Investigational Drug Information for Chronocort

What is the drug development status for Chronocort?

Chronocort is an investigational drug.

There have been 11 clinical trials for Chronocort. The most recent clinical trial was a Phase 3 trial, which was initiated on February 22^nd 2016.

The most common disease conditions in clinical trials are Adrenogenital Syndrome, Adrenal Hyperplasia, Congenital, and Hyperplasia. The leading clinical trial sponsors are Diurnal Limited, Simbec Research, and National Institutes of Health (NIH).

Summary for Chronocort

US Patents	0
International Patents	0
US Patent Applications	4,473
WIPO Patent Applications	2,812
Japanese Patent Applications	613
Clinical Trial Progress	Phase 3 (2016-02-22)
Vendors	50

Recent Clinical Trials for Chronocort

Title	Sponsor	Phase
Long-term Safety Study of Chronocort in the Treatment of Participants With Congenital Adrenal Hyperplasia	Diurnal Limited	Phase 3
Chronocort Versus Plenadren Replacement Therapy in Adults With Adrenal Insufficiency	Diurnal Limited	Phase 2
Comparison of Chronocort Versus Standard Hydrocortisone Replacement Therapy in Participants Aged 16 Years and Over With Congenital Adrenal Hyperplasia	Diurnal Limited	Phase 3

See all Chronocort clinical trials

Clinical Trial Summary for Chronocort

Top disease conditions for Chronocort

Top clinical trial sponsors for Chronocort

See all Chronocort clinical trials

US Patents for Chronocort

Drugname	Patent Number	Patent Title	Patent Assignee	Estimated Expiration

Chronocort Development Update and Market Projection: Efmody, FDA Status, Patents, and Commercial Outlook

Last updated: September 4, 2026

Chronocort is Diurnal Group’s modified-release hydrocortisone candidate for adult congenital adrenal hyperplasia (CAH). It is marketed as Efmody in the European Union and United Kingdom. The product is designed to reproduce the overnight rise in cortisol that conventional immediate-release hydrocortisone does not reliably provide.

Chronocort has completed European development and received marketing authorization in the EU and UK. Diurnal submitted a U.S. New Drug Application (NDA), and the FDA accepted the application for review in 2024. The commercial opportunity is concentrated in a small, specialized population, but the product can command premium pricing if it demonstrates lower androgen burden, improved disease control, and reduced treatment complexity.

What is Chronocort and how does the drug work?

Chronocort is an oral modified-release formulation of hydrocortisone. Its release profile is intended to provide:

• Delayed overnight hydrocortisone delivery.
• A more physiologic early-morning cortisol exposure.
• Suppression of the early-morning adrenocorticotropic hormone, or ACTH, surge.
• Lower adrenal androgen production.
• Twice-daily dosing rather than multiple immediate-release doses.

The product is intended for adults with CAH, an inherited disorder in which impaired cortisol synthesis causes chronic ACTH elevation and excess adrenal androgen production. The principal target population includes patients with 21-hydroxylase deficiency, the most common form of CAH.

Efmody received European authorization in 2021 for replacement therapy in adults with CAH. The product is prescribed under specialist endocrinology supervision. [1]

What is the latest Chronocort development update?

Diurnal completed the main European clinical development program and advanced Chronocort into U.S. regulatory review.

Milestone	Status or date
Phase 2 development	Completed
European pivotal development	Completed
EU authorization under the name Efmody	2021
UK availability	Commercially launched following authorization
U.S. NDA submission	Completed
FDA NDA acceptance	Publicly disclosed in 2024
U.S. indication	Adult CAH, subject to FDA review
U.S. commercial status	Not established until FDA approval and launch

The U.S. program relied on clinical data evaluating the ability of modified-release hydrocortisone to improve overnight cortisol replacement and suppress early-morning ACTH. The primary commercial question is whether the FDA accepts the benefit-risk profile for a defined adult CAH population and whether the product label supports broad use or restricts prescribing to selected patients.

The European authorization provides regulatory validation, but it does not guarantee U.S. approval. The FDA may impose requirements involving manufacturing controls, pharmacokinetic consistency, long-term safety, or the proposed indication.

What is the FDA regulatory status of Chronocort?

The FDA accepted Diurnal’s Chronocort NDA for review in 2024. Acceptance indicates that the application was sufficiently complete for substantive review. It does not indicate that the FDA has approved the product.

Chronocort would enter the U.S. market as a prescription hydrocortisone replacement therapy for CAH if approved. The U.S. regulatory pathway is commercially important because the United States contains one of the largest concentrated markets for rare endocrine disorders and generally supports higher branded-drug pricing than European markets.

Chronocort is not a biologic. Biosimilar competition is therefore not relevant. The principal future threats are:

1. Immediate-release generic hydrocortisone.
2. Other glucocorticoid regimens, including prednisone and dexamethasone.
3. New modified-release or continuous-delivery hydrocortisone products.
4. Pharmacy substitution pressure if payers classify Chronocort as therapeutically interchangeable with conventional hydrocortisone.

When does Chronocort lose exclusivity?

Chronocort’s exclusivity profile has two separate components: regulatory exclusivity and patent protection.

European authorization does not create a single worldwide exclusivity date. Exclusivity depends on the relevant country, formulation patents, pediatric obligations, supplementary protection certificates, and national reimbursement rules.

In the United States, the key dates will depend on:

• The FDA approval date.
• Listed patents in the Orange Book.
• Any granted patent-term extension.
• Orphan-drug exclusivity, if granted.
• Five-year or three-year Hatch-Waxman exclusivity, depending on the legal basis of approval.
• The scope of any patent covering modified-release hydrocortisone, dosing, or manufacturing.

Chronocort had no U.S. Orange Book status before FDA approval because an unapproved NDA product cannot have an effective Orange Book listing. After approval, the product’s patent exposure will depend on patents Diurnal or its licensees list with the FDA.

No reliable commercial forecast should use a single “Chronocort expiry date” without separating formulation, method-of-use, and manufacturing patents.

What patents protect Chronocort?

The commercial protection for Chronocort is expected to center on formulation and release-profile technology rather than the hydrocortisone molecule itself. Hydrocortisone is an old active ingredient and is not protected by meaningful composition-of-matter exclusivity.

Potential protection categories include:

Protection category	Commercial relevance
Modified-release hydrocortisone formulation	Protects the tablet composition and release pattern
Pulsatile or chronotherapeutic delivery	May protect overnight and morning cortisol exposure
Dosing regimen	May cover twice-daily administration or timing relative to sleep
Treatment of CAH	May cover ACTH or androgen control in a defined patient population
Manufacturing process	Can increase the cost and complexity of workarounds
Product-by-process limitations	May create narrower infringement positions

The most defensible protection is likely to be formulation-based if the release profile depends on a particular matrix, coating, polymer system, or manufacturing sequence. Method-of-use patents may be more vulnerable if competitors can reach the same therapeutic outcome with a different dosing schedule.

Patent strength is therefore moderate rather than absolute:

• Active-ingredient protection: weak or expired.
• Formulation protection: potentially meaningful.
• Method-of-use protection: potentially narrow.
• Manufacturing protection: potentially useful but difficult to assess without claim charts.
• Product differentiation: stronger than molecule-level exclusivity because immediate-release hydrocortisone does not reproduce the same pharmacokinetic profile.

What formulations and methods of use are protected?

Chronocort’s value is tied to delivery timing. Conventional hydrocortisone replacement often produces a rapid concentration increase followed by decline. Chronocort is intended to deliver hydrocortisone later during the night and into the early morning.

The principal protected use case is adult CAH in patients who require improved overnight glucocorticoid replacement. Potential clinical claims include:

• Reduction of early-morning ACTH.
• Reduction of 17-hydroxyprogesterone and adrenal androgen excess.
• Improved biochemical control with fewer daily doses.
• More consistent overnight cortisol exposure.
• Reduced need for high total daily glucocorticoid doses.

A competitor could challenge these claims by using another modified-release tablet, a liquid formulation, an infusion pump, or a different dosing schedule. That creates a design-around risk even if Chronocort’s formulation patents remain enforceable.

Which companies are challenging Chronocort?

No major Paragraph IV challenge or material U.S. patent litigation involving Chronocort had been publicly established in the available development record before U.S. commercialization.

The likely challenger group includes:

• Generic hydrocortisone manufacturers.
• Specialty endocrine companies.
• Developers of modified-release glucocorticoid products.
• Firms commercializing continuous subcutaneous hydrocortisone infusion.
• Companies with established CAH products or endocrine sales forces.

A generic immediate-release hydrocortisone company would not automatically reproduce Chronocort’s pharmacokinetic profile. A direct formulation challenge would require demonstrating pharmaceutical equivalence or a legally acceptable alternative, depending on the approved regulatory pathway.

What is the competitive landscape for Chronocort?

Chronocort competes against inexpensive, established therapies rather than a single direct branded rival.

Therapy	Principal advantage	Principal limitation
Immediate-release hydrocortisone	Low cost and broad availability	Nonphysiologic exposure and multiple daily doses
Prednisone or prednisolone	Longer duration and low pill burden	Greater concern over chronic glucocorticoid adverse effects
Dexamethasone	Strong ACTH suppression	Higher risk of overtreatment and long biological duration
Chronocort/Efmody	Modified overnight exposure and twice-daily dosing	Premium price and limited patient population
Continuous hydrocortisone infusion	Highly programmable delivery	Device burden, cost, and invasive administration

Chronocort’s commercial positioning depends on identifying patients whose disease remains poorly controlled despite conventional hydrocortisone. The strongest target segment is likely adults with persistent early-morning androgen excess, fluctuating symptoms, or a high treatment burden.

What is the market size and revenue potential for Chronocort?

CAH is a rare disease. Published prevalence estimates commonly place classic CAH near 1 in 15,000 to 1 in 20,000 live births, although diagnosed prevalence varies by geography and case definition. [2]

A practical U.S. commercial model is:

Scenario	Addressable U.S. adults	Annual net price	Potential annual revenue
Conservative	5,000	$15,000	$75 million
Base case	10,000	$25,000	$250 million
Upside	15,000	$35,000	$525 million

These figures are market scenarios, not reported company guidance. They assume that Chronocort receives an adult CAH label, secures specialist reimbursement, and captures patients inadequately controlled on immediate-release therapy.

European revenue is likely to be lower per patient because of national price negotiation and reimbursement controls. The European market remains commercially relevant because Efmody has established regulatory status and physician experience, but sales scale depends on country-level reimbursement and Diurnal’s commercial infrastructure.

A realistic peak sales range for the global product is approximately $150 million to $400 million annually. Reaching the upper end would require:

• U.S. approval.
• Broad payer coverage.
• A differentiated label.
• Strong endocrinology adoption.
• Low patient discontinuation.
• Limited substitution by compounded or generic modified-release products.

What licensing deals affect Chronocort?

Chronocort was developed by Diurnal Group, which has built the product around its modified-release hydrocortisone platform. The company’s strategy has included direct commercialization in selected markets and potential regional partnerships.

The commercial value of any license depends on whether a partner receives:

• U.S. rights.
• European rights.
• Manufacturing rights.
• Regulatory responsibility.
• Pediatric or lifecycle-development obligations.
• Rights to future hydrocortisone products.

No licensing structure should be assumed to transfer worldwide rights without confirmation from company filings or transaction announcements. Regional licensing is more likely than a single global transaction because Efmody requires specialized endocrinology promotion and country-specific reimbursement work.

What patent litigation and settlement risks exist?

The principal litigation risks are likely to emerge after U.S. approval, when Diurnal or a commercial partner lists patents in the Orange Book and generic companies evaluate Paragraph IV filings.

Potential disputes could involve:

• Whether a generic product has the same modified-release profile.
• Whether a patent claim requires a particular polymer or coating.
• Whether a dosing method is infringed by a different schedule.
• Whether the formulation claims are obvious in view of prior hydrocortisone products.
• Whether a generic applicant has an acceptable design-around.

A settlement could delay generic entry beyond the earliest patent expiry, but no public settlement should be assumed without a filed agreement or court record. The most likely early challenge would target formulation obviousness or claim breadth rather than the hydrocortisone molecule.

How strong is the Chronocort patent estate?

Chronocort has a differentiated product profile but not a conventional new-molecule patent position.

Factor	Assessment
Molecule exclusivity	Low
Formulation differentiation	Moderate to high
Method-of-use protection	Moderate, potentially narrow
Manufacturing barriers	Moderate
Clinical switching barriers	Moderate
Generic substitution risk	Moderate after regulatory approval
Biosimilar risk	Not applicable
Overall commercial protection	Moderate

The product’s strongest defense is the combination of formulation know-how, clinical evidence, physician familiarity, and patient-specific disease control. Patent protection alone is unlikely to prevent all competition indefinitely.

What are the main generic launch scenarios?

Early generic substitution

A generic company launches an alternative hydrocortisone product after the relevant patents expire or are successfully challenged. Price erosion could be substantial because immediate-release hydrocortisone is inexpensive.

Delayed direct competition

Generic companies avoid direct formulation competition but continue selling immediate-release hydrocortisone. Chronocort retains a premium niche among patients requiring improved circadian control.

Formulation-based challenge

A competitor develops a different delayed-release hydrocortisone tablet. This presents the greatest long-term threat because it could preserve the therapeutic concept while avoiding Chronocort-specific claims.

Specialist-market defense

Diurnal maintains share through endocrine-specialist prescribing, real-world evidence, and reimbursement restrictions. This scenario supports durable niche revenue but limits peak penetration.

Key Takeaways

• Chronocort is a modified-release hydrocortisone product for adult CAH and is marketed in Europe as Efmody.
• European authorization was obtained in 2021.
• Diurnal advanced a U.S. NDA into FDA review in 2024.
• The product’s value comes from overnight hydrocortisone delivery and early-morning ACTH control.
• Hydrocortisone itself has no meaningful new-molecule exclusivity.
• Formulation, dosing, method-of-use, and manufacturing patents are the relevant protection categories.
• Biosimilar risk does not apply because Chronocort is a small-molecule drug.
• U.S. commercial potential is likely to be concentrated in a specialty population of several thousand to roughly 15,000 adult patients.
• A reasonable global peak-sales range is approximately $150 million to $400 million, subject to FDA approval, pricing, reimbursement, and adoption.
• Generic and alternative modified-release products pose the principal long-term competitive risk.
• No material Paragraph IV litigation or settlement should be treated as established without a public court or regulatory record.

FAQs About Chronocort

Is Chronocort the same drug as Efmody?

Yes. Efmody is the European and UK commercial name for Diurnal’s modified-release hydrocortisone product known as Chronocort in development and U.S. regulatory materials.

Is Chronocort approved in the United States?

The FDA accepted Diurnal’s NDA for review in 2024. FDA acceptance is not the same as approval. U.S. launch requires final FDA approval and commercial readiness.

Can generic hydrocortisone replace Chronocort?

Immediate-release generic hydrocortisone can replace conventional hydrocortisone therapy but does not necessarily reproduce Chronocort’s delayed overnight release profile.

Does Chronocort have orphan-drug exclusivity?

The availability and duration of U.S. orphan-drug exclusivity depend on FDA designation and approval records. Orphan status should be verified separately from patent protection.

What is the main investment risk for Chronocort?

The main risks are a restricted U.S. label, reimbursement resistance to premium pricing, limited patient identification, formulation patent challenges, and competition from alternative modified-release or continuous-delivery hydrocortisone products.

References

1. European Medicines Agency. (2021). Efmody: EPAR - product information. European Union.
2. Speiser, P. W., Arlt, W., Auchus, R. J., Baskin, L. S., Conway, G. S., Merke, D. P., Meyer-Bahlburg, H. F. L., Miller, W. L., Murad, M. H., Oberfield, S. E., Ritzen, M., & White, P. C. (2018). Congenital adrenal hyperplasia due to steroid 21-hydroxylase deficiency: An Endocrine Society clinical practice guideline. The Journal of Clinical Endocrinology & Metabolism, 103(11), 4043-4088.
3. Diurnal Group plc. (2024). Corporate announcements and regulatory updates concerning Chronocort and Efmody. Diurnal Group plc.
4. U.S. Food and Drug Administration. (2024). Orange Book: Approved drug products with therapeutic equivalence evaluations. U.S. Department of Health and Human Services.
5. U.S. Food and Drug Administration. (2024). Drugs@FDA and NDA application review resources. U.S. Department of Health and Human Services.