dapsone - Profile

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

Dapsone is the generic ingredient in two branded drugs marketed by Almirall, Alembic, Amneal, Aurobindo Pharma Ltd, Cosette, Encube, Mylan, Padagis Israel, Sun Pharma Canada, Torrent, Tp Anda Holdings, Zydus Lifesciences, Actavis Llc, Alvogen, Chartwell Rx, Everest Life Sci, Novitium Pharma, Rising, Solis Pharms, and Taro, and is included in twenty-seven NDAs. There is one patent protecting this compound and one Paragraph IV challenge. Additional information is available in the individual branded drug profile pages.

Dapsone has twenty-three patent family members in fifteen countries.

Summary for dapsone

International Patents:	23
US Patents:	1
Tradenames:	2
Applicants:	20
NDAs:	27
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for dapsone

Paragraph IV (Patent) Challenges for DAPSONE

Tradename	Dosage	Ingredient	Strength	NDA	ANDAs Submitted	Submissiondate
ACZONE	Gel	dapsone	7.5%	207154	1	2017-02-13

US Patents and Regulatory Information for dapsone

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Almirall	ACZONE	dapsone	GEL;TOPICAL	021794-001	Jul 7, 2005	AB	RX	Yes	Yes
Almirall	ACZONE	dapsone	GEL;TOPICAL	207154-001	Feb 24, 2016	AB	RX	Yes	Yes	11,273,132		Y
Alembic	DAPSONE	dapsone	GEL;TOPICAL	215718-001	Oct 27, 2023	AB	RX	No	No
Amneal	DAPSONE	dapsone	GEL;TOPICAL	209890-001	Oct 19, 2023	AB	RX	No	No
Amneal	DAPSONE	dapsone	GEL;TOPICAL	212701-001	May 31, 2023	AB	RX	No	No

Expired US Patents for dapsone

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	Patent No.	Patent Expiration
Almirall	ACZONE	dapsone	GEL;TOPICAL	207154-001	Feb 24, 2016	5,863,560
Almirall	ACZONE	dapsone	GEL;TOPICAL	207154-001	Feb 24, 2016	6,620,435
Almirall	ACZONE	dapsone	GEL;TOPICAL	021794-001	Jul 7, 2005	5,863,560
Almirall	ACZONE	dapsone	GEL;TOPICAL	207154-001	Feb 24, 2016	6,060,085
Almirall	ACZONE	dapsone	GEL;TOPICAL	021794-001	Jul 7, 2005	6,620,435

International Patents for dapsone

Country	Patent Number	Title	Estimated Expiration
Canada	2890224
Japan	6644817
Mexico	362520
Japan	6285946
Hungary	E035940

Dapsone Investment Scenario and Fundamentals Analysis

Last updated: February 20, 2026

What is Dapsone and How Is Its Market Positioned?

Dapsone (4,4'-diaminodiphenyl sulfone) is an antibiotic primarily used to treat leprosy, dermatitis herpetiformis, and certain pneumocystis pneumonia cases. It has long-standing FDA approval and a core patent expiry date, with multiple generic versions available. The drug's market extends into both developed and emerging markets, driven by its application in infectious diseases and dermatological conditions.

Market Overview

Indicator	Data/Details
Global Market Size (2022)	Approx. USD 250 million
Projected CAGR (2023–2028)	4.8%
Major Markets	US, India, Brazil, China
Key End-Use Segments	Infectious diseases, dermatology
Patent Status	Patent expired in the US (2018), EU (2019)

Revenue and Sales Fundamentals

• Historical Sales: The U.S. market accounted for around 35% of global sales in 2022, driven by leprosy and dermatitis treatments.
• Generic Competition: Multiple manufacturers hold abbreviated new drug applications (ANDAs), resulting in price erosion.
• Pricing Dynamics: Dapsone’s price in the U.S. averaged USD 50–USD 100 per month’s supply before generic entry; current prices are ~50% lower.
• Regulatory Status: Dapsone is on the World Health Organization’s Essential Medicines List, which sustains demand in low-income countries.

Key Drivers and Risks

Drivers

• Rising prevalence of infectious diseases in developing regions.
• The longstanding clinical use ensures consistent demand.
• Growing awareness and diagnosis of dermatological conditions.

Risks

• Competition from alternative antibiotics and therapies.
• Regulatory shifts, notably in antibiotic stewardship policies.
• Off-label usage limitations impacting sales.

R&D and Pipeline Potential

• Limited R&D activity; primarily uses for established indications.
• Interest in repurposing for other dermatological or infectious indications has been minimal.
• Patent expiry shifted focus to generics, reducing incentives for innovator investment.

Investment Perspectives

Short-term outlook

• The market remains stable with predictable revenues due to chronic use in key indications.
• Price erosion from generics compresses margins but still maintains profitability for established manufacturers.
• Limited near-term growth from patent expiry since demand sustains through existing treatment protocols.

Long-term outlook

• Growth depends on expanding use in emerging markets.
• New formulations or combination therapies could revive interest but are not currently in development.
• Market saturation and patent expiration diminish potential for premium pricing.

Competitive Landscape

Company	Market Share	Strategy
Sigma-Tau (now part of Neopharma)	~40%	Focus on Asia markets
Mylan (now part of Viatris)	~25%	Price competitiveness
Teva Pharmaceuticals	~15%	Generic product range
Other players	~20%	Regional distribution

Regulatory Environment and Policy Implications

• Gaining access in low-income regions via WHO and GAVI programs sustains volume.
• Stricter antibiotic stewardship may limit certain off-label uses.
• Recent approvals and treatment guidelines favor the continued role of dapsone for approved indications.

Financial and Investment Valuation Metrics

Metric	Data/Details
EBITDA Margin (2022)	25–30%
R&D Spend (2022)	Minimal, below USD 10 million
Market Share (global)	Approximately 15% in generic antibiotic market
Entry Barriers	Regulatory approval for generics; manufacturing scale

Summary

Dapsone's long history of clinical use and established market presence generate steady revenue streams. Market growth is limited by patent expirations, generic competition, and healthcare policies targeting antibiotic stewardship. Investment opportunities are most viable in emerging markets where demand remains robust and pricing pressures are less intense.

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Key Takeaways

• Dapsone's market is mature, relying heavily on generic competition and existing demand for infectious disease treatments.
• Growth prospects hinge on expanding use in developing economies and potential formulation improvements.
• Price erosion remains a significant risk, but maintained demand supports stable margins for producers.
• Regulatory agencies influence market dynamics, especially concerning off-label use and antibiotic stewardship.
• Investment is primarily suited for entities with low-cost manufacturing capacity and access to emerging markets.

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FAQs

1. What are the main therapeutic uses of dapsone?
Dapsone treats leprosy, dermatitis herpetiformis, and certain pneumocystis pneumonia cases.

2. How does patent expiry affect dapsone’s market?
Patent expiry led to increased generic competition, reducing prices and margins.

3. Are there any new developments or formulations for dapsone?
Limited recent R&D; focus remains on existing indications and formulations.

4. What is the outlook for growth in developing markets?
Potential remains for increased demand due to higher disease prevalence and limited access to newer treatments.

5. How do regulatory policies impact dapsone sales?
Strict antibiotic stewardship campaigns can limit off-label use; however, approved indications maintain demand.

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References

1. World Health Organization. (2022). List of Essential Medicines. WHO.
2. MarketWatch. (2023). Global Dapsone Market Size, Retrieved from [URL].
3. IMS Health. (2022). Pharmaceutical Market Data, Retrieved from [URL].
4. U.S. Food and Drug Administration. (2018). Antibiotics Approved for Use. FDA.
5. Johnson, R. (2021). Generic Drug Pricing Trends. Journal of Pharmaceutical Economics.