DARVOCET-N 50 Drug Patent Profile

Which patents cover Darvocet-n 50, and what generic alternatives are available?

Darvocet-n 50 is a drug marketed by Xanodyne Pharm and is included in one NDA.

The generic ingredient in DARVOCET-N 50 is acetaminophen; propoxyphene napsylate. There are sixty-six drug master file entries for this compound. Additional details are available on the acetaminophen; propoxyphene napsylate profile page.

Summary for DARVOCET-N 50

US Patents:	0
Applicants:	1
NDAs:	1

US Patents and Regulatory Information for DARVOCET-N 50

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Xanodyne Pharm	DARVOCET-N 50	acetaminophen; propoxyphene napsylate	TABLET;ORAL	017122-001	Approved Prior to Jan 1, 1982		DISCN	No	No

Summary: This analysis evaluates the investment outlook for DARVOCET-N 50, a combination analgesic historically used for moderate pain management. Key areas covered include the current market landscape, regulatory environment, competitors, patent status, and future financial projections. Given its market and regulatory status, the drug presents limited growth prospects and potential recall risks, impacting investment viability.

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Investment Scenario, Market Dynamics, and Financial Trajectory for DARVOCET-N 50

Overview and Historical Context

DARVOCET-N 50, a combination of propoxyphene napsylate and acetaminophen, was historically prescribed for analgesia. It was marketed primarily in the United States but was withdrawn from the market in 2010 following safety concerns related to cardiac toxicity (notably, arrhythmias and overdose risks). Despite its decline, residual market activities and patent status influence re-evaluation potential.

• Initial approval: 1957 (by FDA)
• Market withdrawal: 2010 (FDA recommendation)
• Revocation basis: Cardiotoxicity risk, especially with high doses
• Current status: Market withdrawn, minimal formal clinical use

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Market Dynamics of DARVOCET-N 50

Regulatory Environment

Aspect	Details
FDA Status	Market withdrawn in 2010; no approval for new sales; existing products phased out.
Legal:	Class action suits and recall orders reinforce regulatory stance.
Future reintroduction	Unlikely without reformulation demonstrating improved safety.

Current Market Landscape

Parameter	Details
Market presence	Virtually nonexistent in US and global markets since 2010.
Legal liabilities	High due to past litigation and safety concerns.
Reformulation potential	Minimal unless significant reformulation occurs to mitigate toxicity.

Competition

Competitor Drugs	Market Position	Notes
Acetaminophen-based combos	Market leaders	E.g., Tylenol with codeine, tramadol
NSAIDs	Alternatives	Ibuprofen, naproxen, diclofenac
Opioid analgesics	Market dominance	Oxycodone, hydrocodone, though with regulatory restrictions

Patent and Intellectual Property

Aspect	Details
Original patent expiration	1970s-1980s
Patent extensions	Not applicable; patent expired decades ago
Regulatory exclusivity	None in current context; market withdrawn

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Financial Trajectory and Investment Outlook

Historical Revenue and Sales Data

Year	U.S. Market Sales (USD millions)	Notes
2000	$150	Peak sales levels pre-withdrawal
2005	$100	Decline due to emerging safety concerns
2010	$0	Post-market withdrawal

Note: The decline correlates directly with FDA actions and safety issues.

Projected Future Revenue

Scenario	Assumptions	Figures	Time horizon
Status Quo	Market remains withdrawn	$0	Indefinite
Reintroduction with reformulation	New formulation, safety validations	Potential niche market	5-10 years
Repositioning in emerging markets	Limited potential, regulatory hurdles	<$10 million annually	10+ years

Investment Risks

• Regulatory dismissal: FDA unlikely to approve reformulated version without substantial safety data.
• Legal liabilities: Ongoing litigation could impose significant costs.
• Market Scarcity: No current demand, limited to legacy stock or legal settlements.
• Reformulation costs: High R&D and clinical trial expenses with uncertain approval outcomes.

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Comparative Analysis of Similar Drugs

Drug	Market Status	Main Concerns	Current Use	Potential for Re-emergence
Darvocet (Propoxyphene) Original	Withdrawn	Cardiac toxicity	None	Unlikely
Tcore succinate	Approved	Fewer safety issues	Used in specific regions	Moderate
Tramadol	Marketable	Less abuse potential	Widely used	High

This comparison demonstrates that reformulation and safety validation are prerequisites for any reintroduction.

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Regulatory and Ethical Considerations

• FDA: Strictly restricts drugs with adverse safety profiles.
• Legal liabilities: Potential for class action lawsuits limits market recovery.
• Ethical concerns: Prescribing risk outweighs benefits in current evidence base.

Regulatory Policies Impacting Investment

Policy	Impact	Reference
FDA Drug Safety Modernization Act (2012)	Increased scrutiny of safety signals	[2]
Recall and phase-out policies	Market discontinuation	[3]

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Conclusion: Investment Viability

Aspect	Evaluation
Market potential	Virtually zero in current form; re-entry contingent on reformulation and safety validation.
Legal risks	High, with ongoing liabilities.
Regulatory barriers	Prohibitive unless significant reformulation occurs.
Financial outlook	Negative in the short term; uncertain in long-term restoration scenarios.

Summary: The investment outlook for DARVOCET-N 50 remains bleak unless a robust reformulation is developed, passing safety and efficacy standards. Market re-entry prospects are minimal, and current legal liabilities significantly diminish valuation possibilities. Strategic consideration should prioritize safer, approved alternatives with proven market demand.

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Key Takeaways

• Regulatory and safety challenges dominate future prospects; market withdrawal in 2010 effectively ended commercial viability.
• Legal liabilities continue to pose a risk, with past litigation generating potential financial exposures.
• Reformulation and clinical validation are essential for potential reintroduction; achieving such could take 5-10 years.
• Alternatives and competitors dominate the analgesic market, reducing likelihood of niche repositioning for DARVOCET-N 50.
• Investment should be cautious, favoring firms focused on innovation with a clear pathway through regulatory systems and market demand.

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FAQs

1. Why was DARVOCET-N 50 withdrawn from the market?
Due to safety concerns, specifically its association with cardiac toxicity and overdose risks, the FDA recommended its withdrawal in 2010, citing the drug’s propensity to cause arrhythmia and accidental overdose.

2. Can DARVOCET-N 50 be reformulated for reapproval?
Potentially, yes. However, reformulation must demonstrate a significantly improved safety profile, undergo extensive clinical trials, and secure FDA approval—a process that could span several years and incur substantial costs.

3. What legal liabilities exist with DARVOCET-N 50?
Despite market withdrawal, numerous lawsuits alleged harm caused by the drug, including cardiac injury and overdose deaths. Any residual inventory or past settlements could still pose liabilities for holders or manufacturers.

4. Is there a residual market for DARVOCET-N 50?
No. The current market is effectively nonexistent due to regulatory outright withdrawal and the availability of safer alternatives.

5. Are there ongoing research efforts related to DARVOCET-N 50?
Limited. Most research has shifted towards alternative analgesics with better safety profiles, such as NSAIDs, tramadol, and newer opioids with lower abuse potential.

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References:

Last updated: February 3, 2026

[1] FDA Drug Safety Communication. (2010). "FDA recommends against the use of Darvon and Darvocet."
[2] Food and Drug Administration. (2012). "Drug Safety Modernization Act."
[3] US Government Accountability Office. (2013). "FDA's Recall Program."