A Phase 2/3 interventional study of Atumelnant and Placebo in Congenital Adrenal Hyperplasia and Classic Congenital Adrenal Hyperplasia, sponsored by Crinetics Pharmaceuticals Inc.. Recruiting at 53 sites in 13 countries. Open to participants aged 1 Year to 17 Years. Per ClinicalTrials.gov, last updated 2026-11-10.
Sponsored by Crinetics Pharmaceuticals Inc. (part of Vertex Pharmaceuticals Incorporated) · Phase 2/3, Interventional, and Treatment
The purpose of this study is to evaluate the safety, efficacy, pharmacokinetics (PK), and pharmacodynamics (PD) of atumelnant treatment in pediatric participants with classic congenital adrenal hyperplasia (CAH).
This Phase 2/3 plus open-label extension study is designed to evaluate the safety, efficacy, pharmacokinetics (PK), and pharmacodynamics (PD) of atumelnant treatment in pediatric participants with classic CAH. Part A is a Phase 2, open-label, semi-sequential cohorts portion of the study. Part B is the Phase 3, double-blind, randomized, placebo controlled confirmatory portion of the study. Part C is the open-label extension (OLE) portion of the study. Participants in Part A and B are eligible to enroll in Part C (OLE).
A total of approximately 153 participants may be enrolled in the study (planned and optional cohorts) ages 1 to \< 18 years old.
The first 3 cohorts in Part A are for ages 12 to \<18 years and will be semi-sequential, and Safety Review Committee (SRC) review of data and approval to proceed is required prior to enrolling each subsequent cohort. The fourth cohort in Part A is for ages 1 to 11 years old and will begin after Cohorts 1 and 2 have been completed, additional requirements are fulfilled, and following SRC review of Cohorts 1 and 2 data.
101 studies on the registry are indexed under Adrenal Hyperplasia, Congenital; 28 are open to participants now.
This study's planned enrollment of 153 is above the median of 37 across 50 interventional studies indexed under Adrenal Hyperplasia, Congenital.
Browse Adrenal Hyperplasia, Congenital studies →Crinetics Pharmaceuticals Inc. is the lead sponsor of 19 studies on the registry; 3 are open to participants now.
Of its 12 completed or terminated interventional studies of FDA-regulated products, 6 (50%) have results posted.
First submitted before Crinetics Pharmaceuticals Inc. became part of Vertex Pharmaceuticals Incorporated.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Part A and B participants are eligible to be included in the study only if all of the following criteria apply:
Part C inclusion criteria require participants to complete treatment in either Part A or Part B and in the Investigator's opinion it would benefit the participant to continue in Part C, regardless of age.
Exclusion Criteria:
Part A and Part B: Individuals in Part A and Part B who meet any of the following criteria will be excluded from participation in this study:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ULN (upper limit of normal)
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Open-label, semi-sequential cohorts.
Drug: Atumelnant
Randomized, Parallel Arms, Double-Blind
Drug: Atumelnant
Randomized, Parallel Arms, Double-Blind
Drug: Placebo
Open-label treatment period for participants entering Part C from Part A and B.
Drug: Atumelnant
Atumelnant, tablets, once daily by mouth, weight-based dosing
Also known as: CRN04894
Placebo, tablets, once daily by mouth, weight-based dosing
Change from baseline in morning serum androstenedione (A4) (Part A)
Time frame: Week 8
Percent change from baseline in glucocorticoid (GC) daily dose while serum early morning A4 ≤Upper Limit of Normal (ULN) (Part B)
Time frame: Week 28
Change from baseline in serum early morning A4 over time (Part C)
Time frame: Up to Week 260
Change from baseline in morning serum 17-hydroxyprogesterone (17-OHP) (Part A)
Time frame: Week 8
Plasma and/or blood concentrations of atumelnant (Part A)
Time frame: Up to Week 8
Change from baseline in serum early morning A4 (Part B)
Time frame: Week 4
Change from baseline in serum early morning 17-OHP (Part B)
Time frame: Week 4
Proportion of participants with physiologic GC dose while serum early morning A4 ≤ULN (Part B)
Time frame: Week 28
Change from baseline in serum early morning 17-OHP over time (Part C)
Time frame: Up to Week 260
Percent change from baseline in GC daily dose over time (Part C)
Time frame: Up to Week 260
Proportion of participants with physiologic GC dose while serum early morning A4 ≤ULN over time (Part C)
Time frame: Up to Week 260
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Plan to share: No
No publications or documents are linked to this record.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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Studies of the drug tested here: Atumelnant
Adrenal Hyperplasia, Congenital →
Crinetics Pharmaceuticals Inc. →