Methyprylon - Generic Drug Details

What are the generic drug sources for methyprylon and what is the scope of freedom to operate?

Methyprylon is the generic ingredient in one branded drug marketed by Roche and is included in one NDA. Additional information is available in the individual branded drug profile pages.

Summary for methyprylon

US Patents:	0
Tradenames:	1
Applicants:	1
NDAs:	1
Raw Ingredient (Bulk) Api Vendors:	15
DailyMed Link:	methyprylon at DailyMed

Anatomical Therapeutic Chemical (ATC) Classes for methyprylon

N05CE	Piperidinedione derivatives
N05C	HYPNOTICS AND SEDATIVES
N05	PSYCHOLEPTICS
N	Nervous system

US Patents and Regulatory Information for methyprylon

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Roche	NOLUDAR	methyprylon	ELIXIR;ORAL	009660-007	Approved Prior to Jan 1, 1982		DISCN	No	No
Roche	NOLUDAR	methyprylon	TABLET;ORAL	009660-004	Approved Prior to Jan 1, 1982		DISCN	No	No
Roche	NOLUDAR	methyprylon	TABLET;ORAL	009660-002	Approved Prior to Jan 1, 1982		DISCN	No	No

Methyprylon Market Dynamics, Patent Status, and Financial Trajectory

Last updated: September 9, 2026

Methyprylon is an obsolete sedative-hypnotic with no meaningful current pharmaceutical market, no active U.S. commercial franchise, and no identifiable current Orange Book protection. Historically marketed under the brand name Noludar, the drug lost commercial relevance as benzodiazepines and newer hypnotics replaced older sedatives. Its financial trajectory is therefore a decline from mid-20th-century prescription use to market withdrawal, with no material present-day revenue opportunity in regulated markets.

What is methyprylon and how was it used?

Methyprylon, also known as methylpyrilone, is a synthetic sedative-hypnotic in the piperidinedione class. It was developed for the short-term treatment of insomnia and related sleep complaints. The drug was marketed principally as Noludar in the United States and other markets.

Attribute	Methyprylon
Active ingredient	Methyprylon, also called methylpyrilone
Chemical class	Piperidinedione sedative-hypnotic
Historical brand	Noludar
Primary use	Insomnia and short-term sedation
Administration	Oral
Development period	Mid-20th century
Current U.S. status	No active commercial product identified
Current Orange Book position	No marketed reference product identified
Current patent value	No apparent commercial exclusivity
Competitive substitutes	Benzodiazepines, nonbenzodiazepine hypnotics, sedating antidepressants, antihistamines

Methyprylon was part of an earlier generation of hypnotics that included barbiturates and other central nervous system depressants. Its clinical utility was limited by sedation, tolerance, dependence potential, impairment, and toxicity in overdose. These liabilities became more commercially important as physicians gained access to drugs with broader therapeutic margins.

When did methyprylon lose exclusivity and commercial relevance?

Methyprylon’s patent and commercial history dates to the mid-20th century, when pharmaceutical protection periods were shorter than under the modern U.S. patent system. Any original compound or product patents would have expired decades ago. No active U.S. composition-of-matter, formulation, or method-of-use patent appears to preserve exclusivity for methyprylon today.

The commercial decline occurred in stages:

Period	Market development
1950s	Introduction of methyprylon as a prescription sedative-hypnotic
1960s	Use continued while benzodiazepines entered the market
1970s	Prescribing shifted toward newer hypnotics and anxiolytics
Late 1970s to 1980s	Product availability declined and the U.S. commercial franchise ended
1990s onward	Methyprylon became an obsolete or discontinued medicine in major regulated markets
Present	No established branded or generic market in the United States

The exact commercial withdrawal date can vary by country and by whether the reference is to marketing discontinuation, regulatory discontinuation, or removal of a specific product presentation. The available regulatory record supports the conclusion that methyprylon is no longer an active U.S. pharmaceutical product rather than a product with ongoing patent-based exclusivity.

What is the FDA regulatory status of methyprylon?

Methyprylon is not an actively marketed FDA-approved medicine in the current U.S. prescription market. It does not have a contemporary reference product with an active commercial approval comparable to currently marketed hypnotics.

The FDA Orange Book identifies approved drug products and patent or exclusivity information for products with current regulatory relevance. Methyprylon does not appear to have an active marketed reference-listed drug that supports a current abbreviated new drug application pathway. The practical regulatory position is therefore:

1. No current U.S. branded methyprylon product.
2. No active Orange Book patent listing supporting delayed generic entry.
3. No current commercial abbreviated application market.
4. Any new sponsor would face a redevelopment and regulatory strategy rather than a conventional generic launch.

Historical approval status should not be confused with current market authorization. A compound can have been marketed historically while having no present-day approved product, active label, or commercial manufacturer.

What patents protect methyprylon today?

No commercially meaningful active patent estate protects methyprylon in the United States or other major markets. The relevant exclusivity categories are summarized below.

Protection category	Current commercial position
Original compound patent	Expired decades ago
Salt or polymorph patent	No material active protection identified
Formulation patent	No active marketed formulation estate identified
Method-of-use patent	No current patent-based market protection identified
Manufacturing patent	Any historic protection would be expired or commercially irrelevant
Pediatric exclusivity	None identified
Orphan-drug exclusivity	None identified
Regulatory exclusivity	None identified

A modern sponsor could theoretically pursue a patent on a new formulation, delivery system, combination, or narrow medical use. Such a patent would protect only the newly claimed invention. It would not restore exclusivity to the old methyprylon molecule itself, and patentability would depend on novelty, non-obviousness, written description, enablement, and credible clinical utility.

Are there Paragraph IV challenges or generic-entry disputes?

No active Paragraph IV litigation or current generic-entry dispute is associated with methyprylon in the U.S. market. The reason is commercial rather than procedural: there is no active reference product generating a conventional Abbreviated New Drug Application market.

Paragraph IV litigation normally arises when a generic applicant challenges an Orange Book-listed patent. Methyprylon lacks the current reference-product and patent-listing structure that would make such litigation economically rational. A historical patent challenge could have occurred during the product’s commercial life, but no active dispute is relevant to present market access.

The likely regulatory pathway for a new methyprylon product would be a full 505(b)(1) or 505(b)(2) application, depending on the sponsor’s proposed formulation, clinical evidence, and ability to rely on existing information. A standard ANDA pathway would require a suitable currently approved reference product and applicable regulatory infrastructure.

What formulations of methyprylon were historically protected?

Methyprylon was principally used in oral dosage forms. The commercially relevant product was an oral hypnotic formulation rather than an advanced delivery system.

No current formulation patent estate appears to protect:

• Immediate-release tablets or capsules.
• Modified-release methyprylon.
• Transdermal delivery.
• Injectable delivery.
• Abuse-deterrent formulations.
• Fixed-dose combinations.
• Modern digital or controlled-release delivery systems.

The technical barrier to reintroducing methyprylon would not be the absence of a dosage form. It would be the clinical and commercial burden of demonstrating that the drug offers a favorable benefit-risk profile compared with safer and more widely accepted alternatives.

How strong is the methyprylon patent estate?

The patent estate is commercially weak to nonexistent.

Exclusivity strength

Methyprylon has no apparent remaining molecule-level exclusivity. The compound entered the market long enough ago that original patent rights would have expired. Any surviving patent family would need to cover a genuinely new formulation, manufacturing process, or use and would need to support a commercially valuable product.

Regulatory strength

Regulatory strength is also limited. A new sponsor would not inherit the market advantages of an active reference-listed drug, a current brand, or a recognized treatment guideline position. The sponsor would need to establish a new regulatory and clinical case.

Litigation strength

Litigation risk from legacy patents is low. The more important risks would involve:

• Clinical safety findings.
• Controlled-substance or abuse-liability classification.
• Product-liability exposure.
• Labeling restrictions.
• Difficulty obtaining physician adoption.
• Competition from generic and branded alternatives.

Which companies marketed or competed with methyprylon?

The most closely associated historical brand was Noludar. Public drug references identify methyprylon as a discontinued medicine rather than a product with a current multinational sponsor.

Its historical competitive set included:

• Barbiturate hypnotics such as secobarbital and pentobarbital.
• Other nonbarbiturate sedatives.
• Benzodiazepines such as diazepam and temazepam.
• Later nonbenzodiazepine hypnotics such as zolpidem.
• Sedating antihistamines and antidepressants used off label or for related sleep complaints.

The competitive shift toward benzodiazepines was commercially decisive. These products offered broad physician familiarity, multiple indications, large sales forces, and stronger lifecycle-management opportunities. Later, nonbenzodiazepine hypnotics created another competitive barrier by offering more modern regulatory positioning and consumer recognition.

What was methyprylon’s historical revenue trajectory?

Reliable product-level revenue figures for methyprylon are not widely available in public company filings or contemporary market databases. The drug was commercialized before the period when pharmaceutical companies routinely disclosed product-level sales in the manner used today.

The financial trajectory can nevertheless be assessed directionally:

Financial phase	Revenue profile	Primary driver
Launch and early adoption	Growth from a prescription sedative base	Novelty and limited alternatives
Mature market	Stable or declining sales	Competition from benzodiazepines
Late commercial period	Accelerated decline	Safety concerns, substitution, and changing prescribing standards
Post-withdrawal	No material regulated-market revenue	Product discontinuation
Current period	Effectively zero branded pharmaceutical revenue	Absence of marketed product

Methyprylon does not appear to represent a material revenue exposure for a current publicly traded pharmaceutical company. It has no meaningful contribution to contemporary pharmaceutical portfolios, licensing transactions, or strategic pipeline valuations.

What financial barriers would affect a methyprylon relaunch?

A relaunch would face a poor risk-adjusted commercial profile.

Clinical development cost

Historical availability of safety data would not eliminate the need for modern evidence. Regulators and physicians would require a current assessment of:

• Abuse and dependence potential.
• Respiratory depression.
• Cognitive and psychomotor impairment.
• Drug interactions.
• Overdose toxicity.
• Effects in older adults.
• Comparative efficacy against approved hypnotics.

Commercial positioning

Methyprylon would enter a crowded market dominated by inexpensive generic products. A sponsor could not rely on molecule-level differentiation unless it developed a new formulation or identified a narrowly defined clinical use.

Reimbursement

A legacy sedative with no established treatment advantage would likely face generic pricing pressure. Payers would have little reason to grant premium reimbursement without evidence of superior safety, adherence, sleep outcomes, or another measurable benefit.

Liability exposure

The historical safety profile would create product-liability concerns. Reintroducing an older central nervous system depressant could draw scrutiny from regulators, prescribers, and insurers even if a modern formulation reduced certain risks.

Does methyprylon have biosimilar risk?

No. Biosimilar risk does not apply because methyprylon is a small-molecule chemical drug, not a biologic. The relevant competitive threats are generic substitution and therapeutic replacement.

A future methyprylon product would compete with:

• Generic benzodiazepines.
• Generic zolpidem and related hypnotics.
• Orexin receptor antagonists.
• Sedating antidepressants.
• Over-the-counter sleep products.
• Nonpharmacologic insomnia treatments.

The absence of biosimilar exposure does not improve the asset’s economics. Generic and therapeutic competition would remain extensive.

What patent litigation and settlement agreements affect methyprylon?

No active patent litigation or settlement agreement materially affects methyprylon’s current market position. There is no evident modern litigation framework involving:

• Orange Book-listed patents.
• Paragraph IV certifications.
• Authorized generic launches.
• Patent settlements delaying generic entry.
• License agreements controlling market access.

Historical manufacturer, distributor, or patent transactions may exist in archival records, but they do not create current commercial barriers or value. No notable recent licensing deal appears to have revived the asset.

How does methyprylon compare with modern insomnia drugs?

Factor	Methyprylon	Zolpidem	Temazepam	Orexin antagonists
Current U.S. market	No active market	Established generic market	Established generic market	Active branded market
Patent position	Expired or irrelevant	Mostly expired, with product-specific history	Expired	Active or recently active product estates
Regulatory familiarity	Historical only	High	High	Current
Physician adoption	Minimal	Broad	Selective	Growing in defined segments
Generic competition	No current product	High	High	Lower for protected products
Commercial opportunity	Negligible	Mature, volume-driven	Mature, limited	Potentially higher, depending on product
Reintroduction burden	Very high	Not applicable	Not applicable	Not applicable

Methyprylon is disadvantaged on every major commercial metric: regulatory relevance, safety perception, physician familiarity, reimbursement, and intellectual property. Its only structural advantage would be that legacy molecule patents do not constrain a new entrant. That advantage has little value without a clinically differentiated product.

What generic launch scenarios exist for methyprylon?

A conventional generic launch is unlikely because there is no active reference product creating an ordinary ANDA pathway. Three scenarios are theoretically possible:

1. A sponsor identifies a current approved reference product and pursues an ANDA. This appears impractical for a discontinued product with no active U.S. reference listing.
2. A sponsor submits a 505(b)(2) application relying partly on published or historical data while developing a new formulation.
3. A sponsor pursues a full new drug application with modern clinical and safety evidence.

The third scenario would carry the highest cost and regulatory risk. The second could reduce development burden but would still require a commercially meaningful differentiation strategy.

What is the geographic coverage of methyprylon?

Methyprylon’s historical presence was broader than its current market status. It was used in multiple countries during the mid-20th century, but its commercial availability has contracted substantially.

Region	Current commercial assessment
United States	No active mainstream pharmaceutical market identified
European markets	No established current product identified
Canada	No material current market identified
Japan	No material current market identified
Emerging markets	Historical or isolated availability may exist, but no significant regulated-market franchise is evident
Global	Commercially obsolete and strategically inactive

Country-level availability should be distinguished from legal possession or isolated importation. A product can appear in chemical catalogs or archival drug databases without being approved, manufactured, or legally marketed as a medicine.

Key Takeaways

• Methyprylon is a discontinued piperidinedione sedative-hypnotic historically marketed as Noludar.
• Its commercial use declined after benzodiazepines and newer hypnotics became available.
• Original compound and product patents expired decades ago.
• No active Orange Book patent estate, Paragraph IV dispute, or current generic-entry litigation is associated with methyprylon.
• The FDA has no current mainstream commercial methyprylon product comparable to an active reference-listed drug.
• No biosimilar risk exists because methyprylon is a small-molecule drug.
• Current pharmaceutical revenue is effectively zero.
• A relaunch would require a new regulatory and clinical strategy, most plausibly under a 505(b)(2) or full NDA pathway.
• The principal barriers are safety perception, clinical redevelopment, liability, weak reimbursement prospects, and competition from inexpensive generic hypnotics.
• Methyprylon has negligible present-day licensing, investment, or patent value unless paired with a genuinely differentiated delivery system or medical use.

FAQs About Methyprylon Market and Patent Status

Is methyprylon still prescribed for insomnia?

No established mainstream prescribing market exists for methyprylon in the United States or other major regulated pharmaceutical markets. Modern treatment has shifted to newer hypnotics, behavioral therapy, and alternative pharmacologic options.

Is Noludar still manufactured?

Noludar, the historical brand associated with methyprylon, is not an active mainstream commercial product. Current manufacturing and distribution would require country-specific regulatory authorization.

Can a company obtain a patent on methyprylon?

A company generally could not obtain a new broad patent on the old methyprylon molecule itself. It might pursue protection for a novel formulation, manufacturing process, combination, delivery system, or medical use if the invention met applicable patentability standards.

Is methyprylon a controlled substance?

Methyprylon has central nervous system depressant and dependence-related concerns, but legal scheduling differs by jurisdiction. Its historical classification should be checked against the law of the country where possession, manufacture, or distribution is contemplated.

Would methyprylon be commercially attractive as a reformulated drug?

The commercial case is weak. A reformulated product would need to demonstrate a clear safety, efficacy, adherence, or delivery advantage over generic hypnotics and current branded sleep medicines.

References

1. DrugBank. (n.d.). Methyprylon. DrugBank Online.
2. National Center for Biotechnology Information. (n.d.). Methyprylon. PubChem Compound Summary. U.S. National Library of Medicine.
3. U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations: Orange Book.
4. World Health Organization. (1971). WHO Expert Committee on Drug Dependence: Sixteenth report. WHO Technical Report Series.
5. U.S. Food and Drug Administration. (n.d.). Discontinued drugs and products withdrawn or removed from the market. FDA.