DURACLON Drug Patent Profile

Which patents cover Duraclon, and when can generic versions of Duraclon launch?

Duraclon is a drug marketed by Mylan Institutional and is included in one NDA.

The generic ingredient in DURACLON is clonidine hydrochloride. There are twenty-two drug master file entries for this compound. Forty-three suppliers are listed for this compound. Additional details are available on the clonidine hydrochloride profile page.

DrugPatentWatch^® Litigation and Generic Entry Outlook for Duraclon

A generic version of DURACLON was approved as clonidine hydrochloride by ACTAVIS ELIZABETH on December 16^th, 1986.

Summary for DURACLON

US Patents:	0
Applicants:	1
NDAs:	1
Finished Product Suppliers / Packagers:	1
Raw Ingredient (Bulk) Api Vendors:	1
Clinical Trials:	9
Patent Applications:	2,936
Drug Prices:	Drug price information for DURACLON
What excipients (inactive ingredients) are in DURACLON?	DURACLON excipients list
DailyMed Link:	DURACLON at DailyMed

See drug prices for DURACLON

Recent Clinical Trials for DURACLON

Identify potential brand extensions & 505(b)(2) entrants

Sponsor	Phase
Kootenai Health	Phase 4
University of Louisville	Phase 4
Arthroplasty Foundation, Inc.	Phase 4

See all DURACLON clinical trials

Pharmacology for DURACLON

Drug Class	Central alpha-2 Adrenergic Agonist
Mechanism of Action	Adrenergic alpha2-Agonists

US Patents and Regulatory Information for DURACLON

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Mylan Institutional	DURACLON	clonidine hydrochloride	INJECTABLE;INJECTION	020615-001	Oct 2, 1996	AP	RX	Yes	No
Mylan Institutional	DURACLON	clonidine hydrochloride	INJECTABLE;INJECTION	020615-002	Apr 27, 1999		DISCN	Yes	No

DURACLON Market Dynamics, Patent Status, FDA Exclusivity, and Financial Trajectory

Last updated: August 1, 2026

Duraclon is a legacy injectable formulation of clonidine hydrochloride used as an epidural adjunct to opioid therapy for severe cancer pain. Its commercial profile is defined by narrow clinical use, generic active-ingredient availability, limited public revenue disclosure, and an effectively expired patent and regulatory exclusivity position. Duraclon is unlikely to generate material standalone revenue for its sponsor, although it can retain value as a hospital injectable with established labeling and manufacturing infrastructure.

What is Duraclon and how is it used?

Duraclon is clonidine hydrochloride injection, supplied at a concentration of 0.1 mg/mL for epidural administration. The FDA-approved indication is adjunctive treatment with opioid analgesics for the treatment of severe cancer pain that is not adequately controlled by opioids alone. It is administered through a continuous epidural infusion rather than as a conventional oral antihypertensive product (U.S. Food and Drug Administration [FDA], n.d.-a).

Attribute	Duraclon profile
Brand name	Duraclon
Active ingredient	Clonidine hydrochloride
Dosage form	Injectable solution
Concentration	0.1 mg/mL
Route	Epidural
Therapeutic use	Adjunct to opioid therapy for severe cancer pain
Regulatory category	Prescription drug
NDA	019896
Product type	Small-molecule drug
Biologic status	Not a biologic
Biosimilar pathway	Not applicable
Primary commercial channel	Hospitals, specialty distributors, institutional pharmacies

Clonidine is an alpha-2 adrenergic agonist. In the epidural setting, it can enhance analgesia and reduce the opioid dose required for some patients. The product’s clinical use is constrained by hypotension, bradycardia, sedation, and the need for monitoring.

What is the FDA regulatory status of Duraclon?

Duraclon has an approved FDA labeling framework for epidural use. Its clinical positioning differs from oral clonidine products, which are primarily used for hypertension and other off-label indications. The approved Duraclon label establishes a specialized use case rather than a broad outpatient market (FDA, n.d.-a).

The product is subject to the conventional prescription-drug framework. It is not an orphan biologic, vaccine, gene therapy, or complex injectable requiring a biosimilar approval pathway. A competing clonidine injection would generally be evaluated through an abbreviated or conventional small-molecule route, depending on the product’s regulatory strategy and reference-product status.

FDA-related commercial considerations include:

• The product has an established approved route and indication.
• The approved label may provide a marketing advantage over compounded or unapproved alternatives.
• Institutional buyers may prefer an FDA-approved product for formulary, procurement, and risk-management reasons.
• The label does not create perpetual protection against generic or alternative clonidine products.
• Safety monitoring requirements limit use outside controlled clinical settings.

When does Duraclon lose exclusivity?

Duraclon’s original regulatory and patent exclusivity expired many years ago. The product was approved in the 1980s, placing it well beyond the standard five-year new chemical entity exclusivity period and the 20-year patent term applicable to modern small-molecule patents.

Exclusivity category	Duraclon status
New chemical entity exclusivity	Expired
Orphan-drug exclusivity	Not applicable
Pediatric exclusivity	No current protection
Patent term for original clonidine technology	Expired
Regulatory exclusivity	Expired
Current market protection	Brand recognition, approved labeling, supply reliability, and institutional presence

The active ingredient, clonidine hydrochloride, is a mature generic compound. Any original compound or early formulation patents would have expired. Later patents could theoretically have covered specific concentrations, containers, delivery systems, or manufacturing methods, but those rights would need to remain unexpired and enforceable to create current commercial protection.

What patents protect Duraclon?

Duraclon does not have a meaningful current patent moat around clonidine hydrochloride itself. The commercial value of the product is therefore based on regulatory status and supply execution rather than composition-of-matter protection.

Patent estate and Orange Book position

The FDA Orange Book is the relevant source for patents and exclusivity associated with approved prescription drug products. A product’s Orange Book listing can include patents covering the active ingredient, formulation, method of use, or other approved-product characteristics (FDA, n.d.-b).

For Duraclon, the commercially relevant patent conclusions are:

1. The clonidine active ingredient is long off patent.
2. Original Duraclon exclusivity has expired.
3. No current composition-of-matter protection should be expected.
4. Any remaining listing would need to relate to a specific formulation, delivery system, or method of use.
5. A generic competitor would focus on approval, pharmaceutical equivalence, manufacturing quality, and market access rather than overcoming a strong blocking patent.

The absence of a meaningful active patent barrier does not eliminate commercial barriers. Injectable products require validated sterile manufacturing, container-closure controls, stability data, quality systems, and reliable hospital distribution.

Are there Paragraph IV challenges to Duraclon?

Paragraph IV litigation is not a central current risk for Duraclon because the product’s commercial protection is largely exhausted and the market is small. A generic applicant would challenge any listed patent by certifying that the patent is invalid, unenforceable, or would not be infringed. The practical incentive to litigate depends on expected sales, not merely the existence of a listed patent.

Litigation factor	Commercial assessment
Patent blocking risk	Low
Paragraph IV incentive	Low to moderate, depending on market size
Expected litigation value	Limited by narrow epidural indication
Main approval hurdle	Sterile injectable development and manufacturing
Main market hurdle	Hospital contracting and low-volume demand

The more probable competitive pathway is a nonlitigated generic launch or a limited institutional product introduction after regulatory approval. A patent settlement would have little commercial relevance unless a later formulation or device patent created a genuine barrier.

What formulations are protected by Duraclon?

The product’s formulation is commercially important even though it is not strongly protected by active patents. Duraclon is an injectable clonidine hydrochloride solution intended for epidural administration. The formulation must meet sterile injectable standards and must be suitable for controlled neuraxial use.

Relevant formulation and manufacturing attributes include:

• Sterility and particulate control.
• Accurate low-dose concentration.
• Compatibility with epidural infusion systems.
• Container-closure integrity.
• Stability during storage and administration.
• Control of preservatives and excipients appropriate for the intended route.
• Batch-to-batch concentration consistency.

These requirements can create practical barriers for competitors. They do not generally provide the same duration or strength as a valid composition patent. A manufacturer that can produce a safe, stable, approved sterile injectable may compete even without replicating every commercial characteristic of the branded product.

How strong is the Duraclon patent estate?

Duraclon has a weak current patent estate and a moderate practical manufacturing barrier.

Protection category	Strength
Active ingredient patent	None expected to remain
Original product exclusivity	Expired
Method-of-use protection	Weak or expired
Formulation patents	No material current barrier publicly established
Device or delivery-system patents	Not central to the product
Sterile manufacturing barrier	Moderate
Regulatory-label advantage	Moderate
Brand and institutional familiarity	Low to moderate
Overall patent strength	Low

The product’s commercial defensibility is operational rather than legal. A reliable supplier with FDA-compliant injectable capacity can retain share even in a nominally generic market.

What is Duraclon’s financial trajectory?

No standalone Duraclon revenue is publicly disclosed by its commercial sponsor. The product is typically included within broader injectable, hospital, or specialty pharmaceutical revenue categories. Public company filings generally report segment or portfolio-level sales rather than sales for individual mature injectable products.

Its likely financial trajectory has four stages:

Launch and protected commercialization

Duraclon benefited from the usual economics of an approved branded product during the period before generic clonidine availability and before expiration of the relevant patent and regulatory rights. The market was limited by the product’s specialized epidural indication.

Post-exclusivity erosion

After patent and regulatory exclusivity expired, price competition reduced the product’s ability to command a branded premium. The decline would have been amplified by the availability of clonidine in other dosage forms and by hospital purchasing pressure.

Mature hospital product phase

Duraclon’s current economics are likely driven by recurring but limited institutional demand. A mature injectable can remain commercially useful when it has:

• An established FDA-approved label.
• A known National Drug Code and purchasing history.
• Stable hospital formulary placement.
• Reliable sterile supply.
• Limited direct competition for the precise dosage form.

Long-term portfolio rationalization

The principal financial risk is not sudden patent loss. It is portfolio rationalization. A low-volume injectable can become unattractive if manufacturing costs, quality requirements, shortages, or procurement discounts compress margins. The product may remain available if it supports a broader hospital portfolio, even when standalone revenue is modest.

Which companies compete with Duraclon?

Competition exists at several levels rather than through one direct branded rival.

Direct product competition

The closest competitors are generic clonidine hydrochloride injection products with equivalent or similar concentration and route. Availability may vary by supplier, market, and institutional contract.

Therapeutic competition

Physicians may use alternative neuraxial analgesic strategies, including opioid-only epidural therapy, local anesthetic combinations, other alpha-2 agonists, or patient-controlled analgesia. These alternatives compete for the same clinical decision even when they are not pharmaceutical equivalents.

Compounded products

Compounding pharmacies can supply clonidine preparations for institutional use. Compounded products may compete on price or customization but do not necessarily provide the same FDA-approved labeling and manufacturing framework as Duraclon.

Competitor type	Effect on Duraclon
Generic clonidine injection	Direct price pressure
Compounded clonidine	Customization and cost competition
Alternative neuraxial adjuncts	Clinical substitution
Opioid-only therapy	Reduces need for adjunctive clonidine
Other hospital injectables	Compete for formulary and procurement budget

What generic entry risks exist for Duraclon?

Generic entry risk is structurally high because the active ingredient is old, the exclusivity period has ended, and the product is a small molecule. Commercial entry may still be limited by the size of the market.

The most likely generic launch scenarios are:

1. A direct-equivalent clonidine injection enters through an abbreviated regulatory pathway.
2. A hospital-focused manufacturer offers the product as part of a broader injectable portfolio.
3. A shortage or supply disruption creates temporary price strength for remaining suppliers.
4. A compounded alternative gains share in institutions willing to accept different procurement and regulatory characteristics.
5. Low demand limits the number of approved suppliers despite the absence of strong patents.

The principal market risk is gradual price erosion rather than a single disruptive launch. The product can also experience intermittent supply pressure because sterile injectable manufacturing has a concentrated supplier base.

What patent litigation or settlement agreements affect Duraclon?

Duraclon is not associated with a commercially significant current patent-litigation narrative in the public record cited here. There is no evident high-value patent settlement framework comparable to those surrounding major oncology, immunology, or cardiovascular blockbusters.

Any future dispute would more likely concern:

• Product quality or manufacturing compliance.
• Distribution or supply contracts.
• Trademark or trade-name issues.
• A later formulation or delivery system.
• Regulatory equivalence between competing injectable products.

The absence of a major settlement is consistent with Duraclon’s low-value, post-exclusivity market position.

How does Duraclon compare with oral clonidine and other neuraxial products?

Product category	Main use	Market size	Patent position	Duraclon relationship
Duraclon epidural injection	Adjunct for severe cancer pain	Narrow	Expired	Reference product
Oral clonidine	Hypertension and other uses	Broader	Expired	Same active ingredient, different route
Generic clonidine injection	Institutional neuraxial use	Narrow	Generally unprotected	Direct competitor
Epidural opioids	Cancer and postoperative pain	Moderate	Mostly mature	Therapeutic substitute
Alpha-2 agonist alternatives	Neuraxial analgesia and sedation	Variable	Product-specific	Clinical substitute
Compounded neuraxial preparations	Institutional and customized use	Fragmented	Depends on formulation	Price and availability competitor

Oral clonidine’s larger market does not automatically expand Duraclon’s revenue. The route, concentration, labeling, and clinical setting are different. Duraclon remains a specialized hospital product.

What is the geographic commercial outlook for Duraclon?

The United States is the primary market relevant to the FDA-approved Duraclon label. International demand depends on national approvals, hospital practice, local compounding rules, procurement systems, and the availability of generic clonidine injections.

Geographic expansion is constrained by:

• Small addressable patient population.
• Local rules governing epidural medicines.
• Different opioid-prescribing practices.
• National reimbursement and hospital tender systems.
• Sterile injectable registration requirements.
• Availability of local generic suppliers.

The product is more likely to remain a niche institutional medicine than become a major international growth asset.

Key Takeaways

• Duraclon is clonidine hydrochloride injection for epidural use as an adjunct to opioid treatment of severe cancer pain.
• Its patent and regulatory exclusivity have expired.
• The current patent estate is weak, with no meaningful active-ingredient barrier.
• Paragraph IV litigation and patent settlements have limited economic significance.
• Direct competition comes from generic clonidine injections and compounded preparations.
• The product’s strongest defenses are FDA-approved labeling, hospital familiarity, and reliable sterile supply.
• Standalone revenue is not publicly disclosed and is likely modest relative to large pharmaceutical products.
• Financial performance is more sensitive to hospital contracting, manufacturing costs, and supply continuity than to intellectual-property protection.
• The primary long-term risk is portfolio rationalization and price erosion, not a new patent cliff.

Frequently Asked Questions

Is Duraclon the same as oral clonidine?

No. Both contain clonidine, but Duraclon is an injectable product labeled for epidural administration, while oral clonidine products have different dosage forms, routes, labeling, and clinical uses.

Is Duraclon a controlled substance?

Duraclon contains clonidine, which is not an opioid controlled substance. Its use with epidural opioids still requires clinical monitoring because of hypotension, bradycardia, sedation, and analgesic effects.

Can a generic company copy Duraclon without a license?

A company can pursue approval of a competing clonidine injection without licensing expired Duraclon patents. It must satisfy FDA requirements for pharmaceutical quality, sterility, labeling, and regulatory approval.

Does Duraclon qualify for biosimilar competition?

No. Duraclon is a small-molecule clonidine injection, not a biologic. Competing products would use generic-drug regulatory pathways rather than the biosimilar pathway.

Why might Duraclon remain on the market after patent expiration?

An approved hospital injectable can retain demand because of established labeling, formulary history, procurement familiarity, and limited supplier availability. These commercial factors can support continued marketing even without patent protection.

References

1. U.S. Food and Drug Administration. (n.d.-a). Duraclon (clonidine hydrochloride injection) prescribing information. FDA.
2. U.S. Food and Drug Administration. (n.d.-b). Approved drug products with therapeutic equivalence evaluations: Orange Book. FDA.
3. National Library of Medicine. (n.d.). Duraclon: Clonidine hydrochloride injection labeling. DailyMed.
4. Hikma Pharmaceuticals PLC. (2024). Annual report and accounts 2023. Hikma Pharmaceuticals PLC.