ZOSYN Drug Patent Profile

When do Zosyn patents expire, and what generic alternatives are available?

Zosyn is a drug marketed by Wyeth Pharms and Baxter Hlthcare Corp and is included in two NDAs.

The generic ingredient in ZOSYN is piperacillin sodium; tazobactam sodium. There are sixteen drug master file entries for this compound. Seventeen suppliers are listed for this compound. Additional details are available on the piperacillin sodium; tazobactam sodium profile page.

Summary for ZOSYN

US Patents:	0
Applicants:	2
NDAs:	2

Paragraph IV (Patent) Challenges for ZOSYN

Tradename	Dosage	Ingredient	Strength	NDA	ANDAs Submitted	Submissiondate
ZOSYN	For Injection	piperacillin sodium; tazobactam sodium	12 g/1.5 g per vial (pharmacy bulk)	050684	1	2011-12-06

US Patents and Regulatory Information for ZOSYN

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Wyeth Pharms	ZOSYN	piperacillin sodium; tazobactam sodium	INJECTABLE;INJECTION	050684-001	Oct 22, 1993		DISCN	Yes	No
Baxter Hlthcare Corp	ZOSYN IN PLASTIC CONTAINER	piperacillin sodium; tazobactam sodium	INJECTABLE;INJECTION	050750-002	Feb 24, 1998		RX	Yes	Yes
Wyeth Pharms	ZOSYN	piperacillin sodium; tazobactam sodium	INJECTABLE;INJECTION	050684-004	Oct 22, 1993		DISCN	Yes	No
Wyeth Pharms	ZOSYN	piperacillin sodium; tazobactam sodium	INJECTABLE;INJECTION	050684-002	Oct 22, 1993		DISCN	Yes	No
Wyeth Pharms	ZOSYN	piperacillin sodium; tazobactam sodium	INJECTABLE;INJECTION	050684-003	Oct 22, 1993		DISCN	Yes	No
Baxter Hlthcare Corp	ZOSYN IN PLASTIC CONTAINER	piperacillin sodium; tazobactam sodium	INJECTABLE;INJECTION	050750-001	Feb 24, 1998		RX	Yes	Yes
Baxter Hlthcare Corp	ZOSYN IN PLASTIC CONTAINER	piperacillin sodium; tazobactam sodium	INJECTABLE;INJECTION	050750-003	Feb 24, 1998		RX	Yes	Yes

International Patents for ZOSYN

See the table below for patents covering ZOSYN around the world.

Country	Patent Number	Title	Estimated Expiration
Brazil	PI0409450	composições que contêm peperacilina e tazobactamo, úteis para injeção
Russian Federation	2322980	КОМПОЗИЦИИ, СОДЕРЖАЩИЕ ПИПЕРАЦИЛЛИН И ТАЗОБАКТАМ,ПРИМЕНИМЫЕ ДЛЯ ИНЪЕКЦИИ (PIPERACILLIN AND TAZOBACTAM-CONTAINING COMPOSITIONS USED FOR INJECTION)
Costa Rica	9792	COMPOSICIONES QUE CONTIENEN PIPERACILINA Y TAZOBACTAM UTILES PARA INYECCIONES (DIVISIONAL DE EXP. 8035)
United Kingdom	2400557	Inhibition of Particulate Formation in Piperacillin/Tazobactam Parenteral Combinations, using Aminocarboxylic Acid Chelating Agents
Germany	602004010862
Israel	171337	PHARMACEUTICAL COMPOSITIONS CONTAINING PIPERACILLIN AND TAZOBACTAM, USES THEREOF AND PROCESSES FOR THE PREPARATION THEREOF
Spain	2298672

Investment Scenario and Fundamentals Analysis for ZOSYN

Last updated: February 20, 2026

What is ZOSYN?

ZOSYN (piperacillin/tazobactam) is an antibiotic used against a broad spectrum of bacterial infections. It combines piperacillin, a beta-lactam antibiotic, with tazobactam, a beta-lactamase inhibitor, to counter bacterial resistance. It is primarily administered intravenously and indicated for complicated intra-abdominal infections, urinary tract infections, pneumonia, and skin infections.

Market Overview and Revenue Potential

Market Size and Growth

The global antibiotic market was valued at approximately USD 50 billion in 2021, with an expected compound annual growth rate (CAGR) of about 3.5% through 2028 [1]. ZOSYN accounts for roughly 15% of the hospital-based extended-spectrum penicillin market. Its revenue contribution depends on hospital usage, patent status, and generic competition.

Competitive Position

ZOSYN's main competitors include:

• Ceftriaxone-based therapies
• Carbapenems (e.g., meropenem)
• Other beta-lactam/beta-lactamase inhibitor combinations

ZOSYN's broad-spectrum activity, safety profile, and established clinical guidelines ensure steady hospital use, especially in the intensive care setting.

Patent Status and Regulatory Considerations

Patent Expiry and Generic Competition

The original patent for ZOSYN expired in 2014 in the U.S., leading to increased generic availability. This has resulted in significant downward pressure on prices, impacting gross margins. However, some formulations or delivery methods may retain market exclusivity until 2025-2028, depending on patent protections or brand extensions.

Regulatory Approvals and Off-Label Uses

ZOSYN has received approvals in multiple jurisdictions, with ongoing clinical trials for new indications such as ventilator-associated pneumonia and multidrug-resistant infections. These potential uses could strengthen future sales if approved.

Revenue and Cost Structure

Item	Details
Average Wholesale Price (AWP)	USD 100-150 per dose (varies by region and formulation)
Usage Volume	Approx. 10 million doses annually globally (estimate)
Gross Margins	Estimated at 35-45%, affected by generic competition
R&D Expenditure	Historically minimal; pipeline focus on new formulations

Patent expiry and generic competition accelerate price erosion, decreasing revenue per dose.

R&D and Pipeline Status

Limited pipeline investment exists due to the drug's age and patent expiration. Recent efforts focus on formulation improvements, such as extended infusion options, to differentiate from generics. No major new indications are under development that could substantially impact revenue.

External Factors Impacting Investment

Antimicrobial Resistance

Growing resistance to beta-lactam antibiotics could reduce the efficacy of ZOSYN. Multidrug-resistant organisms (e.g., ESBL-producing bacteria) may necessitate higher doses or alternative therapies, constraining usage growth.

Healthcare Policies and Stewardship

Antimicrobial stewardship programs aim to reduce broad-spectrum antibiotic use to combat resistance, affecting ZOSYN prescribing patterns. Regulatory policies promoting generic use also tend to lower prices.

Supply Chain and Manufacturing

Reliance on specific manufacturing facilities could pose risks if disruptions occur. Recent shortages of beta-lactam antibiotics highlight vulnerabilities needing assessment.

Risk Factors for Investment

• Declining revenues due to generic erosion post-patent expiry.
• Increased competition from newer antibiotics with broader activity or improved safety profiles.
• Resistance development diminishing clinical utility.
• Regulatory hurdles or policy changes restricting wholesale antibiotic use.

Investment Outlook Summary

ZOSYN's revenue stability faces headwinds from patent expirations and generic competition, compressing margins. Its entrenched position in hospital protocols provides some resilience but limits growth prospects. Strategic value may emerge from formulations that prolong or protect market exclusivity or from pipeline advancements addressing resistant infections.

Key Takeaways

• ZOSYN remains a core hospital antibiotic with significant market share pre-generic era.
• Patent expiries and generics have eroded pricing, compressing profit margins.
• Resistance trends and stewardship policies can limit future demand growth.
• Limited pipeline activity reduces long-term upside potential.
• Marginal opportunities exist in extended formulations or niche indications.

FAQs

Q1: How does patent expiration impact ZOSYN's market share?
Patent expiration enables generic manufacturing, increasing competition, lowering prices, and reducing brand-specific revenue.

Q2: Are there any approved next-generation formulations of ZOSYN?
Current efforts focus on infusion modifications; no significant new formulations are widely approved.

Q3: What is the potential impact of antimicrobial resistance on ZOSYN?
Rising resistance among certain bacteria can reduce ZOSYN's clinical efficacy, decreasing its usage.

Q4: How do hospital policies influence ZOSYN sales?
Stewardship programs aim to limit broad-spectrum antibiotic use, possibly reducing ZOSYN prescriptions.

Q5: What are alternative therapies replacing ZOSYN in resistant infections?
Carbapenems or newer agents such as ceftolozane/tazobactam are options, often with broader activity against resistant organisms.

---

References

[1] MarketWatch. (2022). Global antibiotics market size. Retrieved from https://www.marketwatch.com/press-release/global-antibiotics-market-size-trends-and-forecast-2022-2028-2022-01-01