Aspirin; pentazocine hydrochloride - Generic Drug Details

What are the generic drug sources for aspirin; pentazocine hydrochloride and what is the scope of freedom to operate?

Aspirin; pentazocine hydrochloride is the generic ingredient in one branded drug marketed by Sanofi Aventis Us and is included in one NDA. Additional information is available in the individual branded drug profile pages.

Summary for aspirin; pentazocine hydrochloride

US Patents:	0
Tradenames:	1
Applicants:	1
NDAs:	1
DailyMed Link:	aspirin; pentazocine hydrochloride at DailyMed

Anatomical Therapeutic Chemical (ATC) Classes for aspirin; pentazocine hydrochloride

N02AD	Benzomorphan derivatives
N02A	OPIOIDS
N02	ANALGESICS
N	Nervous system

US Patents and Regulatory Information for aspirin; pentazocine hydrochloride

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Sanofi Aventis Us	TALWIN COMPOUND	aspirin; pentazocine hydrochloride	TABLET;ORAL	016891-001	Approved Prior to Jan 1, 1982		DISCN	Yes	No

Expired US Patents for aspirin; pentazocine hydrochloride

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	Patent No.	Patent Expiration
Sanofi Aventis Us	TALWIN COMPOUND	aspirin; pentazocine hydrochloride	TABLET;ORAL	016891-001	Approved Prior to Jan 1, 1982

Aspirin and Pentazocine Hydrochloride Market Dynamics, Patent Status, and Financial Outlook

Last updated: September 17, 2026

The aspirin and pentazocine hydrochloride combination is a legacy opioid-analgesic product historically marketed as Talwin Compound. Its commercial value is now limited. The product has no identifiable modern patent moat, no biosimilar exposure, no material disclosed standalone revenue, and limited current market relevance because of opioid controls, safer analgesic alternatives, and uncertain commercial availability.

What is aspirin and pentazocine hydrochloride?

Aspirin and pentazocine hydrochloride is an oral combination analgesic containing an opioid agonist-antagonist and a nonsteroidal anti-inflammatory drug. Historical labeling for Talwin Compound identified pentazocine hydrochloride and aspirin as the active ingredients, with pentazocine providing opioid analgesia and aspirin providing analgesic and anti-inflammatory activity.[1]

Pentazocine is a Schedule IV controlled substance in the United States. It has mixed opioid pharmacology, including activity at kappa receptors and weaker activity at the mu receptor. The combination was developed for moderate pain, but its clinical and commercial position has deteriorated as prescribing shifted toward nonopioid analgesics, newer opioid formulations, and tightly controlled pain-management protocols.

Attribute	Product profile
Active ingredients	Aspirin and pentazocine hydrochloride
Historical brand	Talwin Compound
Drug class	Opioid analgesic and salicylate analgesic
Dosage form	Oral tablet
Regulatory category	Prescription drug; pentazocine is controlled
Biologic status	Not applicable
Biosimilar pathway	Not applicable
Current commercial position	Legacy or discontinued-market product
Principal market barriers	Controlled-substance regulation, limited demand, generic competition, clinical substitution

What is the FDA regulatory status of aspirin and pentazocine hydrochloride?

The product is a legacy small-molecule combination rather than a commercially important current FDA product. Historical FDA labeling and product databases identify aspirin/pentazocine products, but current availability must be distinguished from historical approval status. A product can remain in FDA records after commercial discontinuation.

The FDA’s Drugs@FDA and Orange Book systems are the principal sources for determining whether a specific reference-listed drug, abbreviated new drug application, or patent listing remains active.[2,3] For this combination, the regulatory record does not establish a meaningful current branded market comparable with active opioid products such as oxycodone, hydrocodone, or buprenorphine formulations.

FDA regulatory milestones

Regulatory issue	Assessment
Original approval	Historical FDA approval of pentazocine-containing products is documented
Current branded franchise	No material active branded franchise is apparent
Combination status	Legacy aspirin/pentazocine product
Controlled-substance status	Pentazocine is Schedule IV in the United States
Current demand	Narrow and declining relative to historical use
FDA exclusivity	No current regulatory exclusivity of commercial importance identified

Pentazocine products also face additional scrutiny because opioid labeling, dispensing, abuse-deterrence measures, and controlled-substance monitoring affect prescribing and distribution. Aspirin adds gastrointestinal bleeding, renal, and platelet-inhibition risks that reduce the attractiveness of the combination for long-term use.

When does aspirin and pentazocine lose exclusivity?

The combination lost practical market exclusivity decades ago. Any patent protection associated with the original active ingredients, early formulations, or historical product development would have expired under the patent terms applicable at the time of filing.

Exclusivity category	Current position
Original compound patent	Expired
Historical formulation patents	Expired or commercially immaterial
FDA chemical exclusivity	Expired
FDA orphan exclusivity	Not applicable
Pediatric exclusivity	Not applicable
Patent term extension	No commercially relevant extension identified
Current Orange Book patent barrier	No active barrier of material commercial significance identified

A modern generic applicant would not be competing against a protected new chemical entity. The relevant issues would be product availability, reference-listed-drug status, bioequivalence, controlled-substance requirements, and manufacturing economics.

What patents protect aspirin and pentazocine hydrochloride?

No active patent estate with meaningful commercial blocking power has been identified for the historical aspirin/pentazocine combination. The active ingredients are old, and the product’s historical development predates the modern patent-term framework.

The patent position can be summarized as follows:

Patent category	Commercial assessment
Aspirin composition patents	Expired
Pentazocine composition patents	Expired
Combination product patents	Any historical rights are expired
Controlled-release formulation patents	No current product-specific barrier identified
Method-of-use patents	No current enforceable exclusivity identified
Manufacturing patents	No publicly visible barrier likely to prevent generic production
Orange Book patents	No material current listing identified

The absence of a current patent moat does not mean that every manufacturing process is freely interchangeable. A manufacturer may still hold confidential process know-how, supplier qualifications, analytical methods, or controlled-substance compliance systems. Those factors are operational barriers, not product exclusivity.

What formulation patents protect the product?

Historical aspirin/pentazocine products were conventional oral tablets. The formulation did not establish the type of long-duration or abuse-deterrent platform that can support later patent filings.

Potential formulation issues include:

• Tablet hardness and dissolution.
• Protection of aspirin from degradation.
• Uniform distribution of low-dose pentazocine within the tablet.
• Stability of the combined active ingredients.
• Packaging that limits moisture exposure.
• Controlled-substance inventory and serialization controls.

These issues can affect manufacturing cost and regulatory filing complexity. They are unlikely to support meaningful exclusivity because the dosage form is technically mature and the active ingredients are well characterized.

Are there Paragraph IV challenges for aspirin and pentazocine hydrochloride?

No material, current Paragraph IV litigation involving the historical aspirin/pentazocine combination is apparent in the public patent-litigation record. That outcome is consistent with the product’s age and the absence of an important unexpired patent estate.

A generic applicant could use an ANDA pathway if an eligible reference-listed drug and applicable product-specific requirements are available. The principal filing questions would involve:

1. Whether an active reference product is listed.
2. Whether the proposed strength and dosage form match the reference.
3. Whether FDA requires a different regulatory pathway because of listing or availability issues.
4. Whether the applicant can meet controlled-substance manufacturing and distribution requirements.
5. Whether the commercial opportunity justifies development costs.

A Paragraph IV strategy would have little value where no blocking patent remains. The more relevant risk is regulatory and commercial execution rather than patent litigation.

What generic entry risks exist?

Generic entry risk is structurally high because the active ingredients are old and the historical product lacks meaningful patent protection. Commercial entry risk is more complicated because demand is small and the product may not have a stable active market.

Generic-entry factor	Risk level	Effect
Patent blocking risk	Low	No material unexpired estate identified
Regulatory complexity	Moderate	Combination product and controlled opioid requirements
Manufacturing complexity	Low to moderate	Conventional tablet, but controlled-substance controls apply
Market size	Low	Narrow prescribing base
Pricing pressure	High	Mature generic analgesic category
Supply-chain risk	Moderate	Controlled-substance quotas and supplier concentration
Probability of attractive returns	Low	Small addressable market and weak differentiation

A generic launch could succeed if a manufacturer has an existing controlled-substance platform, low incremental development costs, and access to established wholesale channels. A standalone entrant would face weak economics.

How strong is the patent estate for aspirin and pentazocine hydrochloride?

The patent estate is weak from an investment and licensing perspective. It lacks the characteristics that typically support premium pharmaceutical valuation:

• No unexpired composition-of-matter protection.
• No recognized extended-release platform.
• No current method-of-use exclusivity.
• No biologic manufacturing complexity.
• No meaningful regulatory exclusivity.
• No visible litigation leverage.
• No clear branded pricing power.

The remaining defensibility is operational. It may include manufacturing know-how, controlled-substance procurement, regulatory history, and distribution relationships. These assets can preserve a niche business but do not create durable market exclusivity.

What is the Orange Book status of aspirin and pentazocine hydrochloride?

The Orange Book is relevant for identifying approved drug products, reference-listed drugs, therapeutic equivalents, and listed patents. The practical Orange Book conclusion for aspirin/pentazocine is that historical presence should not be treated as evidence of an active commercial franchise.

Orange Book question	Answer
Is the product historically represented in FDA records?	Yes, historical pentazocine combination records exist
Is there a current high-value patent listing?	None of material commercial significance identified
Is there current brand exclusivity?	No
Is the product a biologic?	No
Does biosimilar substitution apply?	No
Is generic substitution commercially relevant?	Only if a currently marketable reference and supply opportunity exist

Orange Book status must be checked by exact product strength, dosage form, application number, and marketing status. Historical approval records alone do not establish current supply.

Which companies are challenging or competing with the product?

There is no meaningful current branded patent contest around aspirin/pentazocine. Competition comes from therapeutic substitutes rather than direct patent challengers.

Direct and indirect competitors

Competitor category	Examples	Competitive effect
Nonopioid analgesics	Aspirin, ibuprofen, naproxen, acetaminophen	Reduce use for mild and moderate pain
Conventional opioids	Hydrocodone, oxycodone, codeine	Compete for prescription analgesia
Mixed-mechanism opioids	Tramadol, buprenorphine	Offer different risk and dosing profiles
Topical products	Diclofenac gel, lidocaine products	Capture localized pain treatment
Specialty pain therapies	Neuropathic pain agents and interventional care	Reduce chronic use of older opioid combinations

The strongest competitive pressure comes from treatment substitution. Prescribers have less incentive to use an older opioid-salicylate combination when separate dosing, nonopioid options, or more standardized opioid products are available.

What is the financial trajectory and revenue exposure?

No reliable standalone revenue series for aspirin/pentazocine hydrochloride is publicly disclosed. The product is not reported as a separate material revenue line by major pharmaceutical companies, and historical sales data are generally embedded within broader analgesic portfolios.

The financial trajectory is therefore best assessed by market structure:

Financial metric	Assessment
Current branded revenue	Not publicly disclosed and likely immaterial
Historical peak revenue	Not reliably disclosed at product level
Revenue growth	Negative or inactive-market profile
Gross-margin potential	Limited by generic pricing
Pricing power	Minimal
Reimbursement leverage	Low
Licensing value	Low unless bundled with an existing controlled-substance platform
Litigation value	Minimal
Terminal commercial value	Niche or negligible

For an originator, current revenue exposure is likely limited to residual distribution, licensing, or portfolio accounting. For a generic manufacturer, the product could generate incremental revenue but is unlikely to support a large development program without shared manufacturing infrastructure.

Are there licensing deals or settlement agreements?

No significant recent licensing deal or Paragraph IV settlement associated with aspirin/pentazocine hydrochloride is identified in the public record. The product’s age and lack of active patent protection reduce the probability of commercially important settlement activity.

Any historic transfer of rights would more likely have occurred through broader analgesic portfolio transactions rather than a standalone transaction centered on this combination. Such transactions should not be interpreted as evidence of current product value.

What patent litigation affects the product?

No significant active patent litigation affecting the aspirin/pentazocine combination is apparent. Litigation risk is more likely to arise from:

• Controlled-substance compliance.
• Product liability.
• Failure-to-warn claims.
• Manufacturing or contamination issues.
• Distribution and diversion controls.
• Regulatory enforcement involving opioid handling.

These risks are separate from patent exclusivity and do not create a basis for premium valuation.

How does aspirin and pentazocine compare with newer analgesics?

Factor	Aspirin/pentazocine	Modern nonopioid therapy	Newer opioid or specialty product
Patent protection	None of material significance	Often expired or product-specific	May have formulation or use patents
Abuse-control burden	High	Low	Moderate to high
Clinical familiarity	Historical	High	Variable
Commercial differentiation	Low	Moderate by indication	Can be high for specialty products
Regulatory complexity	Moderate	Low to moderate	Moderate to high
Reimbursement appeal	Weak	Generally stronger	Depends on indication
Long-term market outlook	Declining or niche	Stable to growing in selected uses	Mixed

The combination’s main commercial disadvantage is that it combines the liabilities of an opioid with aspirin-related adverse-effect concerns without preserving meaningful intellectual-property differentiation.

What manufacturing and IP barriers remain?

Manufacturing barriers are more significant than patent barriers. A producer must manage pentazocine quota allocation, controlled-substance security, inventory reconciliation, DEA compliance, validated analytical methods, and reliable aspirin supply.

The product may also require:

• Demonstrated content uniformity.
• Stability data for both active ingredients.
• Dissolution testing for the finished tablet.
• Packaging that limits moisture and degradation.
• Controlled distribution and recordkeeping.
• Pharmacovigilance for opioid-related adverse events.

These requirements raise fixed costs but do not prevent entry by established generic manufacturers.

Key Takeaways

• Aspirin and pentazocine hydrochloride is a legacy oral analgesic combination historically associated with Talwin Compound.
• The product has no identified active patent estate with meaningful commercial blocking power.
• Composition, formulation, and method-of-use exclusivity are expired or commercially irrelevant.
• No material current Paragraph IV litigation, patent settlement, or licensing activity is apparent.
• Biosimilar risk does not apply because the product is a small-molecule combination.
• Current standalone revenue is not publicly disclosed and is likely immaterial.
• Generic entry risk is high from a patent perspective but constrained by limited demand and controlled-substance compliance.
• The main competitive threat comes from nonopioid analgesics, newer opioid products, and specialty pain therapies.
• The commercial opportunity is niche and is most viable for manufacturers that already possess controlled-substance infrastructure.

FAQs

Is aspirin and pentazocine hydrochloride still marketed in the United States?

It is principally a historical or legacy product. FDA records may retain approval or labeling information even when routine commercial supply is unavailable.

Is pentazocine more commercially important than the aspirin combination?

Yes. Pentazocine has had greater commercial relevance in standalone and naloxone-containing products than in the aspirin combination. The combination has limited current differentiation.

Can a generic company file an ANDA for aspirin and pentazocine?

Potentially, but the filing depends on an eligible reference-listed drug, matching strength and dosage form, FDA requirements, and controlled-substance manufacturing capability.

Does the combination have biosimilar competition?

No. Biosimilars apply to biologic products. Aspirin and pentazocine hydrochloride are synthetic small molecules regulated through generic-drug pathways.

What is the investment value of the product’s intellectual property?

The product’s direct intellectual-property value is low. Any residual value would derive from manufacturing capability, regulatory history, distribution access, or inclusion in a broader controlled-substance portfolio.

References

1. U.S. Food and Drug Administration. (n.d.). Talwin Compound: Pentazocine hydrochloride and aspirin tablet labeling. FDA drug labeling database. https://www.accessdata.fda.gov
2. U.S. Food and Drug Administration. (n.d.). Drugs@FDA: FDA-approved drugs. https://www.accessdata.fda.gov/scripts/cder/daf/
3. U.S. Food and Drug Administration. (n.d.). Approved drug products with therapeutic equivalence evaluations: Orange Book. https://www.fda.gov/drugs/drug-approvals-and-databases/orange-book
4. U.S. Drug Enforcement Administration. (n.d.). Controlled substances act. https://www.deadiversion.usdoj.gov
5. U.S. Food and Drug Administration. (n.d.). FDA opioid analgesic drugs and safety communications. https://www.fda.gov/drugs/information-drug-class/opioid-analgesic-drugs-related-safety-labeling-changes-postmarket-study-requirements-and-safety-issues