
France	Recruiting	03.12.2025
Germany	Recruiting	03.12.2025
Italy	Recruiting	03.12.2025
Poland	Recruiting	03.12.2025
Sweden	Recruiting	03.12.2025
The Netherlands	Not yet recruiting	03.12.2025

Trial locations

Investigated drugs:

ATUMELNANT

Atumelnant is an investigational medication being studied in this trial. It is being tested to see if it can help reduce the amount of daily glucocorticoid (a type of steroid medication) that patients need to take while still keeping their hormone levels under control. This medicine is being compared to a placebo to determine if it is safe and effective for treating adults with classic congenital adrenal hyperplasia, a condition where the adrenal glands do not produce certain hormones properly.

Investigated diseases:

Adrenogenital syndrome

Classic Congenital Adrenal Hyperplasia – Classic Congenital Adrenal Hyperplasia is a genetic disorder that affects the adrenal glands, which are small organs located above the kidneys. The condition occurs when the body cannot produce enough of certain hormones, particularly cortisol, due to enzyme deficiencies. As a result, the adrenal glands become enlarged and produce excessive amounts of male hormones called androgens. This hormonal imbalance begins before birth and continues throughout life if not managed. People with this condition may experience abnormal development of sexual characteristics, growth problems, and difficulties in maintaining proper salt and water balance in the body. The disorder is inherited in an autosomal recessive pattern, meaning both parents must carry the genetic mutation for a child to develop the condition.

Trial ID:

2024-519579-24-00

Protocol code:

CRN04894-12

Trial Phase:

Therapeutic confirmatory (Phase III)

Other Trials to Consider

#1 Clinical Trials Search in Europe

A Study Testing Atumelnant Compared to Placebo in Adults with Classic Congenital Adrenal Hyperplasia to Reduce Steroid Dose While Controlling Hormones

What is this study about?

Who Can Join the Study?

Who Cannot Join the Study?