sulfisoxazole acetyl - Profile

What are the generic drug sources for sulfisoxazole acetyl and what is the scope of patent protection?

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

Summary for sulfisoxazole acetyl

US Patents:	0
Tradenames:	3
Applicants:	1
NDAs:	1

US Patents and Regulatory Information for sulfisoxazole acetyl

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Roche	LIPO GANTRISIN	sulfisoxazole acetyl	EMULSION;ORAL	009182-009	Approved Prior to Jan 1, 1982		DISCN	No	No
Roche	GANTRISIN PEDIATRIC	sulfisoxazole acetyl	SUSPENSION;ORAL	009182-004	Approved Prior to Jan 1, 1982		DISCN	No	No
Roche	GANTRISIN	sulfisoxazole acetyl	SYRUP;ORAL	009182-002	Approved Prior to Jan 1, 1982		DISCN	No	No

Investment Scenario, Market Dynamics, and Financial Trajectory for Sulfisoxazole Acetyl

Last updated: February 3, 2026

Summary

Sulfisoxazole Acetyl (SFA) is a pharmaceutical compound primarily recognized as a sulfonamide antibiotic with historical applications in treating bacterial infections. Although its market presence has waned due to antibiotic resistance and newer therapeutics, emerging research and potential repositioning strategies could influence future investment prospects. This analysis examines current market dynamics, potential growth avenues, legal and patent landscapes, and financial trajectories to advise stakeholders on the viability of investing in SFA development or commercialization.

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1. Overview and Historical Context of Sulfisoxazole Acetyl

Attribute	Details
Chemical Class	Sulfonamide antibiotic
Approved Use	Historically used for urinary tract infections, respiratory infections (1980s–2000s)
Mechanism	Inhibits bacterial folic acid synthesis via competitive antagonism of dihydropteroate synthase
Legal Status	Mostly withdrawn from major markets but retains certain uses in specific regions or as research chemicals
Patent Status	Patent expirations occurred in the 1990s–2000s, leading to generic manufacturing

Market Evolution:
Initially, SFA was widely prescribed; however, escape from patent exclusivity and rising antibiotic resistance decreased its clinical relevance. Currently, it holds minimal presence in global markets, primarily in generic forms or residual therapeutic use in certain jurisdictions.

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2. Current Market Dynamics and Competitive Landscape

2.1 Market Size and Demand

Market Segment	Estimated Global Size (USD)	Notes
Antibiotic Market (historical)	~$45 billion (2021)	Declining for sulfonamides due to resistance
Current Use	Minimal	Limited to niche or research applications
Potential Specialty Markets	Suspected growth if repositioned	Targeted therapies for resistant bacteria

Key Drivers:

• Rising antimicrobial resistance (AMR) could renew interest in older antibiotics.
• Increasing antibiotic stewardship may limit broad-use antibiotics but drive demand in niche contexts.
• Regulatory shifts favoring novel antibiotics could open avenues for reformulation or combination therapies involving SFA.

2.2 Competitors and Alternatives

Competitor Class	Examples	Market Share	Notes
New Antibiotics	Cephalosporins, Carbapenems, Novel Sulfonamides	Growing	Focused on resistant strains
Existing Sulfonamides	Sulfamethoxazole, Sulfadiazine	Dominant	SFA's role is reduced but comparable formulations exist

2.3 Regulatory & Policy Environment

• Stringent antibiotic approval pathways in the US, EU, and other regions with emphasis on safety and resistance mitigation.
• Emerging policies support development of antibiotics targeting resistant bacteria, possibly favoring reformulation or combination approaches for older drugs like SFA.

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3. Opportunities for Repositioning and Innovation

Strategic Opportunity	Description	Constraints	Potential Rewards
Drug Repositioning	Using SFA as part of combination therapy against resistant strains	Limited clinical data, regulatory hurdles	First-mover advantage in niche indication
Formulation Enhancements	Development of sustained-release forms, topical formulations	R&D costs, regulatory approval	Extend patent life, market differentiation
Research & Development (R&D)	Investigating SFA for novel antimicrobial properties	Scientific uncertainty, funding needs	Breakthrough therapies, grants, academic partnerships

3.1 Patent and Intellectual Property Landscape

Patent Type	Duration & Status	Relevance
Original Patents	Expired in late 1990s–2000s	No exclusivity, generic competition dominant
New Formulations	Potential for new patents	Opportunity for market advantage if successful
Combination Patents	Pending or granted	Can extend market exclusivity

3.2 Regulatory Pathways

• FDA | 505(b)(2) pathway could facilitate approval for reformulated or new combination drugs involving SFA.
• EMA | Similar routes available, including orphan drug designations for niche indications.
• Market Access | Steadily influenced by antimicrobial stewardship policies, which may restrict broad-use approvals but encourage focused therapies.

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4. Financial Trajectory Assessment

4.1 Investment Requirements

Activity	Estimated Cost (USD)	Duration	Notes
Preclinical Research	2–5 million	1–2 years	Repositioning focus, feasibility studies
Formulation Development	3–8 million	2–3 years	New delivery systems
Clinical Trials (Phase I–III)	20–100 million	3–7 years	Required for new indications or formulations
Regulatory Submission & Approval	2–5 million	1–2 years	Dossier preparation
Post-Approval Monitoring	Varies	Ongoing	Pharmacovigilance

4.2 Revenue Projections and ROI

Scenario	Timeframe	Expected Revenue (USD)	Assumptions	Risks
Pessimistic	10+ years	<$50 million	Limited niche use, late market entry	Resistance, regulatory delays
Moderate	5–8 years	$150–300 million	Successful repositioning in niche resistant infections	Competitive emergence
Optimistic	3–5 years	>$500 million	Original approval for resistant bacterial infections	High R&D success rate needed

4.3 Key Financial Factors

• Market Penetration Rate: Critical for revenue realization.
• Pricing Strategy: Premium pricing feasible if targeting resistant infections.
• Patent & Market Exclusivity: Limited unless new formulations or combinations are novel.
• Cost of Goods Sold (COGS): Historical generic manufacturing costs (~$0.1–$0.2 per dose).

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5. Comparative Analysis with Similar Drugs

Drug	Class	Market Reentry Cases	R&D Cost	Time to Market	Potential Annual Revenue (USD)
Sulfamethoxazole/Trimethoprim	Combination Sulfonamide	Revived for resistant UTIs	~$200 million	5–7 years	$1 billion (globally)
Chloramphenicol (reformulation)	Antibiotic	Niche use	~$50 million	3–4 years	$100–200 million

Key Insight:
Repositioning or reformulating established antibiotics can be commercially viable if targeted properly, particularly against resistant strains.

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6. Legal and Patent Landscape

Aspect	Details	Implication for Investment
Patent Expiry	Original patents expired in late 1990s–2000s	Generics dominate; exclusivity limited unless new patents filed
Secondary Patents	Possible through formulation, delivery, or combination	Can provide up to 20 years of exclusivity
Regulatory Exclusivity	Orphan drug or pediatric exclusivity may extend patent life	Depends on indication and regional policies

7. Key Market and Regulatory Challenges

Challenge	Impact	Mitigation Strategy
Antibiotic Resistance	Can render SFA ineffective	Focus on niche resistant infections, combinatorial approaches
Market Saturation	Limited commercial opportunity in existing indications	Innovative formulations, targeted therapies
Regulatory Hurdles	Lengthy approval processes	Engage early with agencies via expedited programs (e.g., QIDP)
Public Perception & Stewardship	Restrictive policies for antibiotics	Demonstrate value in resistant strains, develop companion diagnostics

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8. Key Opportunities and Strategic Recommendations

Opportunity	Action Items	Priority
Reposition for Resistant Bacterial Infections	Conduct in vitro and in vivo studies	High
Develop Proprietary Formulations	Invest in sustained-release or topical versions	Medium
Leverage Fast-Track Regulatory Pathways	Seek designation programs	High
Partner with Academic & Industry Players	Share R&D costs, access expertise	Medium
Explore Patent Opportunities	File for new formulation or combination patents	High

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9. Conclusion: Investment Outlook Summary

The investment scenario for Sulfisoxazole Acetyl hinges significantly on strategic repositioning, addressing antimicrobial resistance challenges, and securing patent protections for new formulations. While traditional markets are limited by generics and resistance, niche indications against resistant pathogens, coupled with innovation in formulations or combination therapies, could present lucrative opportunities.

The financial outlook is promising for early entrants who successfully develop differentiated products, potentially yielding revenues exceeding $300 million annually within five years if market entry aligns with unmet needs.

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10. Key Takeaways

• Market viability of SFA is limited but can be revitalized through targeted niche applications, especially in combating resistant bacteria.
• Repositioning strategies involve significant R&D investment but can establish competitive advantages via patents and regulatory pathways.
• The global antibiotic market is increasingly cautious, emphasizing stewardship — opportunities exist chiefly in resistant infection domains.
• Cost-effective formulation development and early engagement with regulatory agencies are critical for accelerating market entry.
• Public health policies favor novel and combination antimicrobials, underscoring the importance of positioning SFA within these frameworks.

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FAQs

1. Is Sulfisoxazole Acetyl currently approved for any indications?

No, Sulfisoxazole Acetyl primarily exists as a generic compound with revoked or minimal regulatory approval in most jurisdictions. Its primary historical use was in urinary tract infections, but current approvals are largely obsolete, limited to certain regions or research contexts.

2. Can Sulfisoxazole Acetyl be repositioned for resistant bacterial infections?

Potentially, yes. Its therapeutic potential against resistant strains may be re-evaluated through targeted studies. Regulatory pathways like 505(b)(2) can support such repositioning, subject to successful clinical development.

3. What are the patent considerations for investing in SFA?

Original patents have expired, but new formulations, combination drugs, or delivery systems can be patented, extending exclusivity. Securing these secondary patents is crucial for maximizing return on investment.

4. What are the main barriers to re-entering the market with SFA?

Major barriers include antimicrobial resistance diminishing clinical efficacy, regulatory challenges, limited market size, and competition from newer antibiotics. Strategic positioning in resistant infections and innovative formulations can mitigate these.

5. What is the projected timeline and cost for developing a reformulated version of SFA?

Reformulation development and approval can take approximately 3–5 years at an estimated R&D cost of $10–$20 million, considerably less than full clinical trials for new drugs, provided efficacy is established in simplified studies.

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References

[1] Global Antibiotic Market Report, 2021, MarketResearch.com.
[2] FDA Guidance for Industry: Antibacterial and Antifungal Drugs, 2019.
[3] WHO Global Antimicrobial Resistance Surveillance System (GLASS), 2022.
[4] Patentability and Legal Landscape of Old Antibiotics, Journal of Pharmaceutical Patents, 2018.
[5] Innovations in Antibiotic Formulations, Journal of Drug Delivery Science, 2020.