An Extension Study to Evaluate Safety and Efficacy of Atumelnant in Participants With Congenital Adrenal Hyperplasia (CALM2-CAH)

June 24, 2026 updated by: Crinetics Pharmaceuticals Inc.

An Open-label, Long-term Extension Study to Evaluate Safety and Efficacy of Atumelnant in Participants With Congenital Adrenal Hyperplasia (CALM2-CAH)

The purpose of this study is to evaluate the long-term safety, tolerability, and efficacy of atumelnant (CRN04894).

Study Overview

Detailed Description

This single-arm, long-term, open-label, study is designed to evaluate the safety, tolerability, and efficacy of atumelnant (CRN04894) in participants with congenital adrenal hyperplasia (CAH). Enrollment will be limited to individuals who completed a parent Crinetics atumelnant CAH study, and in the opinion of the Investigator had an acceptable benefit-risk assessment in the completed study and would benefit from continued dosing in this Open-Label Extension (OLE) study.

A total of approximately 150 - 200 participants may be enrolled in the study.

Study Type

Interventional

Enrollment (Estimated)

200

Phase

  • Phase 2

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Locations

    • Córdoba Province
      • Córdoba, Córdoba Province, Argentina, 5000
        • Recruiting
        • Crinetics Study Site
      • Rio de Janeiro, Brazil, 20231-092
        • Recruiting
        • Crinetics Study Site
      • São Paulo, Brazil, 05403-000
        • Recruiting
        • Crinetics Study Site
    • Paraná
      • Curitiba, Paraná, Brazil, 80030-110
        • Recruiting
        • Crinetics Study Site
    • Rio Grande do Sul
      • Porto Alegre, Rio Grande do Sul, Brazil, 90410-000
        • Recruiting
        • Crinetics Study Site
    • São Paulo
      • Botucatu, São Paulo, Brazil, 18618-686
        • Recruiting
        • Crinetics Study Site
    • Bavaria
      • Munich, Bavaria, Germany, 80336
        • Recruiting
        • Crinetics Study Site
      • Roma, Italy, 00161
        • Recruiting
        • Crinetics Study Site
      • Birmingham, United Kingdom, CV22DX
        • Recruiting
        • Crinetics Study Site
      • London, United Kingdom, NW1 2BU
        • Recruiting
        • Crinetics Study Site
    • Minnesota
      • Minneapolis, Minnesota, United States, 55455
        • Active, not recruiting
        • Crinetics Study Site, Minneapolis, Minnesota 55454
    • North Carolina
      • Morehead City, North Carolina, United States, 28557
        • Active, not recruiting
        • Crinetics Study Site
    • Pennsylvania
      • Philadelphia, Pennsylvania, United States, 19104
        • Active, not recruiting
        • Crinetics Study Site

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Child
  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

Participants are eligible to be included in the study only if all the following criteria apply:

  1. Participants with CAH who have completed the Treatment Period in a Crinetics parent atumelnant CAH study, and in the opinion of the Investigator had an acceptable benefit-risk assessment in the completed study and would benefit from continued dosing in this extension study.

    1. Group 1: Participants meeting the above criteria and did not have study drug administration interrupted between End of Trial (EOT) of the parent study and the commencement of the OLE study.
    2. Group 2: Participants meeting the above criteria but had study drug administration interrupted between EOT of the parent study and the commencement of the OLE study.
  2. Female participants who engage in heterosexual intercourse must:

    1. Be of nonchildbearing potential, defined as either surgically sterile (ie, hysterectomy, bilateral salpingectomy for at least 3 months, or bilateral oophorectomy), OR
    2. Be postmenopausal with at least 1 year of amenorrhea. In participants with less than 1 year of amenorrhea, confirmation is required with 2 follicle-stimulating hormone (FSH) measurements. A documented, historical test result measured prior to Screening may be used as 1 of the 2 measurements. The FSH value should be ≥30 IU/L to confirm menopausal status, OR
    3. Agree to use a highly effective method of contraception from the beginning of Screening until at least 2 weeks after the last dose of study drug. Contraceptive use by men and women also should be consistent with local regulations regarding the methods of contraception for those participating in clinical studies. Periodic abstinence (ie, calendar, ovulation, symptothermal, postovulation methods) and withdrawal are not acceptable methods of contraception.
  3. Male participants agree to use a condom when sexually active with a female partner of childbearing potential from Screening until at least 2 weeks after the last dose of study drug (or be surgically sterile [ie, vasectomy with a confirmed absence of sperm in ejaculate]; or agree to remain abstinent on a long-term and persistent basis). Male participants should also agree to not donate sperm for the duration of the study and until at least 2 weeks after the last dose of study drug.
  4. Participants are willing and able to give signed informed consent, including compliance with the requirements and restrictions listed in the Informed Consent Form (ICF).
  5. Participants are willing and able to comply with the study procedures as specified in the protocol and comply with the study treatment.

Exclusion Criteria:

Participants are excluded from the study if any of the following criteria apply:

  1. Any medical condition(s) or laboratory findings that, in the opinion of the Investigator, might jeopardize the participant's safety or ability to complete the study.
  2. Participants have known history of (that is within the past 12 months), or current alcohol or drug abuse.
  3. Participants have any mental condition rendering him/her unable to understand the nature, scope, and possible consequences of the study, and/or evidence of poor compliance with medical instructions.
  4. Participants have a known allergy or hypersensitivity to any of the test materials or related compounds, including being at high risk of adrenal insufficiency as judged by the Investigator.
  5. Women who are pregnant or lactating or, if of childbearing potential, who are unwilling to use highly effective contraception as described in this study. Male participants who are unwilling to use highly effective contraception as described in this study.
  6. Participant is an employee or immediate family member of an employee of Crinetics.
  7. Participants who have been dosed with an investigational drug (other than atumelnant) in any prior clinical study within 60 days or 5 half-lives (whichever is longer) prior to informed consent or plan to use an investigational drug in another study.
  8. Participants who have had an active malignant disease within the last 5 years prior to Screening excluding dermal squamous or basal cell carcinoma of the skin with complete local excision or resected cervical carcinoma in situ.
  9. Participants who are committed to an institution by virtue of an order issued either by the judicial or the administrative authorities.

    Specific for Participants Not Currently Receiving Atumelnant

  10. Participants with any clinically significant abnormal laboratory test during Screening or clinically significant concomitant disease other than CAH including but not limited to cardiovascular disease; moderate or severe renal insufficiency (estimated glomerular filtration rate <30 mL/min/1.73 m2 using Chronic Kidney Epidemiology Collaboration [CKD-EPI] formula) at Screening; or Significant liver disease or alanine aminotransferase (ALT) and/or aspartate aminotransferase (AST) >3× upper limit of normal (ULN), and/or total bilirubin >1.5×ULN during Screening. Participants with previously diagnosed Gilbert's syndrome not accompanied by other hepatobiliary disorders and associated with total bilirubin <3.5 mg/dL (<51.3 μmol/L) will be permitted.
  11. Participants with a history of bilateral adrenalectomy, hypopituitarism, or other condition requiring chronic glucocorticoid therapy.
  12. Participants with a history of major surgery/surgical therapy for any cause within 4 weeks prior to Screening.
  13. Participants with poorly controlled diabetes mellitus defined as having a hemoglobin A1c (HbA1c) ≥8.5% (≥69 mmol/mL).
  14. Participants with hypothyroidism who are not receiving adequate hormone replacement therapy based on thyroid hormone levels measured at the time of Screening, as determined by the Investigator.
  15. Participant has an average (of 3 electrocardiograms [ECGs]) Fridericia's corrected QT (QTcF) interval >450 milliseconds (msec) (men) or >470 msec (women), time interval between P and R waves (PR interval) >220 msec, time interval of the QRS complex (QRS) interval >120 msec, second- or third-degree atrioventricular block, left bundle branch block, or hemiblock at Screening.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: N/A
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Treatment
Open-label treatment period (up to 2 years). The maximum atumelnant dose permitted is not to exceed the highest atumelnant dose explored in a parent study for the indication.
Atumelnant is an orally active nonpeptide melanocortin 2 receptor (MC2R) or adrenocorticotropic hormone (ACTH) receptor antagonist.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
Incidence of glucocorticoid (GC) deficiency / adrenal insufficiency and adrenal crisis
Time Frame: Week 108
Week 108
Incidence of hospitalizations related to congenital adrenal hyperplasia (CAH)
Time Frame: Week 108
Week 108
Change from baseline in morning (before 11:00 AM) serum androstenedione (A4) over time
Time Frame: Week 108
Week 108
Incidence of treatment-emergent adverse events (TEAEs), including treatment-emergent serious adverse events (SAEs), adverse events of special interest (AESI [adrenal insufficiency]) and any adverse events (AEs) leading to discontinuation
Time Frame: Week 108
Week 108

Secondary Outcome Measures

Outcome Measure
Time Frame
Change from baseline in morning (before 11:00 AM) serum 17-hydroxyprogesterone (17-OHP) over time
Time Frame: Week 108
Week 108
Change from baseline in daily glucocorticoid (GC) dose (hydrocortisone [HC] mg equivalents body surface area [BSA] adjusted) over time
Time Frame: Week 108
Week 108

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

February 25, 2025

Primary Completion (Estimated)

July 1, 2029

Study Completion (Estimated)

August 1, 2029

Study Registration Dates

First Submitted

November 27, 2024

First Submitted That Met QC Criteria

November 27, 2024

First Posted (Actual)

December 2, 2024

Study Record Updates

Last Update Posted (Actual)

June 29, 2026

Last Update Submitted That Met QC Criteria

June 24, 2026

Last Verified

June 1, 2025

More Information

Terms related to this study

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

Yes

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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